Geert de Snoo

Netwerk

Over

My aim is to contribute to science-based conservation of biodiversity in human-dominated landscapes

Biografie

Geert de Snoo is director of the Netherlands Institute of Ecology of the Royal Netherlands Society of Arts & Sciences (NIOO-KNAW). He is also full professor of Conservation Biology at the Institute of Environmental Sciences (CML) of Leiden University.

His two main lines of research are:
- The effects of land use change on biodiversity and ecosystems. Here his focus is on nature conservation on farmland. How can we contribute to ecological recovery and transition to sustainable land use? Not only the impact of landscape elements, such as field margins, on biodiversity is examined, but also the socio-economic aspects are discussed.
- The impact of contaminants on biodiversity and ecosystems. More specifically, his focus is on the side effects of pesticides in both terrestrial and aquatic environments on invertebrates and vertebrates.
More recently, the conservation of large predators in human-dominated landscapes and the interaction between humans and wildlife have been added to his research portfolio.

Geert de Snoo studied biology at the Free University in Amsterdam and then became a researcher at the Centre of Environmental Sciences (CML) of Leiden University. During his PhD he investigated the potential of unsprayed field margins for enhancing environmental quality, promoting biodiversity and implications for agricultural practice. After his PhD, De Snoo acquired various grants from NWO, the EU, governments and the private sector. In 2003 De Snoo became a special professor in the field of nature conservation on farmland at Wageningen University. Since 2009 he is professor of Conservation Biology at Leiden University. So far, De Snoo has supervised about 35 PhD students.

Administrative positions:
Currently, De Snoo is member of the board of the Centre of Excellence for Netherlands Biodiversity Research. A combined research initiative of the Netherlands Institute of Ecology, Naturalis Biodiversity Center, the Royal Netherlands Institute for Sea Research and Westerdijk Fungal Biodiversity Institute. He is member of the Dutch Council on Animal Affairs, the independent council for multidisciplinary issues in the field of animal welfare and health for the Minister of Agriculture, Nature and Food Quality. He is also member of the Dutch Biology Council.

From 2012-2019 De Snoo has been Dean of the Faculty of Science of Leiden University. Between 2009 and 2012, he was Director of the Centre of Environmental Sciences (CML) at Leiden University. From 2016-2022 he was member/chair of the the supervisory Board of the Netherlands Centre for One Health (NCOH). For five years he was member of the Board for the Authorisation of Plant Protection Products and Biocides (Ctgb).

CV

Employment

  • 2019–Present
    Director Netherlands Institute of Ecology (NIOO-KNAW)
  • 2009–Present
    Professor Conservation Biology at the Institute of Environmental Sciences, Leiden University
  • 2012–2019
    Dean of the Faculty of Science, Leiden University
  • 2009–2012
    Director of the Institute of Environmental Sciences, Leiden University, and head of the Department of Conservation Biology
  • 2003–2012
    Professor, special chair Nature Conservation on Farmland, Wageningen University, Department of Nature Conservation and Plant Ecology
  • 2000–2008
    Associate professor and head of the Department of Environmental Biology of the Institute of Environmental Sciences, Leiden University
  • 1994–2000
    Assistant professor at of the Institute of Environmental Sciences, Leiden University, head of the Section Ecosystems and Environmental Quality
  • 1996–1997
    Postdoc NWO-STIMULANS-grant
  • 1990–1994
    Qualified researcher NWO, PhD project
  • 1986–1990
    Researcher at the Institute of Environmental Sciences at Leiden University

Education

  • 1990–1995
    PhD Environmental Science, Leiden University, Leiden
  • 1979–1986
    MSc Biology (Ecology / Ecotoxicology), Free University, Amsterdam

Nevenfuncties

Publicaties

Peer-reviewed publicaties

  • Evolutionary Applications
    19-03-2024

    Genetic diversity of lion populations in Kenya

    Mumbi Chege, Bobbie Sewalt, Francis Lesilau, Geert de Snoo, Bruce D. Patterson, Linus Kariuki, Moses Otiende, Patrick Omondi, Hans H. de Iongh, Klaas Vrieling, Laura D. Bertola
    The decline of lions (Panthera leo) in Kenya has raised conservation concerns about their overall population health and long-term survival. This study aimed to assess the genetic structure, differentiation and diversity of lion populations in the country, while considering the influence of past management practices. Using a lion-specific Single Nucleotide Polymorphism (SNP) panel, we genotyped 171 individuals from 12 populations representative of areas with permanent lion presence. Our results revealed a distinct genetic pattern with pronounced population structure, confirmed a north-south split and found no indication of inbreeding in any of the tested populations. Differentiation seems to be primarily driven by geographical barriers, human presence and climatic factors, but management practices may have also affected the observed patterns. Notably, the Tsavo population displayed evidence of admixture, perhaps attributable to its geographic location as a suture zone, vast size or past translocations, while the fenced populations of Lake Nakuru National Park and Solio Ranch exhibited reduced genetic diversity due to restricted natural dispersal. The Amboseli population had a high number of monomorphic loci likely reflecting a historical population decline. This illustrates that patterns of genetic diversity should be seen in the context of population histories and that future management decisions should take these insights into account. To address the conservation implications of our findings, we recommend prioritizing the maintenance of suitable habitats to facilitate population connectivity. Initiation of genetic restoration efforts and separately managing populations with unique evolutionary histories is crucial for preserving genetic diversity and promoting long-term population viability.
    https://doi.org/10.1111/eva.13676
  • Ecology and Evolution
    02-2024

    Effect of ecological and anthropogenic factors on grouping patterns in African lions across Kenya

    Mumbi Chege, Laura D. Bertola, Geert de Snoo, Shadrack Ngene, Tobias Otieno, Irene Amoke, Maarten van 't Zelfde, Stephanie Dolrenry, Femke Broekhuis, Will Tamis, Hans H. de Iongh, Nicholas B. Elliot
    Social carnivores frequently live in fission–fusion societies, where individuals that share a common territory or home range may be found alone, in subgroups, or altogether. Absolute group size and subgroup size is expected to vary according to resource distribution, but for species that are susceptible to anthropogenic pressures, other factors may be important drivers. African lions (Panthera leo) are the only truly social felid and lion prides are characterized by fission–fusion dynamics with social groups frequently splitting and reforming, and subgroup membership can change continuously and frequently. The number of individuals in a group can be reflective of social, ecological, and anthropogenic conditions. This dynamic behavior makes understanding lion grouping patterns crucial for tailoring conservation measures. The evolution of group living in lions has been the topic of numerous studies, and we drew on these to formulate hypotheses relating to group size and subgroup size variation. Based on data collected from 199 lion groups across eight sites in Kenya, we found that group sizes were smaller when lions were closer to human settlements, suggesting that edge effects are impacting lions at a national scale. Smaller groups were also more likely when they were far from water, and were associated with very low and very high levels of non-tree vegetation. We found significant differences between the study sites, with the Maasai Mara having the largest groups (mean ± SD = 7.7 ± 4.7, range = 1–19), and Amboseli conservation area the smallest (4.3 ± 3.5, range = 1–14). While long-term studies within a single site are well suited to thoroughly differentiate between absolute group size and subgroup size, our study provides unique insight into the correlates of grouping patterns in a vulnerable species at a national scale.
    https://doi.org/10.1002/ece3.10982
  • Ecological Indicators
    01-01-2024

    Well known indicator groups do not predict the decline of insects

    C.J.M. Musters, Hans Peter Honkoop, Geert de Snoo
    In decision making for insect conservation, one depends largely on knowledge of the relationship between changes in environmental factors and abundance of a very limited number of species. The species we have knowledge on cannot be regarded as a representative sample of all insects. How accurately do changes in the abundance of these species predict the changes in other species? To answer this question, we studied 373 insect species belonging to the Apidae (bees), Lepidoptera (butterflies), Orthoptera (grasshoppers), Ephemeroptera (mayflies), Trichoptera (caddisflies), Odonata (dragonflies), and Plecoptera (stoneflies), with known population trends and attributes in the Netherlands. The 78 attributes included morphological and demographic trait values, as well as habitat requirements of species. We trained Random Forests (RFs) with random samples and with taxonomic groups to predict the decline of the species based on their attributes. Then we used the trained RFs to predict the decline of the species outside the training groups and checked the accuracy of the predictions. The results showed that accuracy of the predictions of the RFs trained by the random samples increased from 0 to 0.20 (maximum 0.40, on a scale of 0 to 1) with sample size increasing from 10 to 90% of the insects. Moreover, we found that the accuracy of the predictions by the RFs trained with the taxonomic groups were zero in case of butterflies and grasshoppers, and low in other groups (maximum 0.37, in case of bees predicting terrestrial insects). Accuracy depended significantly on the size of the taxonomic group. Large over- or underestimation of number of declining species occurred in all cases. Further, we found that the taxonomic groups had few attributes important for predicting in common. The attribute ‘Active dispersion’ had the highest importance when all insects were used for training the RF. Using ‘indicator groups’ for predicting the decline of insects has a high risk of over- or underestimating the actual number of declining species and should therefore be advised against unless the indicator group is sure to be representative.
    https://doi.org/10.1016/j.ecolind.2023.111458
  • Agronomy for Sustainable Development
    27-11-2023

    People’s appreciation of colorful field margins in intensively used arable landscapes and the conservation of plants and invertebrates

    Geert de Snoo, Jacintha G.B. Van Dijk, W. Vletter, C.J.M. Musters
    Sown field margins can improve the conservation of biodiversity in rural areas and can contribute to the aesthetics of rural landscapes, thereby potentially increasing public support for agri-environmental measures. However, these two functions do not necessarily coincide. This raises the question whether field margins that are appreciated for their contribution to landscape aesthetics also deliver on the conservation of biodiversity. We conducted choice experiments with different groups of citizens and collected biodiversity data in the Netherlands, to investigate if the number of colors and vegetation cover in field margins increased respondents’ appreciation for them, and how these visual cues correlated with taxonomic diversity and abundance of plants and invertebrates in those field margins. Using manipulated photos, we also assessed whether the presence of colorful field margins in a range of different rural landscapes increased respondents’ appreciation of those landscapes. Respondents preferred colorful margins with high vegetation cover and showed a preference for green rural landscapes with colorful field margins. The presence of colorful field margins increased landscape aesthetics most in the least appreciated landscapes. The number of colors correlated positively with the diversity of sown and spontaneous plant species, and overall invertebrate abundance and abundance of predatory invertebrates, but was not related to invertebrate diversity. Our results show for the first time that colorful field margins support both public appreciation and diversity of plants and abundance of ground-dwelling invertebrates, with potential advantages to farmers in terms of natural pest control, at least in intensively used agricultural landscapes. However, management practices to maintain a high number of colors over time may be detrimental for invertebrate diversity. To optimize the different functions, we recommend that field margin layouts should consist of a perennial part that is allowed to develop over time, in combination with a part that is managed for its colorfulness.
    https://doi.org/10.1007/s13593-023-00933-5
  • Ecological Monographs
    01-02-2023

    Scientists' warning on climate change and insects

    Jeff A. Harvey, Kévin Tougeron, Rieta Gols, Robin Heinen, Mariana Abarca, Paul K. Abram, Yves Basset, Matty P. Berg, Carol Boggs, Jacques Brodeur, Pedro Cardoso, Jetske G. de Boer, Geert de Snoo, Charl Deacon, Jane E. Dell, Nicolas Desneux, Michael E. Dillon, Grant A. Duffy, Lee A. Dyer, Jacintha Ellers, Anahí Espíndola, James Fordyce, Matthew L. Forister, Caroline Fukushima, Matthew J. G. Gage, Carlos García‐Robledo, Claire Gely, Mauro Gobbi, Caspar A Hallmann, Thierry Hance, John Harte, Axel Hochkirch, Christian Hof, Ary A. Hoffmann, Joel G. Kingsolver, Greg P. A. Lamarre, William F Laurance, Blas Lavandero, Simon R Leather, Philipp Lehmann, Cécile Le Lann, Margarita M. López‐Uribe, Chun‐Sen Ma, Gang Ma, Joffrey Moiroux, Lucie Monticelli, Chris Nice, Paul J. Ode, Sylvain Pincebourde, William J. Ripple, Melissah Rowe, Michael J Samways, Arnaud Sentis, Alisha A. Shah, Nigel Stork, John S. Terblanche, Maddy Thakur, Matthew B. Thomas, Jason M. Tylianakis, Joan Van Baaren, Martijn van de Pol, Wim H. van der Putten, Hans Van Dyck, Wilco C. E. P. Verberk, David L Wagner, Wolfgang W. Weisser, William C. Wetzel, H. Arthur Woods, Kris A G Wyckhuys, Steven L Chown
    Climate warming is considered to be among the most serious of anthropogenicstresses to the environment, because it not only has direct effects on biodiver-sity, but it also exacerbates the harmful effects of other human-mediated threats. The associated consequences are potentially severe, particularly interms of threats to species preservation, as well as in the preservation of anarray of ecosystem services provided by biodiversity. Among the most affectedgroups of animals are insects—central components of many ecosystems—forwhich climate change has pervasive effects from individuals to communities.In this contribution to the scientists’warning series, we summarize the effectof the gradual global surface temperature increase on insects, in terms ofphysiology, behavior, phenology, distribution, and species interactions, as wellas the effect of increased frequency and duration of extreme events such as hotand cold spells, fires, droughts, and floods on these parameters. We warn that,if no action is taken to better understand and reduce the action of climatechange on insects, we will drastically reduce our ability to build a sustainablefuture based on healthy, functional ecosystems. We discuss perspectives onrelevant ways to conserve insects in the face of climate change, and we offerseveral key recommendations on management approaches that can beadopted, on policies that should be pursued, and on the involvement of thegeneral public in the protection effort.
    https://doi.org/10.1002/ecm.1553
  • Frontiers in Applied Mathematics and Statistics
    24-01-2023

    Enhancing the predictability of ecology in a changing world

    C.J.M. Musters, Don L. DeAngelis, Jeff A. Harvey, Wolf M. Mooij, Peter M. van Bodegom, Geert de Snoo
    Ecology is usually very good in making descriptive explanations of what is observed, but is often unable to make predictions of the response of ecosystems to change. This has implications in a human-dominated world where a suite of anthropogenic stresses are threatening the resilience and functioning of ecosystems that sustain mankind through a range of critical regulating and supporting services. In ecosystems, cause-and-effect relationships are difficult to elucidate because of complex networks of negative and positive feedbacks. Therefore, being able to effectively predict when and where ecosystems could pass into different (and potentially unstable) new states is vitally important under rapid global change. Here, we argue that such better predictions may be reached if we focus on organisms instead of species, because organisms are the principal biotic agents in ecosystems that react directly on changes in their environment. Several studies show that changes in ecosystems may be accurately described as the result of changes in organisms and their interactions. Organism-based theories are available that are simple and derived from first principles, but allow many predictions. Of these we discuss Trait-based Ecology, Agent Based Models, and Maximum Entropy Theory of Ecology and show that together they form a logical sequence of approaches that allow organism-based studies of ecological communities. Combining and extending them makes it possible to predict the spatiotemporal distribution of groups of organisms in terms of how metabolic energy is distributed over areas, time, and resources. We expect that this “Organism-based Ecology” (OE) ultimately will improve our ability to predict ecosystem dynamics.
    https://doi.org/10.3389/fams.2023.1046185
  • Landschap
    2023

    Landbouw en natuur:

    Geert de Snoo, Dik Melman
    We moeten meer rekening houden met natuur binnen het Nederlandse landbouwsysteem. De roep is actueler dan ooit, maar klinkt in feite al decennialang. Tegenwoordig kijken we daarbij vooral naar boeren en overheden en veel minder naar de machtige voedselketen. In dit artikel pleiten wij ervoor dat overheden hun rol oppakken én dat de keten verantwoordelijkheid neemt. Een organisatie à la de SER zou kunnen helpen helpen om stappen te maken.
  • Journal of Pollination Ecology
    2022

    The distributions of insect, wind and self pollination of plants in the Netherlands in relation to habitat types and 3D vegetation structure.

    Kaixuan Pan, Leon Marshall, Koos J.C. Biesmeijer, Geert de Snoo

    Plants can be pollinated in many ways, with insect, wind and selfing as the most common modes. While it seems likely that the occurrence of pollination modes is correlated with environmental conditions, e.g. vegetation structure, and this remains uncertain. Here, we mapped the composition of pollination modes of different plant groups (woody species, herbs, and grasses) across (semi-)natural habitats and their distributions in relation to 3D vegetation structure in the Netherlands. We found insect pollination is the most common mode across (semi-)natural habitats for woody species and herbs. Woody species pollinated by insects showed an even higher percentage in dune, river swamp and swamp peat than in other habitat types, whereas herbs showed a higher percentage of insect pollination in dune than in other habitat types. Grasses were always pollinated by wind or wind-self in all habitats. Woody plants pollinated by wind showed a positive relationship with canopy densities in three different strata from 2 to 20 m vegetation, while insect pollination showed a positive relationship with the canopy density of 0.5 to 2 m vegetation. All grass presented negative relationships with canopy density. Herbs showed different relationships with canopy densities of different strata dependent on pollination modes. Insect-pollinated species increased with canopy densities of low strata but decreased with canopy density of high strata, whereas wind-pollinated species decreased with canopy density of both low and high strata. We conclude that habitat and vegetation structure are important factors driving the distribution of pollination modes.

    https://doi.org/10.26786/1920-7603(2022)684
  • Ecological Indicators
    2022

    Distribution of ground-dwelling arthropods across landscapes with intensive agriculture in temperate areas

    C.J.M. Musters, J. M. R. Wiggers, Geert de Snoo
    The idea that land use in the surroundings may affect the abundance of arthropods on a location plays an important role in the argument that agriculture is the prime cause of the recently discovered general decline of insects. We studied the abundance of ground-dwelling arthropods in agricultural fields along a gradient of increasing distance from (semi)natural areas and in relation to landscape complexity in both the North America (Illinois, USA) and Europe (The Netherlands) using pitfalls. Our results showed that the total abundance did not change with distance when we controlled for vegetation height and landscape complexity around the sample locations. Vegetation height affected abundance positively in crop land and negatively in grassland. Landscape complexity only affected abundance when it was measured in a 6000 m radius around sample location, not at lower levels of scale. We conclude that an effect of increasing landscape complexity may be expected when that is done on a large enough scale.
    https://doi.org/10.1016/j.ecolind.2022.109042
  • PLoS One
    16-11-2021

    Importance of natural land cover for plant species’ conservation: A nationwide study in The Netherlands

    Kaixuan Pan, Merijn Moens, Leon Marshall, Ellen Cieraad, Geert de Snoo, Koos J.C. Biesmeijer
    While shifts to high-intensity land cover have caused overwhelming biodiversity loss, it remains unclear how important natural land cover is to the occurrence, and thus the conservation, of different species groups. We used over 4 million plant species’ observations to evaluate the conservation importance of natural land cover by its association with the occurrence probability of 1 122 native and 403 exotic plant species at 1 km resolution by species distribution models. We found that 74.9% of native species, 83.9% of the threatened species and 77.1% rare species preferred landscapes with over 50% natural land cover, while these landscapes only accounted for 15.6% of all grids. Most species preferred natural areas with a mixture of forest and open areas rather than areas with completely open or forested nature. Compared to native species, exotic species preferred areas with lower natural land cover and the cover of natural open area, but they both preferred extremely high and low cover of natural forest area. Threatened and rare species preferred higher natural land cover, either cover of natural forest area or cover of natural open area than not threatened and common species, but rare species were also more likely to occur in landscapes with 0–25% cover of natural open area. Although more natural land cover in a landscape will not automatically result in more native species, because there is often a non-linear increase in species occurrence probability when going from 0% to 100% natural land cover, for conserving purposes, over 80% natural land cover should be kept in landscapes for conserving threatened and very rare species, and 60% natural land cover is the best for conserving common native species. Our results stress the importance of natural areas for plant species’ conservation. It also informs improvements to species conservation by increasing habitat diversity.
    https://doi.org/10.1371/journal.pone.0259255
  • Proceedings of the National Academy of Sciences of the United States of America
    02-11-2021

    Experimental evidence for neonicotinoid driven decline in aquatic emerging insects

    S. Henrik Barmentlo, Maarten Schrama, Geert de Snoo, Peter M. van Bodegom, André van Nieuwenhuijzen, Martina G. Vijver

    There is an ongoing unprecedented loss in insects, both in terms of richness and biomass. The usage of pesticides, especially neonicotinoid insecticides, has been widely suggested to be a contributor to this decline. However, the risks of neonicotinoids to natural insect populations have remained largely unknown due to a lack of field-realistic experiments. Here, we used an outdoor experiment to determine effects of field-realistic concentrations of the commonly applied neonicotinoid thiacloprid on the emergence of naturally assembled aquatic insect populations. Following application, all major orders of emerging aquatic insects (Coleoptera, Diptera, Ephemeroptera, Odonata, and Trichoptera) declined strongly in both abundance and biomass. At the highest concentration (10 mg/L), emergence of most orders was nearly absent. Diversity of the most species-rich family, Chironomidae, decreased by 50% at more commonly observed concentrations (1 mg/L) and was generally reduced to a single species at the highest concentration. Our experimental findings thereby showcase a causal link of neonicotinoids and the ongoing insect decline. Given the urgency of the insect decline, our results highlight the need to reconsider the mass usage of neonicotinoids to preserve freshwater insects as well as the life and services depending on them.

    https://doi.org/10.1073/pnas.2105692118
  • Mammalia
    2021

    Spatial ecology of lions in a small, semi-fenced park surrounded by dense human populations

    Francis Lesilau, Stijn Verschueren, Maarten van't Zelfde, Kees C.J.M. Musters, Geert de Snoo, Hans H. de Iongh

    Human population growth near protected areas often results in detrimental edge effects for apex carnivores, such as the African lion. Urbanization leads to new scenarios of the human-lion conflict, thus understanding ranging patterns close to urban environments is crucial to inform future management strategies. We collected GPS data from 12 collared lions between 2014 and 2018 in Nairobi National Park, which borders the capital city of Kenya, Nairobi city. We estimated home ranges, calculated daily distance traveled and tested for differences between sex, season and pride. Additionally, we investigated how disturbance from Nairobi and surrounding human settlements affected space-use of lions, and tested for differences between sex, season and time of day. Lions showed restricted movements (4.5 km/day) and had small home ranges (49 km2). Male lions had larger ranges than females, but avoidance behavior of disturbed areas was similar. Lions took advantage during times of low human activity, i.e., during the night, to extend ranging behavior in search for resources. Risk for livestock depredation also increased during the wet season when lions roamed longer, more frequently, and deeper into the community lands. We recommend the establishment of buffer zones to maintain a viable lion population and reduced risk for conflict.

    https://doi.org/10.1515/mammalia-2020-0116
  • Ecological Indicators
    2021

    Distribution of flying insects across landscapes with intensive agriculture in temperate areas

    C.J.M. Musters, Tracy R. Evans, J. M. R. Wiggers, Maarten van't Zelfde, Geert de Snoo
    The abundance of insects has been strongly decreasing over the last decades, at least in the temperate zones of North America and Europe. This decrease has generally been attributed to increased human activity, especially increased agricultural production. Therefore, one would expect that insect abundance is spatially distributed according to human land use, more specifically that the abundance of insects in agricultural fields should be affected by the distance to (semi)natural areas. We tested this expectation on an extensive dataset of flying insects from Illinois, USA, and the Netherlands, Europe. Flying insects were collected with yellow sticky boards in agricultural fields at distances up to 566 m from (semi)natural areas. We did not find any effect of distance to (semi)natural area on the abundance of flying insects, after correcting for the confounding variables ‘landscape complexity’, ‘vegetation height’ and ‘plot locations’ (interior vs edge of the field). One might prematurely infer from this that (semi)natural areas do not affect flying insect abundance. We argue that knowing that flying insects are highly mobile, both active and passive, although sticky boards sample local insect abundance, abundance may be homogenized over a relatively large area in open landscapes. Therefore, the study of the effect of nature conservation management on flying insects should be done on spatially large scales, e.g., the landscape level.
    https://doi.org/10.1016/j.ecolind.2021.107889
  • Raffles Bulletin of Zoology
    2020

    Food preference of the bornean elephant (Elephas maximus borneensis) in North Kalimantan Province, Indonesia, and its conservation implications

    Rachmat B. Suba, Nils G.P. Beveridge, Wawan Kustiawan, Geert de Snoo, Hans H. de Iongh, Sip E. van Wieren, Young Hae Choi, Hye Kyong Kim

    The preference to feed on particular plant species may reflect the most desirable components that an animal perceives, in relation to what is available. The food preference of the Bornean elephant (Elephas maximus borneensis Deraniyagala, 1950) in the Sebuku area of North Kalimantan was studied by chemical analysis on the metabolites of several known food plant species. We analysed the chemical properties of the Bornean elephant diet from thirteen food-plant species which represented the level of food-plant categories utilised by the Bornean elephant in the study area. All samples were analysed for nutritional value, and their metabolic profiles were obtained using 1 H nuclear magnetic resonance spectroscopy. These data were subjected to multivariate data analyses to identify the common components. This study confirmed that Bornean elephants tend to follow a strategy to maximise their energy intake by selecting food items rich in sugar and crude protein and minimise fibrous elements. The fact that they also prefer food items with high glutamate suggests that taste plays a role and this element may be a cue for the Bornean elephant to assist in foraging and searching for palatable food.

    https://doi.org/10.26107/RBZ-2020-0090
  • Oryx
    2019

    Determining the risk of predator attacks around protected areas: the case of Bardia National Park, Nepal

    Subodh K. Upadhyaya, C.J.M. Musters, Babu Ram Lamichhane, Geert de Snoo, Maheshwar Dhakal, Hans H. de Iongh
    In this study we determined the probability of predator attacks on livestock around Bardia National Park, Nepal. We conducted semi-structured interviews to explore the patterns and factors affecting livestock losses in four administrative sectors of the Park's buffer zone. We developed models to investigate the overall probability of livestock loss, economic damage caused, and the respondents’ attitudes towards wildlife. The probability of leopard attacks on livestock was much higher (85% of all livestock lost to depredation) than that of tiger attacks (8%), and the northern sector experienced the highest loss of livestock (50% modelled probability of livestock loss) in the buffer zone. Livestock loss was significantly related to the number of livestock owned by respondents, their ethnic group, and village distance to the Park boundary. Economic damage was influenced by buffer zone sector, number of livestock owned, and distance to the Park boundary. Conservation attitudes depended on respondents’ knowledge of wildlife, levels of education and self-sufficiency, and the probability of livestock being killed by leopards. Respondents who were male, highly educated and self-sufficient were most likely to support conservation. Tigers are tolerated based on religious beliefs, and these cultural values, together with the sharing of conservation benefits, facilitate conservation. Leopards, however, are not tolerated in the same way and are the most damaging predators.
    https://doi.org/10.1017/S0030605318001436
  • Science of the Total Environment
    2019

    Neonicotinoids and fertilizers jointly structure naturally assembled freshwater macroinvertebrate communities

    S. Henrik Barmentlo, Maarten Schrama, Peter M. van Bodegom, Geert de Snoo, C.J.M. Musters, Martina G. Vijver
    Although it is widely acknowledged that a decline of freshwater biodiversity jeopardizes the functioning of freshwater ecosystems, the large number of (human-induced) pressures jointly acting on these systems hampers managing its biodiversity. To disentangle the magnitude and the temporal effects of these single and interacting pressures, experiments are required that study how these pressures affect the structuring of natural communities. We performed experiments with naturally assembled invertebrate communities in 36 experimental ditches to assess the single and joint effects of environmentally relevant concentrations of two commonly co-occurring stressors: fertilizer inputs and neonicotinoid insecticides, in this case thiacloprid. Specifically, we explored whether these agrochemicals result in sustained changes in community structure by inspecting divergence, convergence and short- /long-lived dissimilarity of communities, when compared to a control treatment. Our results indicate strong impacts on the abundance of different taxa by exposure to the agrochemicals. However, we found no effect of any treatment on total abundance, taxon richness or convergence/divergence (measured as beta dispersion) of the communities. Moreover, we found contrasting responses when both joint stressors were present: when considering abundance of different taxa, we observed that fertilizer additions reduced some of the thiacloprid toxicity. But when assessing the community structure, we found that exposure to both stressors consistently resulted in a more dissimilar community compared to the control. This dissimilarity was persistent up to four months after applying the agrochemicals, even though there was a turnover in taxa explaining this dissimilarity. This turnover indicates that the persistent dissimilarity can potentially be attributed to a rippling effect in the community rather than continued toxicity. Such shifts in natural freshwater invertebrate communities, months after the actual exposure, suggests that stressors may have important long-term repercussions for which may subsequently lead to changes in ecosystem functioning.
    https://doi.org/10.1016/j.scitotenv.2019.07.110
  • Tropical Conservation Science
    14-09-2018

    An Insight Into the Diet and Prey Preference of Tigers in Bardia National Park, Nepal

    Subodh K. Upadhyaya, C.J.M. Musters, Babu Ram Lamichhane, Geert de Snoo, Panna Thapa, Maheshwar Dhakal, Dibesh Karmacharya, Purna Man Shrestha, Hans H. de Iongh
    https://doi.org/10.1177/1940082918799476
  • PLoS One
    2018

    Effectiveness of a LED flashlight technique in reducing livestock depredation by lions (Panthera leo) around Nairobi National Park, Kenya

    Francis Lesilau, M. Fonck, M. Gatta, C. Musyoki, Maarten van't Zelfde, Gerard A. Persoon, Kees C.J.M. Musters, Geert de Snoo, Hans H. de Iongh
    The global lion (Panthera leo) population decline is partly a result of retaliatory killing in response to livestock depredation. Nairobi National Park (NNP) is a small protected area in Kenya surrounded by a human-dominated landscape. Communities around the park use flashlights to deter lions from their livestock bomas. We investigated the response by lions to the installation of a LED flashlight technique during 2007-2016. We interviewed 80 owners of livestock bomas with flashlights (n = 43) and without (n = 37) flashlights in the surroundings of NNP and verified reported attacks on bomas against predation data over10 years. The frequency of attacks on bomas equipped with flashlights was significantly lower compared to bomas without flashlights. We also found that after flashlight installation at livestock bomas, lion attacks took place further away from the park edge, towards areas where bomas without flashlights were still present. With increased numbers of flashlight installations at bomas in recent years, we further noticed a shift from nocturnal to more diurnal predation incidences. Our study shows that the LED flashlight technique is effective in reducing nocturnal livestock predation at bomas by lions. Long term studies on the effects as well as expansion of this technique into other communities around NNP are recommended.
    https://doi.org/10.1371/journal.pone.0190898
  • Environmental Toxicology and Chemistry
    2018

    Thiacloprid-induced toxicity influenced by nutrients: Evidence from in situ bioassays in experimental ditches

    S. Henrik Barmentlo, E. M. Parmentier, Geert de Snoo, Martina G. Vijver
    Many studies show that neonicotinoid insecticides cause toxicity to aquatic invertebrates. Some studies report that insecticide toxicity may differ in combination with other agrochemicals under realistic field conditions. To explore such altered toxicity further, we aimed to determine the single and combined effects of environmentally relevant levels of the neonicotinoid thiacloprid and nutrients on different endpoints of 4 aquatic invertebrate species. Animals were exposed to these agrochemicals using a caged experiment within experimental ditches. We observed thiacloprid-induced toxicity for 2 crustaceans, Daphnia magna and Asellus aquaticus, and for 1 out of 2 tested insect species, Cloeon dipterum. We observed no toxic effects for Chironomus riparius at the time-weighted average test concentration of 0.51g thiacloprid/L. For D. magna, the observed toxicity, expressed as the lowest-observed-effect concentration (LOEC), on growth and reproduction was present at thiacloprid concentrations that were 2456-fold lower than laboratory-derived LOEC values. This shows that these species, when exposed under natural conditions, may exhibit neonicotinoid-induced toxic stress. Contrary to the low nutrient treatment, such toxicity was often not observed under nutrient-enriched conditions. This was likely attributable to the increased primary production that allowed for compensatory feeding. These findings warrant the inclusion of different feeding regimes in laboratory experiments to retrieve the best estimates of neonicotinoid-induced toxicity in the natural environment. Environ Toxicol Chem 2018;37:1907-1915. (c) 2018 SETAC
    https://doi.org/10.1002/etc.4142
  • Science of the Total Environment
    2018

    Assessing combined impacts of agrochemicals: Aquatic macroinvertebrate population responses in outdoor mesocosms

    S. Henrik Barmentlo, Maarten Schrama, E. R. Hunting, R. Heutink, P.M. Van Bodegom, Geert de Snoo, Martina G. Vijver
    Agricultural ditches host a diverse community of species. These species often are unwarrantedly exposed to fertilizers and a wide-array of pesticides (hereafter: agrochemicals). Standardized ecotoxicological research provides valuable information to predict whether these pesticides possibly pose a threat to the organisms living within these ditches, in particular macro-invertebrates. However, knowledge on how mixtures of these agrochemicals affect macro-invertebrates under realistic abiotic conditions and with population and community complexity is mostly lacking. Therefore we examined here, using a full factorial design, the population responses of macroinvertebrate species assemblages exposed to environmentally relevant concentrations of three commonly used agrochemicals (for 35 days) in an outdoor experiment. The agrochemicals selected were an insecticide (imidacloprid), herbicide (terbuthylazine) and nutrients (NPK), all having a widespread usage and often detected together in watersheds. Effects on species abundance and body length caused by binary mixture combinations could be described from single substance exposure. However, when agrochemicals were applied as terDaly mixtures, as they are commonly found in agricultural waters, species' abundance often deviated from expectations made based on the three single treatments. This indicates that pesticide-mixture induced toxicity to population relevant endpoints are difficult to extrapolate to field conditions. As in agricultural ditches often a multitude (approx. up to 7) of agrochemicals residues are detected, we call other scientist to verify the ecological complexity of non-additive induced shifts in natural aquatic invertebrate populations and aquatic species assemblages. (C) 2018 Elsevier B.V. All rights reserved.
    https://doi.org/10.1016/j.scitotenv.2018.03.021
  • Journal of Exposure Science and Environmental Epidemiology
    2018

    Assessment of residential environmental exposure to pesticides from agricultural fields in the Netherlands

    Maartje Brouwer, H. Kromhout, Roel C.H. Vermeulen, J. Duyzer, Henk Kramer, G. Hazeu, Geert de Snoo, A. Huss
    We developed a spatio-temporal model for the Netherlands to estimate environmental exposure to individual agricultural pesticides at the residential address for application in a national case-control study on Parkinson's disease (PD). Data on agricultural land use and pesticide use were combined to estimate environmental exposure to pesticides for the period 1961 onwards. Distance categories of 0-50 m, > 50-100 m, > 100-500 m and > 500-1000 m around residences were considered. For illustration purposes, exposure was estimated for the control population (n = 607) in the PD case-control study. In a small validation effort, model estimates were compared with pesticide measurements in air and precipitation collected at 17 stations in 2000-2001. Estimated exposure prevalence was higher for pesticides used on commonly cultivated (rotating) crops than for pesticides used on fruit and bulbs only. Prevalence increased with increasing distance considered. Moderate-to-high correlations were observed between model estimates (<100-500 m and > 500-1000 m) and environmental pesticide concentrations measured in 2000-2001. Environmental exposure to individual pesticides can be estimated using relevant spatial and temporal data sets on agricultural land use and pesticide use. Our approach seems to result in accurate estimates of average environmental exposure, although it remains to be investigated to what extent this reflect personal exposure to agricultural pesticides.
    https://doi.org/10.1038/jes.2017.3
  • Tropical Ecology
    2018

    Does livestock predation reflect in negative local perceptions of Ethiopian wolves in South Wollo?

    G. Eshete, C. Sillero-Zubiri, Ellen Cieraad, C.J.M. Musters, Geert de Snoo, Hans H. de Iongh, J. Marino
    The conservation of rare and endangered carnivores in human dominated landscapes is particularly challenging when predators are perceived as a threat to livestock. This study verifies whether the human perception of Ethiopian wolves as predators of livestock accurately reflects the actual damage done by this specialist predator of highland rodents. With that purpose, we quantified the contributions of prey species, including livestock, to the diet of Ethiopian wolves by analysing 118 scats. We then compared them to the reported livestock losses and attitudes in 300 households surrounding wolf habitat in the highlands of South Wollo in north Ethiopia. We found 10 prey species, totalling 222 prey occurrences in the study sample. The most common prey were diurnal rodents, with 79.2% of all prey occurrences. Only 5.4% were livestock (sheep) remains, a result similar to that obtained in other wolf populations. The proportion of households reportedly affected by Ethiopian wolf predation was relatively low (17%), and these households lost an average of 1.0 sheep per year over the previous five years. Even though the proportion of households affected by livestock predation was relatively low, 88% of the households that reported losing sheep to Ethiopian wolves had a negative perception of the species, compared with only 9% of the households unaffected. Clearly current levels of livestock predation in South Wollo lead to widespread negative attitudes among the people affected, an emerging problem that requires the attention of conservationists and wildlife authorities.
  • The Great Lakes Entomologist
    2017

    Invertebrate Communities Associated with Three Early Phases of a Prairie Restoration Project

    Tracy R. Evans, M. J. Mahoney, E. D. Cashatt, B.W. Cross, Geert de Snoo, C.J.M. Musters
  • IOSR Journal of Engineering
    2017

    Evaluation of smallholder farming systems in the Western Highlands of Cameroon

    C. M. Tankou, Geert de Snoo, Gerard A. Persoon, Hans H. de Iongh
  • Tropical Conservation Science
    2017

    Rapid Expansion of Oil Palm Is Leading to Human-Elephant Conflicts in North Kalimantan Province of Indonesia

    Rachmat B. Suba, J. van der Ploeg, Maarten van't Zelfde, Y. W. Lau, T. F. Wissingh, Wawan Kustiawan, Geert de Snoo, Hans H. de Iongh
    Crop raiding by Bornean elephants (Elephas maximus borneensis) is increasing rapidly in North Kalimantan, mainly due to a rapid conversion of swiddens and secondary forest into oil palm plantations. In the Tulin Onsoi subdistrict, the area used by oil palm plantations has grown from 3,302.71 ha in 2001 to 21,124.93 ha in 2014. Particularly from 2006 to 2010, the area covered by oil palm plantations increased rapidly (418%). Preventing further encroachment of oil palm plantations in elephant habitat and regulating land use change are keys to stop further population declines and make way for the reestablishment of a viable elephant population in Kalimantan. Crop raiding is a strong determinant of the local people's perceptions of elephants and risks eroding cultural values that enabled people to coexist with elephants. People's perception and attitude toward elephants are generally negative. Nevertheless, negative attitudes have not led to cases of retaliation in the Tulin Onsoi subdistrict. Public education at the community level could strengthen cultural values and foster coexistence between humans and elephants.
    https://doi.org/10.1177/1940082917703508
  • Journal of Industrial Ecology
    2017

    No Matter - How? Dealing with Matter-less Stressors in LCA of Wind Energy Systems

    S. Cucurachi, C. C. van der Giesen, R. Heijungs, Geert de Snoo
    The portfolio of impacts that are quantified in life cycle assessment (LCA) has grown to include rather different stressors than those that were the focus of early LCAs. Some of the newest life cycle impact assessment (LCIA) models are still in an early phase of development and have not yet been included in any LCA study. This is the case for sound emissions and noise impacts, which have been only recently modeled. Sound emissions are matter-less, time dependent, and bound to the physical properties of waves. The way sound emissions and the relative noise impacts are modeled in LCA can show how new or existing matterless impacts can be addressed. In this study, we analyze, through the example of sound emissions, the specific features of a matter-less impact that does not stem from the use of a kilogram of matter, nor is related to the emission of a kilogram of matter. We take as a case study the production of energy by means of wind turbines, contradicting the commonly held assumption that windmills have no emissions during use. We show how to account for sound emissions in the life cycle inventory phase of the life cycle of a wind turbine and then calculate the relative impacts using a noise LCIA model.
    https://doi.org/10.1111/jiec.12416
  • International Journal of Agricultural Sustainability
    2017

    Promoting nature conservation by Dutch farmers: a governance perspective

    H. A. C. Runhaar, Th. C.P. Melman, F. G. Boonstra, J. W. Erisman, L. G. Horlings, Geert de Snoo, Cjam Termeer, M.J. Wassen, J. Westerink, B. J. M. Arts
    Reconciling productive agricultural practices with nature conservation is not only an ecological challenge, but also a demanding matter of governance. This paper analyses the potential as well as the limitations of various governance arrangements, and explores ways to enhance the governance of nature conservation in agricultural landscapes. We assume four conditions to contribute to the performance of these arrangements: farmers should be motivated, demanded, enabled, and legitimized to participate in arrangements that promote nature conservation by farmers. We analyse 10 distinct Dutch governance arrangements in the period 2000-2016, including agri-environment schemes but also privately initiated arrangements. The arrangements target a large but unknown share of farmers and farmlands, but nature conservation ambition levels are generally low to moderate. The expected low-to-moderate performance is associated with a low-to-moderate motivation, demand, and ability. Underlying are stronger forces driving towards intensification and problems farmers face in recuperating the cost of nature conservation. New greening requirements in the EU Common Agricultural Policy and in agri-food supply chains are first, cautious steps addressing these fundamental drivers of ecological degradation. More ambitious greening requirements may contribute to a higher motivation and ability of larger groups of farmers to implement nature conservation measures.
    https://doi.org/10.1080/14735903.2016.1232015
  • Environment International
    2017

    Environmental exposure to pesticides and the risk of Parkinson's disease in the Netherlands

    Maartje Brouwer, A. Huss, Marianne van der Mark, P. C. G. Nijssen, W. M. Mulleners, A. M. G. Sas, T. van Laar, Geert de Snoo, H. Kromhout, Roel C.H. Vermeulen
    Background: Exposure to pesticides has been linked to Parkinson's disease (PD), although associations between specific pesticides and PD have not been well studied. Residents of rural areas can be exposed through environmental drift and volatilization of agricultural pesticides. Objectives: Our aim was to investigate the association between lifetime environmental exposure to individual pesticides and the risk of PD, in a national case-control study. Methods: Environmental exposure to pesticides was estimated using a spatio-temporal model, based on agricultural crops around the residential address. Distance up to 100 m from the residence was considered most relevant, considering pesticide drift potential of application methods used in the Netherlands. Exposure estimates were generated for 157 pesticides, used during the study period, of which four (i.e. paraquat, maneb, lindane, benomyl) were considered a priori relevant for PD. Results: A total of 352 PD cases and 607 hospital-based controls were included. No significant associations with PD were found for the a priori pesticides. In a hypothesis generating analysis, including 153 pesticides, increased risk of PD was found for 21 pesticides, mainly used on cereals and potatoes. Results were suggestive for an association between bulb cultivation and PD. Conclusions: For paraquat, risk estimates for the highest cumulative exposure tertile were in line with previously reported elevated risks. Increased risk of PD was observed for exposure to (a cluster of) pesticides used on rotating crops. High correlations limited our ability to identify individual pesticides responsible for this association. This study provides some evidence for an association between environmental exposure to specific pesticides and the risk of PD, and generates new leads for further epidemiological and mechanistic research.
    https://doi.org/10.1016/j.envint.2017.07.001
  • Journal for Nature Conservation
    2016

    The loss of biodiversity conservation in EU research programmes: Thematic shifts in biodiversity wording in the environment themes of EU research programmes FP7 and Horizon 2020

    J. F. Admiraal, C.J.M. Musters, Geert de Snoo
    Society has been seeking ways to express biodiversity's value to stimulate its protection. Economic valuation of ecosystem services has had limited success to motivate biodiversity protection and reaching the EU 2020 biodiversity strategy targets is in danger of failure. The expression of biodiversity's value in policy documents thus becomes a topic of discussion, because it greatly influences the ways policy makers think about environmental problems. We present an analysis of the word use related to biodiversity conservation versus ecosystem services in the environment themes of the FP7 and Horizon 2020 research work programs of the European Commission in the period of 2007-2014, and the projects accepted under these themes. We conclude first that biodiversity was lost as a topic in the transition from FP7 to Horizon 2020, accompanied by a three-quarters loss of biodiversity topics in the projects accepted under these research work programs. Moreover, the use of 'ecosystem services' was 1.5 times higher at the end of that period compared to the beginning in the research work programs, to the detriment of the use of 'sustainability' and 'conservation' which halved during that same period. In the light of international commitments to biodiversity conservation, the focus toward ecosystem services and away from conservation is of great concern. (C) 2015 Elsevier GmbH. All rights reserved.
    https://doi.org/10.1016/j.jnc.2015.12.008
  • Journal for Nature Conservation
    2016

    Effects of grass field margin management on food availability for Black-tailed Godwit chicks

    J. M. R. Wiggers, Jasper van Ruijven, Frank Berendse, Geert de Snoo
    Over the last six decades, populations of wader species like the Black-tailed Godwit (Limosa limosa) have sharply decreased in the Netherlands. Agricultural intensification has led to reduced habitat quality for meadow birds. As a consequence, reproductive success has declined. One of the main drivers of this decline in reproductive success is reduced food availability for meadow bird chicks. Agri-environment schemes (AES), designed to halt this decline, have so far been insufficient. Most of these AES focus on entire fields, but recent research suggests that differences in suitability exist within fields. Grass field margins may be more suitable for meadow bird chicks than the center of intensively managed grass lands. To improve existing meadow bird AES it could be beneficial to implement additional management in field margins of intensively managed grass fields. An already existing type of field margin AES with additional management is the botanical field margin. Here, we evaluate four different types of field margin management, including botanical field margins, focusing on aerial insects (an important part of the diet of Black-tailed Godwit chicks and Redshank chicks) in field centers and margins. Grass field margins contained more large aerial insects than field centers and, more importantly, additional management of the grass field margin increased the number of aerial insects in the margin. We conclude that combining meadow bird AES and botanical field margin management may enhance meadow bird food availability and improve the efficacy of AES. (C) 2015 Elsevier GmbH. All rights reserved.
    https://doi.org/10.1016/j.jnc.2015.11.001
  • Journal for Nature Conservation
    2016

    Landscape complexity and farmland biodiversity: Evaluating the CAP target on natural elements

    A. Cormont, Henk Siepel, J. Clement, Th. C.P. Melman, Michiel F. WallisDeVries, Chris A.M. Van Turnhout, L. B. Sparrius, M. Reemer, Koos J.C. Biesmeijer, Frank Berendse, Geert de Snoo
    Increasing pressures on natural areas and limited conservation budgets require, particularly in rural landscapes in the Western world, an immediate answer to the question how much natural area is required to provide a sustainable future for wild plant and animal species on farmland. The European Union proposed in its Common Agricultural Policy that 3-7% of EU farmland should be managed as ecological focus area (EFA) in order to halt biodiversity loss. For the first time, we empirically assessed the implications of this policy by evaluating the effects of the density of natural elements in agricultural landscapes on multi-taxon species richness, including vascular plants, breeding birds, butterflies, hoverflies, dragonflies, and grasshoppers for an entire European country. We found that species richness increased either as linear or as a logarithmic function of the proportion of natural elements in the landscape, but not with a sigmoid function as predicted by the 'intermediate landscape complexity' hypothesis. Even landscapes with 3-7% of natural elements harboured generally 37-75% of maximum species richness, indicating good potential of implementing the CAP target to preserve farmland biodiversity. However, differences between the 3 and 7% limits were considerable for butterflies, birds, and hoverflies. Also, the shape of the species richness response was shown to differ between landscape types for butterflies. Thus, it may be necessary to develop tailor-made guidelines at regional levels. (C) 2015 Elsevier GmbH. All rights reserved.
    https://doi.org/10.1016/j.jnc.2015.12.006
  • Land
    2016

    Enhancement of Linear Agricultural Areas to Provide Invertebrates as Potential Food for Breeding Birds

    Tracy R. Evans, M. J. Mahoney, E. D. Cashatt, Geert de Snoo, C.J.M. Musters
    Birds are an important part of the agricultural landscape, as having nature value, but also as pest control agents and bio-indicators for the health of the environment. Here we look at linear non-crop elements in agricultural areas as a potential source of food for nestlings of avian species. We measured invertebrate availability as it relates to structural complexity at the local and landscape levels in three counties in central Illinois. Invertebrates were measured with taxonomic diversity, abundance, and estimated biomass during spring of 2012 and 2013. Our study shows that easily modifiable field edge characteristics have the greatest impact on invertebrate diversity and abundance, as compared to field and landscape features. This finding shows that a potential invertebrate food source as measured by both diversity and biomass, may be easily enhanced without changes to agricultural practices.
    https://doi.org/10.3390/land5030026
  • Land Use Policy
    2016

    Factors underlying farmers' intentions to perform unsubsidised agri-environmental measures

    W. F. A. van Dijk, A. M. Lokhorst, Frank Berendse, Geert de Snoo
    Over the last decades there is a growing body of literature on how to enhance farmers' participation in voluntary subsidised agri-environmental programmes. However, additional unsubsidised agri-environmental measures that farmers perform are often ignored. The willingness to perform these measures may give a better insight into farmers' motivation for agri-environmental measures than subsidised measures because it likely depends only on farmers' intrinsic motivation and not on extrinsic factors such as a financial compensation. In this study we used an extended version of the Theory of Planned Behaviour (TPB) to investigate which factors are associated with farmers' intention to perform unsubsidised agri-environmental measures. Our results demonstrate that attitude, perceived social norms and perceived personal ability are significantly associated with farmers' intention to perform these measures. However, self-identity is the most dominant predictor of farmers' intentions. Furthermore we found that Environmental Cooperatives (ECs) positively influence farmers' willingness to perform additional unsubsidised measures by means of facilitation and group pressure. We conclude that in order to increase farmers' willingness to perform agri-environmental measures, self-identity should be addressed by means of e.g. benchmarking instruments in combination with commitment making or labelling of environmental friendly identities. Also, ECs are more important for unsubsidised measures than previously assumed - we recommended that they change their focus to include unsubsidised as well as subsidised conservation. (C) 2016 Elsevier Ltd. All rights reserved.
    https://doi.org/10.1016/j.landusepol.2016.09.003
  • Insects
    2016

    The Impact of Landscape Complexity on Invertebrate Diversity in Edges and Fields in an Agricultural Area

    Tracy R. Evans, M. J. Mahoney, E. D. Cashatt, J. Noordijk, Geert de Snoo, C.J.M. Musters
    Invertebrate diversity is important for a multitude of ecosystem services and as a component of the larger ecological food web. A better understanding of the factors influencing invertebrate taxonomic richness and diversity at both local and landscape scales is important for conserving biodiversity within the agricultural landscape. The aim of this study was to determine if invertebrate richness and diversity in agricultural field interiors and edges in central Illinois, USA, were related to the complexity of the surrounding landscape. Our results show taxonomic richness and diversity in field edges is positively related to large scale landscape complexity, but the relationship is negative for field interiors. These unexpected results need further study.
    https://doi.org/10.3390/insects7010007
  • PLoS One
    2015

    Autosomal and mtDNA Markers Affirm the Distinctiveness of Lions in West and Central Africa

    Laura D. Bertola, L. Tensen, P. Van Hooft, P. A. White, C. A. Driscoll, Philipp Henschel, A. Caragiulo, I. Dias-Freedman, E. A. Sogbohossou, P. N. Tumenta, T. H. Jirmo, Geert de Snoo, Hans H. de Iongh, Klaas Vrieling
    The evolutionary history of a species is key for understanding the taxonomy and for the design of effective management strategies for species conservation. The knowledge about the phylogenetic position of the lion (Panthera leo) in West/Central Africa is largely based on mitochondrial markers. Previous studies using mtDNA only have shown this region to hold a distinct evolutionary lineage. In addition, anthropogenic factors have led to a strong decline in West/Central African lion numbers, thus, the conservation value of these populations is particularly high. Here, we investigate whether autosomal markers are concordant with previously described phylogeographic patterns, and confirm the unique position of the West/Central African lion. Analysis of 20 microsatellites and 1,454 bp of the mitochondrial DNA in 16 lion populations representing the entire geographic range of the species found congruence in both types of markers, identifying four clusters: 1) West/Central Africa, 2) East Africa, 3) Southern Africa and 4) India. This is not in line with the current taxonomy, as defined by the IUCN, which only recognizes an African and an Asiatic subspecies. There are no indications that genetic diversity in West/Central Africa lions is lower than in either East or Southern Africa, however, given this genetic distinction and the recent declines of lion numbers in this region, we strongly recommend prioritization of conservation projects in West/Central Africa. As the current taxonomic nomenclature does not reflect the evolutionary history of the lion, we suggest that a taxonomic revision of the lion is warranted.
    https://doi.org/10.1371/journal.pone.0137975
  • Journal of Ornithology
    2015

    Effects of breeding habitat and field margins on the reproductive performance of Skylarks (Alauda arvensis) on intensive farmland

    M. W. Kuiper, H. J. Ottens, Jasper van Ruijven, B. J. Koks, Geert de Snoo, Frank Berendse
    Field margin management is a common measure employed in Europe to support farmland bird populations. In this study we found and analysed 237 nests of the Skylark Alauda arvensis in the Netherlands over a period of 6 years to determine the effects of arable field margins and breeding crop on nest-level reproductive success. Additionally, the effect of field margins on predation was investigated and food availability in crops and field margins was compared. Neither clutch size, nest survival nor nestling body weight were improved by field margin availability, irrespective of the breeding crop used. However, the choice of breeding crop had important effects. Nestling weight was significantly lower in cereals than in grassland and lucerne, corresponding with the low prey densities present in cereals. Nest survival was lowest in grassland due to frequent silage cutting. Predation rates were highest in cereals but were not affected by field margin proximity. The highest reproductive success was achieved in lucerne, which was mown twice a year and retained a suitable height for breeding throughout the breeding season. We conclude that field margins are not sufficient to maintain a Skylark population in this intensively farmed area. The presumably more subtle effects of increased food availability cannot compensate for the high nest failure rates resulting from agricultural operations and predation. In this and similar areas, the provisioning of safe nesting habitat throughout the breeding season is essential to improve breeding performance. Our research suggests that this can be achieved by reducing the frequency of silage cutting on grassland and by increasing the surface area of lucerne.
    https://doi.org/10.1007/s10336-015-1159-8
  • Environmental Toxicology and Chemistry
    2015

    Assessing toxicity of copper nanoparticles across five cladoceran species

    L. Song, Martina G. Vijver, Geert de Snoo, Wjgm Peijnenburg
    As a result of ever increasing applications, nanoparticles will eventually end up in the environment. However, currently no common principle has been established to help understand the toxicity of nanoparticles (NPs) across species. Therefore, it is difficult to estimate the potential risks of nanoparticles to untested species in the environment. The authors exposed 4 different sizes of copper nanoparticles (CuNPs) and 1 submicron-sized copper particle to 5 cladoceran species (Daphnia magna, Daphnia pulex, Daphnia galeata, Ceriodaphnia dubia, and Chydorus sphaericus) to investigate whether morphological attributes of species can help to assess the acute toxicity of CuNPs across species. The results showed that rod-shaped CuNPs caused much lower toxicity to all species than spherical CuNPs. Both the particles and ions contributed to the total toxicity of the CuNP suspensions. Moreover, the toxicity caused by particles in 5 different copper suspensions increases with decreasing body length, surface area, and body volume of neonates of 5 cladoceran species. Especially the correlations between body volume of the 5 cladoceran species tested and the corresponding toxicity caused by 5 different CuNPs were statistically significant, and in all cases r(adj)(2) was higher than 0.51 (p <0.001). The highest correlation was found between body volume and the toxicity of the 78-nm CuNPs (r(adj)(2)=0.95, p <0.001). To conclude, the correlations between attributes of cladoceran species and the toxicity of CuNPs reported in the present study evoke the possibility to assess and extrapolate the toxicity of nanoparticles across species with similar attributes. Environ Toxicol Chem 2015;34:1863-1869. (c) 2015 SETAC
    https://doi.org/10.1002/etc.3000
  • Environmental Science and Technology
    2015

    Comparison of Asian Aquaculture Products by Use of Statistically Supported Life Cycle Assessment

    P. J. G. Henriksson, A. Rico, Wenbo Zhang, S. Ahmad-Al-Nahid, Ryan J Newton, L. T. Phan, Zongfeng Zhang, J. Jaithiang, H. M. Dao, T. M. Phu, D. C. Little, F. J. Murray, K. Satapornvanit, Liping Liu, Qigen Liu, Md. Mozammel Haque, F. Kruijssen, Geert de Snoo, R. Heijungs, P.M. Van Bodegom, J. B. Guinee
    We investigated aquaculture production of Asian tiger shrimp, whiteleg shrimp, giant river prawn, tilapia, and pangasius catfish in Bangladesh, China, Thailand, and Vietnam by using life cycle assessments (LCAs), with the purpose of evaluating the comparative eco-efficiency of producing different aquatic food products. Our starting hypothesis was that different production systems are associated with significantly different environmental impacts, as the production of these aquatic species differs in intensity and management practices. In order to test this hypothesis, we estimated each system's global warming, eutrophication, and freshwater ecotoxicity impacts. The contribution to these impacts and the overall dispersions relative to results were propagated by Monte Carlo simulations and dependent sampling. Paired testing showed significant (p <0.05) differences between the median impacts of most production systems in the intraspecies comparisons, even after a Bonferroni correction. For the full distributions instead of only the median, only for Asian tiger shrimp did more than 95% of the propagated Monte Carlo results favor certain farming systems. The major environmental hot-spots driving the differences in environmental performance among systems were fishmeal from mixed fisheries for global warming, pond runoff and sediment discards for eutrophication, and agricultural pesticides, metals, benzalkonium chloride, and other chlorine-releasing compounds for freshwater ecotoxicity. The Asian aquaculture industry should therefore strive toward farming systems relying upon pelleted species-specific feeds, where the fishmeal inclusion is limited and sourced sustainably. Also, excessive nutrients should be recycled in integrated organic agriculture together with efficient aeration solutions powered by renewable energy sources.
    https://doi.org/10.1021/acs.est.5b04634
  • Land Use Policy
    2015

    Collective agri-environment schemes: How can regional environmental cooperatives enhance farmers' intentions for agri-environment schemes?

    W. F. A. van Dijk, A. M. Lokhorst, Frank Berendse, Geert de Snoo
    The effectiveness of agri-environment schemes (AES) in enhancing biodiversity on farmland and creating a long-lasting change in farmers' motivation towards a more environmental-friendly practice is still strongly debated. Applying a regional approach has been advocated widely to make AES more ecologically and socially sustainable. In the Netherlands, some AES are performed collectively by large regional groups of farmers called Environmental Cooperatives (EC). We hypothesise that these cooperatives enhance farmers' intention to participate by facilitating the application of AES, but also by generating group pressure. In the study at hand, we used an extended version of the Theory of Planned Behaviour (TPB) to investigate which factors are associated with farmers' intention to participate in two kinds of collective AES (ditch bank management and the protection of meadow birds). Our results demonstrate that attitude and perceived personal ability to participate in these AES are associated with the intention of farmers to participate in ditch bank management. However, for the protection of meadow birds, social pressure, self-identity and facilitation by the EC also relate to the intention of farmers. We conclude that the facilitation undertaken by ECs positively relates to farmers' intention to participate in collective AES. (C) 2014 Elsevier Ltd. All rights reserved.
    https://doi.org/10.1016/j.landusepol.2014.10.005
  • PLoS One
    2015

    Product Carbon Footprints and Their Uncertainties in Comparative Decision Contexts

    P. J. G. Henriksson, R. Heijungs, H. M. Dao, L. T. Phan, Geert de Snoo, J. B. Guinee
    In response to growing awareness of climate change, requests to establish product carbon footprints have been increasing. Product carbon footprints are life cycle assessments restricted to just one impact category, global warming. Product carbon footprint studies generate life cycle inventory results, listing the environmental emissions of greenhouse gases from a product's lifecycle, and characterize these by their global warming potentials, producing product carbon footprints that are commonly communicated as point values. In the present research we show that the uncertainties surrounding these point values necessitate more sophisticated ways of communicating product carbon footprints, using different sizes of catfish (Pangasius spp.) farms in Vietnam as a case study. As most product carbon footprint studies only have a comparative meaning, we used dependent sampling to produce relative results in order to increase the power for identifying environmentally superior products. We therefore argue that product carbon footprints, supported by quantitative uncertainty estimates, should be used to test hypotheses, rather than to provide point value estimates or plain confidence intervals of products' environmental performance.
    https://doi.org/10.1371/journal.pone.0121221
  • Sustainability
    2015

    The Environmental Sustainability of Nations: Benchmarking the Carbon, Water and Land Footprints against Allocated Planetary Boundaries

    K. Fang, R. Heijungs, Z. Duan, Geert de Snoo
    Growing scientific evidence for the indispensable role of environmental sustainability in sustainable development calls for appropriate frameworks and indicators for environmental sustainability assessment (ESA). In this paper, we operationalize and update the footprint-boundary ESA framework, with a particular focus on its methodological and application extensions to the national level. By using the latest datasets available, the planetary boundaries for carbon emissions, water use and land use are allocated to 28 selected countries in comparison to the corresponding environmental footprints. The environmental sustainability ratio (ESR)an internationally comparable indicator representing the sustainability gap between contemporary anthropogenic interference and critical capacity thresholdsallows one to map the reserve or transgression of the nation-specific environmental boundaries. While the geographical distribution of the three ESRs varies across nations, in general, the worldwide unsustainability of carbon emissions is largely driven by economic development, while resource endowments play a more central role in explaining national performance on water and land use. The main value added of this paper is to provide concrete evidence of the usefulness of the proposed framework in allocating overall responsibility for environmental sustainability to sub-global scales and in informing policy makers about the need to prevent the planet's environment from tipping into an undesirable state.
    https://doi.org/10.3390/su70811285
  • Ecological Economics
    2015

    Understanding the complementary linkages between environmental footprints and planetary boundaries in a footprint-boundary environmental sustainability assessment framework

    K. Fang, R. Heijungs, Geert de Snoo
    While in recent years both environmental footprints and planetary boundaries have gained tremendous popularity throughout the ecological and environmental sciences, their relationship remains largely unexplored. By investigating the roots and developments of environmental footprints and planetary boundaries, this paper challenges the isolation of the two research fields and provides novel insights into the complementary use of them. Our analysis demonstrates that knowledge of planetary boundaries improves the policy relevance of environmental footprints by providing a set of consensus-based estimates of the regenerative and absorptive capacity at the global scale and, in reverse, that the planetary boundaries framework benefits from well-grounded footprint models which allow for more accurate and reliable estimates of human pressure on the planet's environment A framework for integration of environmental footprints and planetary boundaries is thus proposed. The so-called footprint-boundary environmental sustainability assessment framework lays the foundation for evolving environmental impact assessment to environmental sustainability assessment aimed at measuring the sustainability gap between current magnitudes of human activities and associated capacity thresholds. As a first attempt to take advantage of environmental footprints and planetary boundaries in a complementary way, there remain many gaps in our knowledge. We have therefore formulated a research agenda for further scientific discussions, mainly including the development of measurable boundaries in relation to footprints at multiple scales and their trade-offs, and the harmonization of the footprint and boundary metrics in terms of environmental coverage and methodological choices. All these points raised, in our view, will play an important role in setting practical and tangible policy targets for adaptation and mitigation of worldwide environmental unsustainability. (c) 2015 Elsevier B.V. All rights reserved.
    https://doi.org/10.1016/j.ecolecon.2015.04.008
  • Ardea
    2015

    Food availability for meadow bird families in grass field margins

    J. M. R. Wiggers, Jasper van Ruijven, A. P. Schaffers, Frank Berendse, Geert de Snoo
    Agricultural intensification in grasslands has led to the decline of meadow bird populations in The Netherlands in the last 60 years. Habitat for meadow bird chicks has declined in quality and quantity, thereby reducing food availability. Agri-environment schemes (AES) to halt the decline in meadow bird numbers have thus far been insufficient. These AES are on the level of entire fields, but recent research suggests that margins of fields may be more suitable chick habitat than centres of fields. Therefore, it could be productive to specifically target grass field margins as part of meadow bird AES. Our study examined the differences in food availability for meadow bird families in different portions of a grass field. Invertebrates were sampled in different locations on the field and results were compared to known dietary preferences of four species of meadow bird chicks. We show strong differences in food availability within fields, depending on meadow bird species. The preferred prey species of chicks of Black-tailed Godwit Limosa limosa and Redshank Tringa totanus predominantly occurred in field margins, whereas those of Oystercatcher Haematopus ostralegus chicks were found mostly in the main part of the field. The prey species of Northern Lapwing Vanellus vanellus chicks showed no clear pattern within fields. We conclude that food availability within a field differs spatially between meadow bird species. Particularly for Black-tailed Godwit and Redshank, grass field margins constitute an important part of the field. Therefore, specific management to further enhance food availability in these margins may constitute an important addition to the existing mosaic approach.
    https://doi.org/10.5253/arde.v103i1.a2
  • Electromagnetic Biology and Medicine
    2014

    Investigating short-term exposure to electromagnetic fields on reproductive capacity of invertebrates in the field situation

    Martina G. Vijver, J. F. B. Bolte, Tracy R. Evans, Will Tamis, Wjgm Peijnenburg, C.J.M. Musters, Geert de Snoo
    Organisms are exposed to electromagnetic fields from the introduction of wireless networks that send information all over the world. In this study we examined the impact of exposure to the fields from mobile phone base stations (GSM 900 MHz) on the reproductive capacity of small, virgin, invertebrates. A field experiment was performed exposing four different invertebrate species at different distances from a radiofrequency electromagnetic fields (RF EMF) transmitter for a 48-h period. The control groups were isolated from EMF exposure by use of Faraday cages. The response variables as measured in the laboratory were fecundity and number of offspring. Results showed that distance was not an adequate proxy to explain dose-response regressions. No significant impact of the exposure matrices, measures of central tendency and temporal variability of EMF, on reproductive endpoints was found. Finding no impact on reproductive capacity does not fully exclude the existence of EMF impact, since mechanistically models hypothesizing non-thermal-induced biological effects from RF exposure are still to be developed. The exposure to RF EMF is ubiquitous and is still increasing rapidly over large areas. We plea for more attention toward the possible impacts of EMF on biodiversity.
    https://doi.org/10.3109/15368378.2013.783846
  • Nanotoxicology
    2014

    Species-specific toxicity of copper nanoparticles among mammalian and piscine cell lines

    L. Song, M. Connolly, M. L. Fernandez-Cruz, Martina G. Vijver, Marta Fernández, E. Conde, Geert de Snoo, Wjgm Peijnenburg, J. M. Navas
    The four copper nanoparticles (CuNPs) with the size of 25, 50, 78 and 100 nm and one type of micron-sized particles (MPs) (similar to 500 nm) were exposed to two mammalian (H4IIE and HepG2) and two piscine (PLHC-1 and RTH-149) cell lines to test the species-specific toxicities of CuNPs. The results showed that the morphologies, ion release and size of the particles all played an important role when investigating the toxicity. Furthermore, the authors found that the particle forms of CuNPs in suspensions highly contribute to the toxicity in all exposed cell lines whereas copper ions (Cu2+) only caused significant responses in mammalian cell lines, indicating the species-specific toxicity of CuNPs. This study revealed that the morphologies, ion release rate of NPs as well as the species-specific vulnerabilities of cells should all be considered when explaining and extrapolating toxicity test results among particles and among species.
    https://doi.org/10.3109/17435390.2013.790997
  • African Journal of Ecology
    2014

    Variation in plant biodiversity across sacred groves and fallows in Western Highlands of Cameroon

    C. M. Tankou, Geert de Snoo, Hans H. de Iongh, Gerard A. Persoon
    The study was conducted to compare species richness and diversity in different ecosystems and abiotic factors. The results showed that the sacred groves had a plant genetic diversity composed of a total of 42, 65 and 82 ethno-botanical species of herbs, shrubs and trees, respectively, with varied qualities. There were six herbaceous species common in the fallow ecosystem and the sacred groves, 35 herbaceous species found in the sacred grove and absent in the fallow vegetation and 70 herbaceous species in the fallow vegetation and absent in the ground layer of the sacred groves. Thirty-two regenerated species and 49 nonregenerated tree species were found in the sacred groves. The herbaceous -diversity was significantly higher in the fallows than the sacred groves at the low altitude. The tree species richness was higher at the low altitude compared to the high altitude with tree -diversity increasing with altitude. Varying combinations of soil pH, total P, total K, CEC and slope per cent were related to some of the parameters evaluated. Biodiversity changes in the sacred groves may be governed by biophysical drivers, while a combination of human and biophysical explained the variation in rotational fallow vegetation.
    https://doi.org/10.1111/aje.12079
  • Ecological Indicators
    2014

    Theoretical exploration for the combination of the ecological, energy, carbon, and water footprints: Overview of a footprint family

    K. Fang, R. Heijungs, Geert de Snoo
    Over the past two decades, a continuously expanding list of footprint-style indicators has been introduced to the scientific community with the aim of raising public awareness of how humanity exerts pressures on the environment. A deeper understanding of the connections and interactions between different footprints is required in an attempt to support policy makers in the measurement and choice of environmental impact mitigation strategies. Combining a selection of footprints that address different aspects of environmental issues into an integrated system is, therefore, a natural step. This paper starts with the idea of developing a footprint family from which most important footprints can be compared and integrated. On the basis of literature review in related fields, the ecological, energy, carbon, and water footprints are employed as selected indicators to define a footprint family. A brief survey is presented to provide background information on each of the footprints with an emphasis on their main characteristics in a comparative sense; that is, the footprints differ in many aspects more than just the impacts they are addressed. This allows the four footprints to be complementarily used in assessing environmental impacts associated with natural resource use and waste discharge. We evaluate the performance of the footprint family in terms of data availability, coverage complementarity, methodological consistency, and policy relevance and propose solutions and suggestions for further improvement. The key conclusions are that the footprint family, which captures a broad spectrum of sustainability issues, is able to offer a more complete picture of environmental complexity for policy makers and, in particular, in national-level studies. The research provides new insights into the distinction between environmental impact assessment and sustainability evaluation, properly serving as a reference for multidisciplinary efforts in estimating planetary boundaries for global sustainability. (C) 2013 Elsevier Ltd. All rights reserved.
    https://doi.org/10.1016/j.ecolind.2013.08.017
  • Occupational and Environmental Medicine
    2014

    Expert assessment of historical crop specific pesticide use in the Netherlands

    Maartje Brouwer, A. Huss, Roel C.H. Vermeulen, P. C. G. Nijssen, Geert de Snoo, H. Kromhout
    Objectives Retrospective assessment of environmental pesticide exposure is challenging. Exposure measurements or information on crop-specific pesticide use are often lacking historically. We applied expert assessment to reconstruct historical pesticide use patterns in the Netherlands, and evaluated reliability and accuracy of this procedure. Methods For six main crops in the Netherlands, two experts per crop individually rated the probability (percentage of farmers applying) and frequency of use of authorised active ingredients between 1961 and 2005 per 5-year period. Inter-rater agreement was investigated by the percentage overall agreement and weighted Cohen's kappa's (kappa(W)). Experts' ratings were compared with self-reported pesticide use from recent farmer surveys to determine accuracy of the ratings. Results Inter-rater agreement on the probability of use varied between crops (kappa(W) 0.25 to 0.69), as well as agreement on the frequency of use (kappa(W) 0.32 to 0.64). Inter-rater agreement was marginally higher for herbicides and fungicides than insecticides. Comparisons with survey data indicated fair to good accuracy of the experts' ratings for the probability (kappa(W) 0.48 to 0.65) and frequency of use (kappa(W) 0.38 to 0.68). For all crops except fruit, the specificity of the experts' ratings was higher than the sensitivity. Conclusions Overall inter-rater agreement between experts was fair to good and experts' ratings were reasonably accurate. Results of this study indicate that expert assessment can be used to derive information on historical pesticide use, which is essential for epidemiological studies evaluating the effect of (past) environmental exposure to pesticides on health.
    https://doi.org/10.1136/oemed-2014-102189
  • PLoS One
    2014

    Social Structure of Lions (Panthera leo) Is Affected by Management in Pendjari Biosphere Reserve, Benin

    E. A. Sogbohossou, H. Bauer, A. Loveridge, P. J. Funston, Geert de Snoo, B. Sinsin, Hans H. de Iongh
    Lion populations have undergone a severe decline in West Africa. As baseline for conservation management, we assessed the group structure of lions in the Pendjari Biosphere Reserve in Benin. This reserve, composed of one National Park and two Hunting Zones, is part of the WAP transboundary complex of protected areas. Overall mean group size was 2.6 +/- 1.7 individuals (n = 296), it was significantly higher in the National Park (2.7 +/- 1.7, n = 168) than in the Hunting Zones (2.2 +/- 1.5, n = 128). Overall adult sex ratio was even, but significantly biased towards females (0.67) in the National Park and towards males (1.67) in the Hunting Zones. Our results suggest that the Pendjari lion population is affected by perturbations, such as trophy hunting.
    https://doi.org/10.1371/journal.pone.0084674
  • Global Ecology and Conservation
    2014

    Impact of severe climate variability on lion home range and movement patterns in the Amboseli ecosystem, Kenya

    J. H. Tuqa, P. J. Funston, C. Musyoki, G. O. Ojwang, N. N. Gichuki, H. Bauer, Will Tamis, Stephanie Dolrenry, Maarten van't Zelfde, Geert de Snoo, Hans H. de Iongh
    In this study, we were interested in understanding if droughts influence the home range of predators such as lions, and if it does, in what ways the droughts influenced lions to adjust their home range, in response to prey availability. We monitored movements of ten lions fitted with GPS-GSM collars in order to analyze their home range and movement patterns over a six year period (2007-2012). We assessed the impact of a severe drought on the lion home range and movement patterns in the Amboseli ecosystem. There was a strong positive correlation between the home range size and distance moved in 24 h before and during the drought (2007-2009), while after the drought there was a significant negative correlation. A weak positive correlation was evident between the lion home range and rainfall amounts (2010-2012). The male and female home ranges varied over the study period. The home range size and movement patterns coincided with permanent swamps and areas of high prey density inside the protected area. Over the course of the dry season and following the drought, the ranges initially shrank and then expanded in response to decreasing prey densities. The lions spent considerable time outside the park boundaries, particularly after severe the drought. We conclude that under conditions of fragmented habitats, severe climate conditions create new challenges for lion conservation due to effects on prey availability and subsequent influences on carnivore species ranging patterns. Stochastic weather patterns can force wide-ranging species beyond current reserve boundaries, into areas where there will be greater conflicts with humans. (C) 2014 The Authors. Published by Elsevier B. V.
    https://doi.org/10.1016/j.gecco.2014.07.006
  • Journal of Ornithology
    2014

    Habitat use and diet of Skylarks (Alauda arvensis) wintering in an intensive agricultural landscape of the Netherlands

    F. Geiger, A. Hegemann, J.M. Gleichman, H. Flinks, Geert de Snoo, S. Prinz, B. Irene Tieleman, Frank Berendse
    In recent decades, Skylark (Alauda arvensis) populations in Europe have declined sharply due to agricultural intensification. Insufficient reproduction rates are one reason. Increased winter mortality may also be important, but studies outside the breeding season are scarce and mostly limited to the UK. We studied habitat selection of wintering Skylarks in an agricultural area in the Netherlands. We monitored Skylarks between November 2008 and March 2009 on 10 survey plots including 77 different arable fields and permanent grasslands and covering in total 480 ha. We simultaneously measured food availability, vegetation structure and field boundary characteristics. We also analysed 158 faecal pellets collected on potato and cereal stubble fields to relate Skylark diet to seasonal changes in food availability and foraging habitat. We show that cereal stubble fields larger than 4.3 ha, surrounded by no or low boundary vegetation and a density of dietary seeds of more than 860 seeds m(-2), were most suitable for wintering Skylarks. Skylark group densities were low on permanent grasslands and on maize stubble fields. Densities of dietary seeds were highest in soils of potato stubble fields followed by cereal stubble fields, grasslands and maize stubble fields. Skylarks showed a strong preference for cereal grains, but their proportion in the diet fell sharply at the end of November, indicating that cereal grains were depleted and birds had to switch to less profitable food sources, such as weed seeds and leaves. We conclude that Skylarks wintering in agricultural landscapes possibly suffer from a lack of energy-rich food sources and only a few fields provide sufficient food. Conservation measures should strive to improve the wintering situation by creating food-rich habitats such as over-winter stubble with a rich layer of weeds on large fields and localised in open areas.
    https://doi.org/10.1007/s10336-013-1033-5
  • Ardea
    2014

    Do field margins enrich the diet of the Eurasian Skylark Alauda arvensis on intensive farmland?

    H. J. Ottens, M. W. Kuiper, H. Flinks, Jasper van Ruijven, Henk Siepel, B. J. Koks, Frank Berendse, Geert de Snoo
    To help restore food availability for birds, arable field margins (extensively managed strips of land sown with grasses and forbs) have been established on European farmland. In this study we describe the effect of field margins on the diet of Eurasian Skylark nestlings and adults living on intensively managed Dutch farmland. We tested the hypotheses that field margins offer a higher diversity of invertebrate prey than intensively managed crops, and that the diet of nestlings receiving food from field margins will therefore be more diverse than that of other nestlings. Field margins had a greater variety of invertebrate prey groups to offer than the intensively managed crops. Coleoptera were the most frequently and most abundantly eaten prey group by both adults and nestlings. Together, Coleoptera, Diptera, Lepidoptera, Hymenoptera and Araneae accounted for 91% of the nestling diet. Nestlings ate larger prey items and a larger proportion of larvae than adults. Almost 75% of both adults and nestlings consumed plant material, perhaps indicating a scarcity of invertebrate resources. When provided with food from field margins, the mean number of invertebrate orders in the nestling diet increased significantly from 4.7 to 5.5 and the number of families from 4.2 to 5.8 per sample. Thus, birds that used field margins for foraging could indeed provide their young with more invertebrate prey groups than birds only foraging in crops and grassland.
    https://doi.org/10.5253/arde.v102i2.a6
  • Environmental Toxicology and Chemistry
    2014

    Impact of imidacloprid on Daphnia magna under different food quality regimes

    O. Ieromina, Wjgm Peijnenburg, Geert de Snoo, Jutta Müller, T. P. Knepper, Martina G. Vijver
    Aquatic ecosystems are characterized by fluctuating conditions that have direct effects on aquatic communities but also indirect influences such as changing the toxicity of chemicals. Because the effect of food quality on pesticide toxicity has rarely been studied, in the present study Daphnia magna juveniles supplied with 4 different food quality levels were exposed to a range of imidacloprid concentrations for 21 d. Food quality was expressed as carbon:phosphorus ratios of algae Pseudokirchneriella subcapitata (C:P 35, C:P 240, C:P 400, and C:P 1300). Survival, growth rates, and reproduction of D. magna were monitored, and the combined effects of imidacloprid exposure and the phosphorus content of algae were analyzed. A stronger effect on survival was observed at the P-deficient diet (C:P 1300), confirmed by lower 10% effect concentration (EC10) values at days 7, 9, 15, and 21 compared with diets with higher phosphorus contents. Similarly, the growth rate was reduced when D. magna were supplied with algae of low phosphorus content at imidacloprid exposure conditions. The highest reproductive output was observed for D. magna fed the optimal phosphorus diet (C:P 240), both at control and exposed conditions. Poor food quality increased the sensitivity of nontarget species to pesticide exposure, potentially leading to an underestimation of adverse effects on aquatic communities in the field. Environ Toxicol Chem 2014;33:621-631. (c) 2013 SETAC
    https://doi.org/10.1002/etc.2472
  • Land Use Policy
    2014

    There is an I in nature: The crucial role of the self in nature conservation

    A. M. Lokhorst, Céline Hoon, R. le Rutte, Geert de Snoo
    In this paper we analyze the social-psychological determinants of private nature conservation. As a theoretical framework we use the Theory of Planned Behavior, to which the concepts connectedness to nature, self-identity, and place attachment were added. 94 landowners participated in our survey. Results of this pilot study show that perceived behavioral control, self-identity and connectedness to nature are the key factors influencing the intention to conserve. The more farmers feel that they are capable of conserving nature on their farm, the more they see themselves as conservationists, and the more they feel connected to nature, the more likely they are to intend to conserve. An important finding is that self-identity mediates the relation between CNS and conservation intentions. This implies that with an increased connectedness to nature, people come to see themselves as conservationists and this in turn influences their intentions. Of course, these results need to be replicated and validated across different contexts. We discuss the implications of this study for future research and policy. (c) 2014 Elsevier Ltd. All rights reserved.
    https://doi.org/10.1016/j.landusepol.2014.03.005
  • Netherlands Journal of Agricultural Science
    2014

    Analysing the farm level economic impact of GM corn in the Philippines

    M. M. Afidchao, C.J.M. Musters, A. Wossink, O. F. Balderama, Geert de Snoo
    This paper analyses the farm economic viability of genetically modified (GM) corn in the Philippines. Data was collected from 114 farmers in Isabela province including non-GM, Bacillus thuringiensis (Bt), herbicide tolerant (HT) and BtHT corn farmers. Results of univariate analysis showed that non-GM corn was not statistically different from Bt, BtHT and HT corn in terms of production output, net income, production-cost ratio and return on investment. Multivariate econometric analysis for the agronomic input variables showed a higher return on investment for Bt corn as the only significant difference between seed types. Next, pest occurrence and severity variables were included in the regression to address endogeneity. The Blinder-Oaxaca decomposition method was used to further investigate differences between growers of BtHT corn and non-GM corn into an endowment and a coefficient effect. The decomposition analysis showed that BtHT corn has a negative impact on return on investment as revealed by the negative signs of the overall mean gap and the characteristics and coefficient components. In contrast, the overall mean gap for net income indicated that adopting BtHT corn could potentially increase non-GM growers' income mainly from better control of corn borer pest even though mean levels of borer occurrence are lower for non-GM growers. (C) 2014 Royal Netherlands Society for Agricultural Sciences. Published by Elsevier B.V. All rights reserved.
    https://doi.org/10.1016/j.njas.2014.05.008
  • International Dairy Journal
    2014

    Determinants And Impacts Of Human Mobility Dynamics In The Western Highlands Of Cameroon

    C. M. Tankou, Hans H. de Iongh, Gerard A. Persoon, ME de Bruijn, Geert de Snoo
  • Journal of Cleaner Production
    2014

    A framework for deciding on the inclusion of emerging impacts in life cycle impact assessment

    S. Cucurachi, R. Heijungs, Wjgm Peijnenburg, J. F. B. Bolte, Geert de Snoo
    As technology progresses, so does the concern about the potential health impacts on humans and biodiversity that go in hand with technological development. Emerging new impacts that are characteristic of the anthropocene require more attention in current life cycle assessment (LCA), a framework in which many relevant impact assessment models are still missing. More attention, more data and more concern require the LCA community to intervene and to start or increase the modelling efforts to accommodate new impacts in LCA. To date the process of inclusion of new impacts in LCA has not yet been formalised. To deal with this process, a framework is here proposed and tested through the analysis of three emerging impact categories, noise, ecological light pollution (ELP) and radio-frequency electromagnetic fields (RF-EMF). We show that any development must start from a careful study of the theories and investigations from other specialist fields of science than the field of LCA. The gathering of such information is fundamental to assess the maturity of the impacts, their importance and the quality of the evidence that is available. In addition, this information has to be bridged to the computational structure of LCA, to check whether the physical properties of new impacts may be adjusted to the basics of LCA. We discuss the three new potential impact categories as a paradigm for action for any new development in LCA. (C) 2014 Elsevier Ltd. All rights reserved.
    https://doi.org/10.1016/j.jclepro.2014.05.010
  • Environmental Pollution
    2014

    Population responses of Daphnia magna, Chydorus sphaericus and Asellus aquaticus in pesticide contaminated ditches around bulb fields

    O. Ieromina, Wjgm Peijnenburg, Geert de Snoo, Martina G. Vijver
    The goal of this study was to investigate the effects of ambient concentrations of pesticides combined with abiotic factors on the key aquatic species Daphnia magna, Chydorus sphaericus and Asellus aquaticus by means of 21 days field exposure experiments. In situ bioassays were deployed in ditches around flower bulb fields during spring and autumn 2011-2012. The results showed that phosphate was the most variable parameter followed by pesticides expressed as toxic units, as the main factors explaining differences between sites. Variation in reproduction and growth of cladoceran D. magna was largely explained by nutrients, whereas dissolved oxygen contributed mostly to variations in reproduction of C sphaericus. Dissolved organic carbon contributed to variations in growth of the detrivore A. aquaticus. It is concluded that abiotic stressors rather than pesticides contributed significantly to the performance of aquatic invertebrates. (C) 2014 Elsevier Ltd. All rights reserved.
    https://doi.org/10.1016/j.envpol.2014.05.020
  • Biodiversity and Conservation
    2014

    Structure, composition and diversity of plant communities in FSC-certified, selectively logged forests of different ages compared to primary rain forest

    Arbainsyah Insya, Hans H. de Iongh, Wawan Kustiawan, Geert de Snoo
    The impact of logging on plant communities was studied in forest that has been logged selectively 1, 5 and 10 years previously (following a certified procedure): diversity was compared with that of primary rain forest in the Berau region of East Kalimantan, Indonesia. Four sets of 20 transects located within an area of 6 ha were sampled for all trees, saplings and seedlings, and records were made of topographic position, structure, composition and species diversity. There was a high level of floristic similarity between primary forests at the study sites compared to primary forest elsewhere in Kalimantan. The impact of logging is therefore likely to be the most important factor determining any differences between the plant communities of the selectively logged and primary forest sites. We found differences in species composition and abundance of most plants between selectively logged and primary forest. Overall, stem densities of trees in the primary forest were higher than in the three selectively logged forest sites. Stem densities of saplings were equivalent in all four forests. Seedling stem densities were higher in the forest site logged 10 years previously than in primary forest. Our results showed that the forests logged selectively under certified regimes still have a high plant diversity, possibly indicating that biodiversity values may be conserved by following certification procedures.
    https://doi.org/10.1007/s10531-014-0732-4
  • PLoS One
    2014

    Patterns in Nuclear and Mitochondrial DNA Reveal Historical and Recent Isolation in the Black-Tailed Godwit (Limosa limosa)

    K. B. Trimbos, C. Doorenweerd, Ken Kraaijeveld, C.J.M. Musters, N. M. Groen, P. de Knijff, Theunis Piersma, Geert de Snoo
    On the basis of morphological differences, three subspecies of Black-tailed Godwit (Limosa limosa) have been recognized (L. l. limosa, L. l. islandica and L. l. melanuroides). In previous studies mitochondrial DNA (mtDNA) sequence data showed minimal genetic divergence between the three subspecies and an absence of sub-structuring within L. l. limosa. Here, population genetic structure and phylogeographic patterns have been analyzed using COI, HVR1 and HVR2 mtDNA sequence data as well as 12 microsatellite loci (nuDNA). The nuDNA data suggest genetic differentiation between L. l. limosa from Sweden and The Netherlands, between L. l. limosa and L. l. islandica, but not between L. l. limosa and L. l. melanuroides. However, the mtDNA data were not consistent with the nuDNA pattern. mtDNA did support a split between L. l. melanuroides and L. l. limosa/L. l. islandica and also demonstrated two L. l. limosa haplotype clusters that were not geographically isolated. This genetic structure can be explained by a scenario of isolation of L. l. melanuroides from L. l. limosa in Beringia during the Last Glacial Maximum. During the Pleistocene separation of L. l. islandica from L. l. limosa occurred, followed by colonization of Iceland by the L. l. islandica during the Holocene. Within L. l. limosa founder events, followed by population expansion, took place during the Holocene also. According to the patterns observed in both markers together and their geographic separation, we propose that the three traditional subspecies indeed represent three separate genetic units.
    https://doi.org/10.1371/journal.pone.0083949
  • Biological Conservation
    2014

    The effectiveness of ditch banks as dispersal corridor for plants in agricultural landscapes depends on species' dispersal traits

    W. F. A. van Dijk, Jasper van Ruijven, Frank Berendse, Geert de Snoo
    The effectiveness of agri-environment schemes (AES) in enhancing biodiversity in agricultural landscapes is still strongly debated. In the Netherlands, one of the most widely implemented AES is the management of ditch banks to enhance plant species diversity. Previous research has shown that this type of AES has not led to increases in plant diversity. However, this work also showed that the success of this type of AES may depend on the presence of source populations in the surrounding areas. In this study we investigated if species-rich nature reserves can act as seed sources for agricultural ditch banks under AES and whether this function of nature reserves differs among plant species with different dispersal capacities. We used data collected by farmers over a 10 year period to analyse trends in species richness of target plants and in different dispersal groups in ditch banks under AES at different distances from nature reserves. Our results demonstrate that nature reserves can act as species rich sources in agricultural landscapes and that adjacent AES ditch banks can facilitate the colonisation of the surrounding agricultural landscape. However, the suitability of ditch banks as corridors depends on the dispersal capacity of a species. Particularly water-dispersed species clearly spread from nature reserves into the surrounding agricultural landscape along ditches. In contrast, species without adaptations to disperse over long distances do not show these spatiotemporal patterns. (C) 2014 Elsevier Ltd. All rights reserved.
    https://doi.org/10.1016/j.biocon.2014.01.006
  • Environment International
    2013

    A review of the ecological effects of radiofrequency electromagnetic fields (RF-EMF)

    S. Cucurachi, Will Tamis, Martina G. Vijver, Wjgm Peijnenburg, J. F. B. Bolte, Geert de Snoo
    Objective: This article presents a systematic review of published scientific studies on the potential ecological effects of radiofrequency electromagnetic fields (RF-EMF) in the range of 10 MHz to 3.6 GHz (from amplitude modulation, AM, to lower band microwave, MW, EMF). Methods: Publications in English were searched in ISI Web of Knowledge and Scholar Google with no restriction on publication date. Five species groups were identified: birds, insects, other vertebrates, other organisms, and plants. Not only clear ecological articles, such as field studies, were taken into consideration, but also biological articles on laboratory studies investigating the effects of RF-EMF with biological endpoints such as fertility, reproduction, behaviour and development, which have a clear ecological significance, were also included. Results: Information was collected from 113 studies from original peer-reviewed publications or from relevant existing reviews. A limited amount of ecological field studies was identified. The majority of the studies were conducted in a laboratory setting on birds (embryos or eggs), small rodents and plants. In 65% of the studies, ecological effects of RF-EMF (50% of the animal studies and about 75% of the plant studies) were found both at high as well as at low dosages. No clear dose-effect relationship could be discerned. Studies finding an effect applied higher durations of exposure and focused more on the GSM frequency ranges. Conclusions: In about two third of the reviewed studies ecological effects of RF-EMF was reported at high as well as at low dosages. The very low dosages are compatible with real field situations, and could be found under environmental conditions. However, a lack of standardisation and a limited number of observations limit the possibility of generalising results from an organism to an ecosystem level. We propose in future studies to conduct more repetitions of observations and explicitly use the available standards for reporting RF-EMF relevant physical parameters in both laboratory and field studies. (C) 2012 Elsevier Ltd. All rights reserved.
    https://doi.org/10.1016/j.envint.2012.10.009
  • Fire Ecology
    2013

    Lepidoptera pest species response to mid-summer fire

    Tracy R. Evans, C.J.M. Musters, E. D. Cashatt, Geert de Snoo
    In the American Midwest, summer fires are infrequent, and there is little information on their impact on ecosystems. After an accidental wildfire in a 20 ha grassland restoration, new growth provided effective substrate for the noctuid species corn earworm, Helicoverpa zea (Boddie), and tobacco budworm, Heliothis virescens (Fabricius). These agricultural pests feed on a number of important crop species and have been implicated in crop losses of up to 50 %. Invertebrate collections were made at 16 days, 45 days, 70 days, and 101 days post fire. A comparison of burned and unburned areas at 70 days post fire show 18 times the number of Lepidoptera larvae collected in pitfall traps in the burned area compared to the adjacent unburned area of the grasslands. These findings demonstrate that a mid-summer fire can affect the abundance of economically important insects.
    https://doi.org/10.4996/fireecology.0903025
  • Condor
    2013

    Breeding performance of the grasshopper buzzard (butastur rufipennis) in a natural and a human-modified West African savanna

    R. Buij, K. Kortekaas, Roderick van Krimpen, Rien van Wijk, S. van der Zanden, Hans H. de Iongh, Ignas M. A. Heitkönig, Geert de Snoo, J. Komdeur
    Few studies have examined raptor reproduction in response to land-use change in sub-Saharan Africa, hampering conservation efforts to address regional declines. To further our understanding of mechanisms underlying the dramatic declines of West African raptors, we examined the relationship between environmental conditions, nest density, and measures of reproduction in the Grasshopper Buzzard (Butastur rufipennis). Analyses were based on 244 nest sites divided between transformed and natural habitat in northern Cameroon. At the landscape scale, nest density increased with the density of preferred nest trees. Nests were more widely spaced in transformed than in natural habitat. Dispersion was adjusted to differences in availability of small mammals, which was negatively associated with distance to nearest neighbor, and in the area under cultivation, which was positively associated with distance to nearest neighbor. Productivity was positively associated with rainfall, canopy shielding the nest, availability of grasshoppers, and the nest's visibility from ground level; canopy shielding, grass cover, rainfall, and distance to nearest neighbor were positively associated with nest success. In natural habitat, losses of eggs and nestlings to natural predators were greater than in transformed habitats, while losses through human predation were small. Productivity and nest success were unaffected by land use because of the opposing effects of greater predation pressure, closer spacing of nests, and more food in natural habitat than in transformed habitat. Thus transformed habitat may provide adequate breeding habitat for the Grasshopper Buzzard, but declining rainfall and intensifying anthropogenic land use are likely to affect future reproductive output.
    https://doi.org/10.1525/cond.2012.120049
  • Pest Management Science
    2013

    Asian corn borer (ACB) and non-ACB pests in GM corn (Zea mays L.) inthe Philippines

    M. M. Afidchao, C.J.M. Musters, Geert de Snoo
    Background The Asian corn borer (ACB), Ostrinia furnacalis (Guenee), has become the most damaging pest in corn in south-east Asia. Corn farmers in the Philippines have incurred great yield losses in the past decades because of ACB infestation. Bacillus thuringiensis (Bt) and Bt herbicide-tolerant (BtHT) corns have been developed to reduce borer attacks worldwide. This study assessed the extent of ACB and non-ACB pest infestations in both GM and non-GM corn in Isabela Province, the Philippines. Specific aims were to reinvestigate the efficacy of Bt corn in controlling ACB, to evaluate what parts of Bt corn plants are susceptible to ACB, to monitor the potential development of ACB resistance and to evaluate whether secondary pests dominate in an ACB-free Bt corn environment. The study involved preparatory interviews with farmers, site selection, field scouting and visual inspection of 200 plants along 200 m transect lines through 198 cornfields. Results Bt corn can efficiently reduce the ACB pest problem and reduce borer damage by 44%, to damage levels in Bt and BtHT corn of 6.8 and 7% respectively. The leaves of Bt corn were more susceptible, while cobs of Bt corn were less affected by ACB. Non-ACB pests were common in Bt toxin-free cornfields and reduced in non-GM cornfields where ACB was abundant. No secondary pest outbreaks were found in ACB-free Bt cornfields. Conclusion Bt and BtHT corn hybrids containing the Cry1Ab protein performed well in Isabela Province. Reduced cob damage by ACB on Bt fields could mean smaller economic losses even with ACB infestation. The occurrence of ACB in Bt and BtHT cornfields, although at a moderate and insignificant level, could imply the potential development of resistance to Bt toxin. (c) 2012 Society of Chemical Industry
    https://doi.org/10.1002/ps.3471
  • Revue De Métallurgie-Cahiers d'Informations Techniques
    2013

    The footprint family: comparison and interaction of the ecological, energy, carbon and water footprints

    K. Fang, R. Heijungs, Geert de Snoo
    The year of 2012 marks the 20th anniversary since the concept of ecological footprint was introduced to the global community for the first time. Nowadays footprint studies have gained extensive debates as well as popularity. In this paper, we define the footprint family as an indicator system of selected footprints that measure some aspects of human impacts on the environment. A relatively comprehensive introduction and comparison of four key footprints is represented by listing their characteristics in different aspects. The interaction among these footprints within the footprint family is classified into three types: overlap, contradiction and complement. The description of each type is provided in detail. Limitations and uncertainties of the footprint family, and priorities for further improvement are also performed. This research makes a preliminary attempt at developing the conceptual framework for the footprint family, which allows us to examine the performance of footprints combination. The footprint family will serve as a tool for integrating footprints on human impacts assessment, and a support for environmental decision-making.
    https://doi.org/10.1051/metal/2013051
  • Conservation Letters
    2013

    Toward effective nature conservation on farmland: making farmers matter

    Geert de Snoo, Irina Herzon, H. Staats, R. J. F. Burton, S. Schindler, Jerry van Dijk, A. M. Lokhorst, James M. Bullock, M. Lobley, T. Wrbka, G. Schwarz, C.J.M. Musters
    Until now the main instrument to counteract the loss of biodiversity and landscape quality in the European countryside has been agri-environment schemes (AES), which offer short-term payments for performing prescribed environmental management behaviors. In our opinion this approach is, in its current set-up, not a sustainable way of enhancing biodiversity and landscape quality. Here we will argue that conservation in agricultural areas is also a social challenge. To change farmers' behaviors toward more sustainable conservation of farmland biodiversity, instruments should aim to influence individual farmer's motivation and behavior. We should aim to place farmland biodiversity in the hands and minds of farmers.
    https://doi.org/10.1111/j.1755-263X.2012.00296.x
  • Plant Biology
    2013

    Morphological markers for the detection of introgression from cultivated into wild carrot (Daucus carota L.) reveal dominant domestication traits

    C. Grebenstein, S. P. Kos, T.J. De Jong, Will Tamis, Geert de Snoo
    Hybridisation and subsequent introgression have recently received much attention in the context of genetically modified crops. But cropwild hybrid detection in the field can be difficult, as most domestication traits seem to be recessive, and the hybrid phenotype may also depend on the direction of the cross or environmental factors. Our aim was to develop a reliable set of morphological markers that differ between two wild and 13 cultivated carrots (Daucus carota L.) and to evaluate their inheritance in hybrid lines. We then examined these morphological markers in four F1 hybrids obtained by fertilising plants from the two wild accessions with pollen from two common carrot cultivars. Of the 16 traits that differed between the two carrot subspecies, three took intermediate values in the hybrids, eight resembled the cultivar parent (dominant domestication traits), two resembled the wild parent (domestication traits recessive), and three were not significant or growth condition-dependent. Root:shoot ratio was seven times higher for cultivars than for wild plants, while still attaining equivalent total dry weight, which shows that dry matter production by the shoot is much higher in cultivars than in wild plants. High root:shoot ratios were also present in the hybrids. While we found no maternal effects, the type of cultivar used for pollination had an impact on hybrid characteristics. The morphological markers developed here provide insights into the mode of inheritance of ecologically relevant traits and can be useful for pre-screening wild populations for hybrid detection prior to genetic analysis.
    https://doi.org/10.1111/j.1438-8677.2012.00662.x
  • International Journal of Agricultural Research
    2013

    Soil quality assessment of cropping systems in the Western Highlands of Cameroon

    C. M. Tankou, Geert de Snoo, Hans H. de Iongh, Gerard A. Persoon
  • Aspects of Applied Biology
    2013

    A stakeholders' view on indicators of farmers' biodiversity performance. ID - 20133158776

    J. F. Admiraal, P. Post, C.J.M. Musters, Geert de Snoo
    The last decades have seen an increasing pressure on biodiversity in agricultural lands. The farmer plays a crucial role in maintaining biodiversity. However, opinions on systems of rating or rewarding of farmers for their performance in biodiversity management are divided. A study was conducted to elucidate the opinions of stakeholders of agricultural production on what would be proper indicators with which to rate a farmer's performance in stimulating biodiversity on his property. Four different stakeholders were chosen to express their opinions: farmers' organizations, nature conservation organizations, governmental organizations and food companies. Thirty different indicators were presented to the stakeholders and these indicators were grouped in three different categories: "A farmer's effort in nature management", "The preconditions necessary to obtain an enhanced performance" and "The attained nature results". By grading the thirty indicators, we found the revealed preferences for these three categories. In addition, in a stated preferences test the chain parties were asked to rank the three categories in importance. The results show clear differences between the revealed and stated preferences of stakeholders to indicator types. This indicates that the stakeholders have opinions about the indicator categories that do not conform to their stated preferences. Furthermore, the revealed preferences test shows consistently high ratings for the indicator groups "preconditions" and "nature results", with a significant difference between those indicators groups and the "effort" group. Both results should be taken into account in the design of rating systems. Our study suggests that a rating system based on the preconditions necessary to obtain an enhanced performance and the attained biodiversity results will be experienced as most acceptable throughout the chain of agricultural production.
  • Aspects of Applied Biology
    2013

    Including ecosystem sustainability in the economic valuation of biodiversity.

    J. F. Admiraal, C.J.M. Musters, A. Wossink, W.T. de Groot, Geert de Snoo
    Economic valuation of nature has become a pragmatic and popular approach in ecosystem management, yet criticisms have been raised. One major point of critique is that economic valuation bases the value of ecosystems only on the monetary flow of human benefits of ecosystem services and consequently ignores questions of sustainable use of ecosystems. This paper explains why economic valuation by itself is in principle an inadequate concept to guide sustainable use of ecosystems and proposes a framework that allows a combination of traditional economic valuation with management of ecosystems guided by ecological theory. The key elements of this framework are theoretical insights about ecosystem resilience as essential ecological theory that needs to be taken into account in addition to economic valuation to fully capture ecosystem sustainability and elements of portfolio theory. Portfolio theory puts economic valuation in a framework where investment in biodiversity can cover functional diversity and "mobile links" in order to maintain ecosystem resilience and so can foster sustainable use of ecosystems.
  • Agriculture, Ecosystems and Environment
    2013

    Field margins as foraging habitat for skylarks (Alauda arvensis) in the breeding season

    M. W. Kuiper, H. J. Ottens, L. Cenin, A. P. Schaffers, Jasper van Ruijven, B. J. Koks, Frank Berendse, Geert de Snoo
    Agri-environment schemes have been established in many European countries to counteract the ongoing decline of farmland birds. In this study, the selection of foraging habitat by breeding skylarks was examined in relation to agri-environmental management on Dutch farmland. Field margin use was quantified and, based on the observed flight distances, the appropriateness of the current spatial arrangement of field margins in the study landscape was evaluated. Skylarks preferred field margins for foraging over all other habitat types relative to their surface area within the territories. The visiting rate of field margins decreased with increasing distance to the nest, and especially dropped markedly when the distance between the nest and a field margin exceeded 100 m. Analysis of the current spatial arrangement of field margins in the landscape suggested that the area of skylark breeding habitat within 100 m of a field margin could be increased by 46%. This was due to the placement of field margins alongside unsuitable breeding habitat and to the positioning of field margins at short distances from each other. The efficiency of agri-environmental management for skylarks can likely be improved by a more careful spatial arrangement of field margins in the landscape. (C) 2013 Elsevier B.V. All rights reserved.
    https://doi.org/10.1016/j.agee.2013.03.001
  • Ibis
    2013

    Intronic variation at the CHD1-Z gene in Black-tailed Godwits Limosa limosa limosa: correlations with fitness components revisited

    K. B. Trimbos, Rosemarie Kentie, M. Van der Velde, Jos C.E.W. Hooijmeijer, C. Poley, C.J.M. Musters, Geert de Snoo, Theunis Piersma
    Recently, Schroeder etal. (2010, Ibis 152: 368-377) suggested that intronic variation in the CHD1-Z gene of Black-tailed Godwits breeding in southwest Friesland, The Netherlands, correlated with fitness components. Here we re-examine this surprising result using an expanded dataset (2088 birds sampled from 2004 to 2010 vs. 284 birds from 2004 to 2007). We find that the presence of the Z* allele (9% of the birds) is not associated with breeding habitat type, egg size, adult survival, adult body mass or adult body condition. The results presented here, when used in synergy with the previously reported results by Schroeder etal., suggest that there might be a tendency towards female adults with the Z* allele laying earlier clutches than adult females without the Z* allele. The occurrence of the Z* allele was also associated with a higher chick body mass and return rate. Chicks with the Z* allele that had hatched early in the breeding season were heavier at birth than chicks without the Z* allele and chicks with the Z* allele that had hatched late. Collectively, the results suggest that variation in the CHD1-Z gene may indeed have arisen as a byproduct of selection acting on females during the egg fase and on chicks during the rearing stages of the reproductive cycle.
    https://doi.org/10.1111/ibi.12057
  • Basic and Applied Ecology
    2013

    Temporal effects of agri-environment schemes on ditch bank plant species

    W. F. A. van Dijk, A. P. Schaffers, L. Leewis, Frank Berendse, Geert de Snoo
    Many of the agri-environment schemes (AES) implemented in the Western Peat District of the Netherlands have as their objective the conservation of the diversity of ditch bank plants. We investigated the effects of AES on ditch bank species in this area, using a dataset collected by 377 farmers who managed and monitored ditch banks during a 10-year period. We found that species richness has increased minimally over the last 10 years in ditch banks. Yet, we found no differences in increases in time between ditch banks with and without AES. In both ditch bank types plant species composition changed to species with higher nitrogen tolerance. Furthermore, species that disperse over long distances by water increased, whereas species with no capacity to disperse over long distances declined in both ditch bank types. This indicates that changes in vegetation composition in ditch banks are affected by other factors than AES.
    https://doi.org/10.1016/j.baae.2013.04.001
  • Ecological Economics
    2013

    More than total economic value: How to combine economic valuation of biodiversity with ecological resilience

    J. F. Admiraal, A. Wossink, W.T. de Groot, Geert de Snoo
    The assessment of total economic value has become a pragmatic and popular approach in nature valuation, yet criticisms have been raised. One major point of critique is that total economic value bases the monetary value of ecosystems purely on the flow of human benefits of services of ecosystems and consequently ignores questions of sustainable use of natural capital per se. This paper explains why total economic value by itself is in principle an inadequate concept to guide sustainable use of ecosystems and gives an overview of essential ecological theory that needs to be taken into account in addition to total economic value to fully include ecosystem sustainability. The paper concludes with a framework for combining ecological theory with economic valuation. The key elements here are theoretical ecological insights about ecosystem resilience and portfolio theory which offers an economic perspective on investment in biodiversity. Portfolio theory puts total economic value in a framework where investment in biodiversity is expanded to cover functional diversity and mobile link species in order to maintain ecosystem resilience and so fosters sustainable use of ecosystems. (C) 2013 Elsevier B.V. All rights reserved.
    https://doi.org/10.1016/j.ecolecon.2013.02.009
  • Aspects of Applied Biology
    2013

    Shifts in functional plant groups in ditch banks under agri-environment schemes and in nature

    W. F. A. van Dijk, A. P. Schaffers, Jasper van Ruijven, Frank Berendse, Geert de Snoo
    Management of ditch banks of agricultural fields is considered to be a promising and multifunctional application of agri-environment schemes (AES) on farmland. Our previous research has shown that in the Netherlands, there is a small increase in the number of target plant species of AES in ditch banks. However, the productivity and Ellenberg indicator value for nitrogen also increased. This suggests a change in species composition towards more competitive species. This is important, because management mainly focuses on restoring disturbance tolerant species that used to be common in meadows, rather than competitive dominants. In this study we use a large scale dataset of target species composition in ditch banks of nature reserves and ditch banks with and without AES over 10 years to monitor results of functional plant species groups under these different management regimes. Our analyses show that plant functional type composition in ditch banks of agricultural fields indeed shifted towards more competitive species over the last 10 years, independent of AES. In nature reserves, a similar increase in competitive species was observed. The shift towards more competitive species was reflected in the increase of the average height of the vegetation and the increase in species with a leafy canopy structure, whereas species with a semi-basal canopy structure were decreasing. We conclude that current AES does not increase the number of targeted disturbance tolerant species and that more disturbance such as more frequent mowing is required to obtain these species.
  • Communications in agricultural and applied biological sciences
    2012

    Linking land use with pesticides in Dutch surface waters

    Maarten van't Zelfde, Will Tamis, Martina G. Vijver, Geert de Snoo

    Compared with other European countries The Netherlands has a relatively high level of pesticide consumption, particularly in agriculture. Many of the compounds concerned end up in surface waters. Surface water quality is routinely monitored and numerous pesticides are found to be present in high concentrations, with various standards being regularly exceeded. Many standards-breaching pesticides exhibit regional patterns that can be traced back to land use. These patterns have been statistically analysed by correlating surface area per land use category with standards exceedance per pesticide, thereby identifying numerous significant correlations with respect to breaches of both the ecotoxicological standard (Maximum Tolerable Risk, MTR) and the drinking water standard. In the case of the MTR, greenhouse horticulture, floriculture and bulb-growing have the highest number as well as percentage of standard-breaching pesticides, despite these market segments being relatively small in terms of area cropped. Cereals, onions, vegetables, perennial border plants and pulses are also associated with many pesticides that exceed the drinking water standard. When a correction is made for cropped acreage, cereals and potatoes also prove to be a major contributor to monitoring sites where the MTR standard is exceeded. Over the period 1998-2006 the land-use categories with the most and highest percentage of standards-exceeding pesticides (greenhouse horticulture, bulb-growing and flower cultivation) showed an increase in the percentage of standards-exceeding compounds.

  • Environmental Toxicology and Chemistry
    2012

    Multimetal accumulation in crustaceans in surface water related to body size and water chemistry

    Anja J. Verschoor, A.J. Hendriks, J. P. M. Vink, Geert de Snoo, Martina G. Vijver
    Many relationships of bioaccumulation of metals have been derived in the past, but verification in the field is often lacking. In the present study, the authors collected field data on bioaccumulation in caged Daphnia magna and Gammarus roeseli in 12 different contaminated brooks. Besides generating a comprehensive data set on bioaccumulation for these species, the authors also checked whether the bioavailability at the biotic ligand is useful to explain differences in observed bioaccumulation. Increasing bioaccumulation of Mn, Cd, Co, and Ni was observed, which leveled off at higher concentrations. Whole-body concentrations of Ca, Na, Mg, K, Fe, Cu, Se, and Zn were independent of exposure concentrations. Univariate and multivariate regressions were performed to examine the relationships between accumulated metals and dissolved metal concentrations (Cw), fractional occupancy of the biotic ligand (fBL), species weight, and other undefined species traits. Significant relations between body weight and bioaccumulation were found for Na, Fe, Mn, Cd, Co, and Zn; smaller organisms accumulated larger amounts of these elements. Reduced body weight was accompanied by elevated concentrations of Co, Cu, and Fe in D. magna and elevated concentrations of Mn in G. roeseli, indicating toxicity. Although significant relations were found between bioaccumulation and fBL for Mn and Co, Cw was a better predictor of bioaccumulation. Environ. Toxicol. Chem. 2012; 31: 22692280. (c) 2012 SETAC
    https://doi.org/10.1002/etc.1941
  • Diversity and Distributions
    2012

    Simulating climate change impacts on forests and associated vascular epiphytes in a subtropical island of East Asia

    R. C. C. Hsu, Will Tamis, N. Raes, Geert de Snoo, Jan H. D. Wolf, G. Oostermeijer, S. H. Lin
    Aim This study aims to assess the impact of climate change on forests and vascular epiphytes, using species distribution models (SDMs). Location Island of Taiwan, subtropical East Asia. Methods A hierarchical modelling approach incorporating forest migration velocity and forest type-epiphyte interactions with classical SDMs was used to model the responses of eight forest types and 237 vascular epiphytes for the year 2100 under two climate change scenarios. Forest distributions were modelled and modified by dominant tree species' dispersal limitations and hypothesized persistence under unfavourable climate conditions (20 years for broad-leaved trees and 50 years for conifers). The modelled forest projections together with 16 environmental variables were used as predictors in models of epiphyte distributions. A null method was applied to validate the significance of epiphyte SDMs, and potential vulnerable species were identified by calculating range turnover rates. Results For the year 2100, the model predicted a reduction in the range of most forest types, especially for Picea and cypress forests, which shifted to altitudes c. 400 and 300 m higher, respectively. The models indicated that epiphyte distributions are highly correlated with forest types, and the majority (77-78%) of epiphyte species were also projected to lose 45-58% of their current range, shifting on average to altitudes c. 400 m higher than currently. Range turnover rates suggested that insensitive epiphytes were generally lowland or widespread species, whereas sensitive species were more geographically restricted, showing a higher correlation with temperature-related factors in their distributions. Main conclusions The hierarchical modelling approach successfully produced interpretable results, suggesting the importance of considering biotic interactions and the inclusion of terrain-related factors when developing SDMs for dependant species at a local scale. Long-term monitoring of potentially vulnerable sites is advised, especially of those sites that fall outside current conservation reserves where additional human disturbance is likely to exacerbate the effect of climate change.
    https://doi.org/10.1111/j.1472-4642.2011.00819.x
  • Applied Vegetation Science
    2012

    Long-term changes in plant diversity of grasslands under agricultural and conservation management

    Geert de Snoo, N.C. Naus, Jort Verhulst, Jasper van Ruijven, A. P. Schaffers
    Question In many industrialized countries biodiversity is declining. Although changes in species composition and species richness have been documented for many individual systems, little long-term research has been done on a regional scale. We compared the temporal patterns of plant diversity over the last 30 yr in agricultural grasslands and nature reserves. Location Grasslands scattered over the entire province of South-Holland, the Netherlands. Methods Using data from 403 permanent plots over a period of 30 yr, we analysed temporal trends in species richness, floristic value and indicated nutrient richness and compared these trends between agricultural grasslands and grasslands in nature reserves. Results Expressed as 30-yr averages, species richness and floristic value were much higher in nature reserve grasslands than in agricultural grasslands (an increase of 87% and 78%, respectively), while indicated nutrient richness (determined using indicator values for soil fertility of the species present) was 31% lower. During this 30-yr period, species richness and floristic value significantly increased in nature reserve grasslands (0.186 species.yr-1). For agricultural grasslands, however, no significant changes could be detected. Restricting the analysis to those plots that were already studied before 1990 did reveal significant declines in the agricultural grasslands, indicating a past decrease in species richness that has probably levelled off after 1990. Conclusions These findings imply that the floristic gap between agricultural grasslands and grasslands in nature reserves is widening every year. This may have consequences for conservation efforts in both nature reserves and agricultural grasslands. The challenge is to enhance the interaction between nature reserves and agricultural grasslands.
    https://doi.org/10.1111/j.1654-109X.2011.01181.x
  • Biological Conservation
    2012

    Response of ground-nesting farmland birds to agricultural intensification across Europe: Landscape and field level management factors

    Irene Guerrero, Manuel B. Morales, Juan J. Oñate, Flavia Geiger, Frank Berendse, Geert de Snoo, Sönke Eggers, Tomas Pärt, Jan Bengtsson, Lars W. Clement, Wolfgang W. Weisser, Adam Olszewski, Piotr Ceryngier, Violetta Hawro, Jaan Liira, Tsipe Aavik, Christina Fischer, Andreas Flohre, Carsten Thies, Teja Tscharntke
    European farmland bird populations have decreased dramatically in recent decades and agricultural intensification has been identified as the main cause contributing to these declines. Identifying which specific intensification pressures are driving those population trends seems vital for bird conservation in European farmland. We investigated the response of ground-nesting farmland birds to the multivariate process of agricultural intensification in six European countries covering a bio-geographical and intensification gradient. Supported by PCA analysis, two groups of factors, related to field management and landscape modification, were considered, seeking to discriminate the relative importance of the effects of these main intensification components. Variance partition analysis showed that landscape factors accounted for most of the variation of ground-nesting farmland bird individual and breeding pair densities, as well as Skylark (i.e. our single model species) individual densities. In the case of Skylark breeders, field factors were found to be more important to explain their density. Our results suggest that in general farmland bird densities as well as Skylark densities are higher in simple landscapes dominated by agriculture, but with smaller fields and more different crops on the farms. In addition, high yields were negatively related to bird densities. We conclude that while management actions aimed at farmland bird conservation taken at landscape level may exert a strong positive effect on overall bird densities, those taken at field level are also relevant, particularly for breeders and, therefore, may potentially influence the persistence of these species’ populations.
    https://doi.org/10.1016/j.biocon.2012.04.001
  • International Journal of Life Cycle Assessment
    2012

    Life cycle assessment of aquaculture systems-a review of methodologies

    P. J. G. Henriksson, J. B. Guinee, R. Kleijn, Geert de Snoo
    Purpose As capture fishery production has reached its limits and global demand for aquatic products is still increasing, aquaculture has become the world's fastest growing animal production sector. In attempts to evaluate the environmental consequences of this rapid expansion, life cycle assessment (LCA) has become a frequently used method. The present review of current peer-reviewed literature focusing on LCA of aquaculture systems is intended to clarify the methodological choices made, identify possible data gaps, and provide recommendations for future development within this field of research. The results of this review will also serve as a start-up activity of the EU FP7 SEAT (Sustaining Ethical Aquaculture Trade) project, which aims to perform several LCA studies on aquaculture systems in Asia over the next few years. Methods From a full analysis of methodology in LCA, six phases were identified to differ the most amongst ten peer-reviewed articles and two PhD theses (functional unit, system boundaries, data and data quality, allocation, impact assessment methods, interpretation methods). Each phase is discussed with regards to differences amongst the studies, current LCA literature followed by recommendations where appropriate. The conclusions and recommendations section reflects on aquaculture-specific scenarios as well as on some more general issues in LCA. Results Aquaculture LCAs often require large system boundaries, including fisheries, agriculture, and livestock production systems from around the globe. The reviewed studies offered limited coverage of production in developing countries, low-intensity farming practices, and non-finfish species, although most farmed aquatic products originate from a wide range of farming practices in Asia. Apart from different choices of functional unit, system boundaries and impact assessment methods, the studies also differed in their choice of allocation factors and data sourcing. Interpretation of results also differed amongst the studies, and a number of methodological choices were identified influencing the outcomes. Conclusions and recommendations Efforts should be made to increase transparency to allow the results to be reproduced, and to construct aquaculture related database(s). More extensive data reporting, including environmental flows, within the greater field of LCA could be achieved, without compromising the focus of studies, by providing supporting information to articles and/ or reporting only ID numbers from background databases. More research is needed into aquaculture in Asia based on the latest progress made by the LCA community.
    https://doi.org/10.1007/s11367-011-0369-4
  • Sustainability
    2012

    Institutions and Ecosystem-Based Development Potentials of the Elephant Marsh, Malawi

    I. B. M. Kosamu, W.T. de Groot, P. S. Kambewa, Geert de Snoo
    The Elephant Marsh, a wetland in Southern Malawi, is important for fishing, agriculture, hunting and the collection of natural resources for the livelihoods of local communities. However, there has been increasing pressure driven by a changing climate, population growth, rural poverty and agricultural conversion, all of which threaten the future of the wetland. Currently, Malawi does not have either a national wetland policy or a climate change policy and wetland issues are only marginally present in the National Parks and Wildlife Policy of 2000 and National Fisheries and Aquaculture Policy of 2001. As a result, the country lacks a framework that could be strong enough to achieve balanced and sustainable wetland management for multiple resource users. The objective of this study was to establish the development potentials of Elephant Marsh from an ecosystem-based ('working-with-nature') perspective. It was revealed that there are development potentials in fisheries, recession agriculture, biomass for energy, conservation and tourism. This paper emphasizes that as these opportunities are developed, there will be the need to strengthen management institutions at local and national levels, and the coordination between the two.
    https://doi.org/10.3390/su4123326
  • Renewable & Sustainable Energy Reviews
    2012

    LCA of second generation bioethanol: A review and some issues to be resolved for good LCA practice

    E. I. Wiloso, R. Heijungs, Geert de Snoo
    This paper aims at reviewing the life cycle assessment (LCA) literature on second generation bioethanol based on lignocellulosic biomass and at identifying issues to be resolved for good LCA practice. Reviews are carried out on respective LCA studies published over the last six years. We use the classification of lignocellulosic biomass to define system boundaries, so that the comparison among LCA results can be thoroughly assessed based on identified system components. A basis for attributing environmental burden for different biomass feedstocks is also suggested. Despite the non-homogeneous systems, we conclude that second generation bioethanol performs better than fossil fuel at least for the two most studied impact categories, net energy output and global warming. For the latter category, carbon sequestration at the biomass generation stage can even consistently offset the GHG emissions from all parts of the life cycle chains at high ethanol percentage ( >= 85%). The aspect of biogenic carbon and agrochemical input for energy crops and biomass residues, and the effect of removal of the latter from soil have not been treated consistently. In contrast, the exclusion of upstream chain of biomass waste feedstocks is observed in practice. The bioethanol conversion process is mostly based on simultaneous saccharification and co-fermentation, characterized by high yield and low energy input. In this regard, the LCA results tend to under estimate the real impacts of the current technology. The choice of allocation methods strongly influences the final results, particularly when economic value is used as a reference. Substitution of avoided burden seems to be the most popular allocation method in practice, followed by partition based on mass, energy, and economic values. (C) 2012 Elsevier Ltd. All rights reserved.
    https://doi.org/10.1016/j.rser.2012.04.035
  • Ibis
    2012

    Interspecific and intraspecific differences in habitat use and their conservation implications for Palaearctic harriers on Sahelian wintering grounds

    R. Buij, D. Van der Goes, Hans H. de Iongh, S. Gagare, P. Haccou, J. Komdeur, Geert de Snoo
    The floodplains of the West-African Sahel region have experienced extensive habitat transformation during the past four decades, coinciding with an impoverishment of raptor populations. We investigated foraging patterns of Palaearctic migratory Eurasian Marsh Harriers Circus aeruginosus, Pallid Harriers C.macrourus and Montagus Harriers C.pygargus on a floodplain system in northern Cameroon to assess species, sex- and age-related habitat preferences. Sex and age have rarely been incorporated into general studies of raptor habitat associations, despite clear evidence of intrasexual and age-related differences in foraging strategies and diet composition, potentially carrying strong conservation implications. We found evidence of sexual differences in foraging preference related to land use, particularly in the most sexually dimorphic Pallid Harrier, and evidence that juveniles used different habitats to adults. This constitutes the first quantitative documentation of such differentiation by Palaearctic raptors on African wintering grounds, indicating that general patterns of habitat use in wintering raptors may obscure sex- and age-specific preferences. Contrary to expectations, we found limited evidence for interspecific foraging segregation. Food partitioning by prey mass was related to harrier body mass and facilitated by a diverse availability of prey on human-transformed floodplains. Anticipated further large-scale conversion of floodplain habitat into predominantly desiccated grasslands raises concerns about the survival of wintering harriers.
    https://doi.org/10.1111/j.1474-919X.2011.01200.x
  • Bird Conservation International
    03-2011

    Abundance of invertebrate prey for birds on organic and conventional arable farms in the Netherlands

    S. Kragten, Will Tamis, E. Gertenaar, S. M. Midcap Ramiro, R. J. van der Poll, J. Wang, Geert de Snoo
    https://doi.org/10.1017/S0959270910000079
  • Journal for Nature Conservation
    2011

    Effects of mowing date on the opportunities of seed dispersal of ditch bank plant species under different management regimes

    X. Leng, C.J.M. Musters, Geert de Snoo
    Mowing and plant removal is a traditional practice in low-intensity farming and likely to lead to high plant species richness. Even today, scientific knowledge on the impact of mowing on seed availability is still very limited. We studied whether the seed availability of ditch bank plant species was affected by the timing of mowing and, if so, whether the effect varied according to management regime (nature reserve, agri-environment scheme (AES) with long-term management, AES with short-term management, conventional management). Our focus was on seed availability for transportation, because restoration of ditch bank vegetation is known to be limited by seed dispersal. The presence and seed-setting of 25 target species in 384 plots were recorded at the mowing date, under four management regimes. A Hierarchical Generalised Linear Model (HGLM) was used to analyse the effects of mowing date and management on the number of species setting seed. It suggests that when the mowing is twice annually, mowing on July 1st and on September 1st will result in a maximum number of species of which the seeds are available for transportation and, therefore, create largest opportunities for seed dispersal on ditch banks in the western peat area of the Netherlands. The effect of mowing date differs among species, with certain rare species like Caltha palustris and Lythrum salicaria in particular differing from the commoner species. A flexible mowing regime varying from year to year would therefore help to protect these rare species. The later peak in seed-setting found in nature reserves and long-term AES suggest a postponed mowing compared to conventionally management and short-term AES. (C) 2010 Elsevier GmbH. All rights reserved.
    https://doi.org/10.1016/j.jnc.2010.11.003
  • Oryx
    2011

    Human-carnivore conflict around Pendjari Biosphere Reserve, northern Benin

    E. A. Sogbohossou, Hans H. de Iongh, B. Sinsin, Geert de Snoo, P. J. Funston
    Close proximity between humans and large predators results in high levels of conflict. We investigated the extent of, and factors leading to, this conflict through focal group and individual interviews in all villages around Pendjari Biosphere Reserve, northern Benin. Livestock losses from 2000 to 2007 (n = 752) were reported to be mainly caused by spotted hyaena Crocuta crocuta (53.6%), baboon Papio anubis (24.8%), and lion Panthera leo (18.0%). These predators mainly predated sheep and goats (52.1%) and pigs (42.3%), with lions being the main predators of cattle (78.9%). Lion and hyaena diets were more diverse than that of baboons, which killed only small stock. The level of conflict increased during 2000-2007. Predation rate differs between predator species and is significantly influenced by month, rainfall of the month before the predation event, and length of the dry period in a year. The geographical position of the village, the distance of the village to the Park and the number of herbivores legally killed every hunting season also influenced predation intensity. Our findings suggest that improvement of husbandry techniques and education will reduce conflicts and contribute to improved conservation of these threatened predators.
    https://doi.org/10.1017/s0030605310001109
  • Communications in agricultural and applied biological sciences
    2011

    Contribution by neighbouring countries to pesticides in the Dutch surface waters

    Maarten van't Zelfde, Will Tamis, Martina G. Vijver, Geert de Snoo
  • Plant Ecology
    2011

    Vegetation development in sown field margins and on adjacent ditch banks

    J. Noordijk, C.J.M. Musters, Jerry van Dijk, Geert de Snoo
    The creation of temporal and newly sown field margins for 6 years is a common agri-environment scheme (AES) in the Netherlands. Conservation profits resulting from AES vary over different areas and need further studying. We examined plant species richness in such field margins and adjacent ditch banks in the province of Zeeland, where these linear elements do not experience plant biomass removal after mowing as management strategy. First, during 2 years, we inventoried field margins sown with a wildflower mixture and related the species composition and richness to the age of the margins. In a second assessment, we studied plant species richness on ditch banks protected from arable fields by these margins. Major clusters in a principal component analysis (PCA) on species composition in the field margins showed a succession from sown and ruderal annual species (year 1), to sown perennial species (year 2) and ending with a dominance by tussock forming grass species and Urtica dioica (year 5-6). Total plant species richness decreased with increasing age of the margins, and this was caused by the combination of a decline in sown species and a stable number of not-sown species. The presence of field margins during several years did not result in an increase in plant species richness on adjacent ditch banks. In both the field margins and on the ditch banks, mowing management is not followed by the removal of the cuttings. For plant conservation, the results of these field margins are disappointing, probably due to the lack of a proper management. Therefore, we recommend implementing a hay-making and opening management, to increase plant richness and to reduce noxious weeds in the margins and on the ditch banks.
    https://doi.org/10.1007/s11258-010-9811-0
  • Applied Psychology-an International Review-Psychologie Appliquee-Revue Internationale
    2011

    What's in it for Me? Motivational Differences between Farmers' Subsidised and Non-Subsidised Conservation Practices

    A. M. Lokhorst, H. Staats, Jerry van Dijk, Eric van Dijk, Geert de Snoo
    Through nature conservation practices, farmers can strongly enhance nature quality and biodiversity in rural areas. In this paper, the social psychological underpinnings of farmers' nature conservation practices are investigated using the Theory of Planned Behavior, to which the concepts of self-identity and personal norms were added. A distinction is made between nature conservation practices done on a non-subsidised basis and nature conservation practices for which farmers receive some form of remuneration from the Dutch government. Eighty-five arable farmers participated in our survey. Results show that our model explains more variance in the intention to perform non-subsidised than subsidised nature conservation practices. Also, the concepts of self-identity and personal norms appear to be related to the intention to perform non-subsidised, not subsidised conservation.
    https://doi.org/10.1111/j.1464-0597.2011.00438.x
  • Environmental Toxicology and Chemistry
    2011

    Response predictions for organisms water-exposed to metal mixtures: a meta-analysis

    Martina G. Vijver, E. G. Elliott, Wjgm Peijnenburg, Geert de Snoo
    To develop a multimetal toxicity model requires insight into the relationships between the composition of metal mixtures and their toxicological effects on organisms. As a first step in developing such a model, quantitative data from binary and higher mixture studies of Cu, Cd, and Zn were compiled and used to assess trends in toxicological effects on various organisms. The findings of this meta-analysis show relatively little occurrence of additive effects compared with antagonistic and synergistic effects. This observation held true irrespective of test species, environmental compartment, or metal concentrations in the mixture. However, the type of effect was significantly correlated with the metal combination tested and the selected toxicological endpoint. It was also found that different methods were used for assessing deviation from additivity in the various individual studies. For robust comparison, standardization on this point is required. Toxicological responses of organisms to metal mixtures were shown to be hard to predict and were often slightly less than or slightly more than additive. The interactions observed could not be explained by metal metal interactions alone. We therefore conclude that with current scientific knowledge it is not yet possible to predict responses to metal mixtures in individual cases; at best this is possible only in terms of general patterns. Nevertheless, in the context of environmental risk policy, the assumption of additivity produces a conservative prediction of toxicity, because toxicity of a metal mixture will be either predicted correctly or overpredicted by default in approximately 75% of all cases. The use of models based on noninteraction is satisfactory from this regulatory perspective. Environ. Toxicol. Chem. 2011;30:1482-1487. (C) 2011 SETAC
    https://doi.org/10.1002/etc.499
  • Environmental Science and Technology
    2011

    Spatial and Temporal Variation of Watertype-Specific No-Effect Concentrations and Risks of Cu, Ni, and Zn

    Anja J. Verschoor, J. P. M. Vink, Geert de Snoo, Martina G. Vijver
    Geographical and temporal variations in metal speciation were calculated and water-type specific sensitivities were derived for a range of aquatic species, using surveillance water chemistry data that cover almost all surface water types in The Netherlands. Biotic ligand models for Cu, Zn, and Ni were used to normalize chronic no-effect concentrations (NOEC) determined in test media toward site-specific NOEC for 372 sites sampled repeatedly over 2007-2010. Site-specific species sensitivity distributions were constructed accounting for chemical speciation. Sensitivity of species as well as predicted risks shifted among species over space and time, due to changes in metal concentrations, speciation, and biotic ligand binding. Sensitivity of individual species (NOEC) and of the ecosystem (HC5) for Cu, Ni, and Zn showed a spatial variation up to 2 orders of magnitude. Seasonality of risks was shown, with an average ratio between lowest and highest risk of 1.3, 2.0, and 3.6 for Cu, Ni, and Zn, respectively. Maximum risks of Cu, Ni, and Zn to ecosystems were predicted in February and minimum risks in September. A risk assessment using space-time specific HC5 of Cu and Zn resulted in a reduction of sites at risk, whereas for Ni the number of sites at risks increased.
    https://doi.org/10.1021/es2007963
  • Environmental Science and Technology
    2011

    Smart Nanotoxicity Testing for Biodiversity Conservation

    L. Song, Martina G. Vijver, Wjgm Peijnenburg, Geert de Snoo
    https://doi.org/10.1021/es202094w
  • Journal of Ornithology
    2011

    Effectiveness of spatial mosaic management for grassland breeding shorebirds

    E. B. Oosterveld, F. Nijland, C.J.M. Musters, Geert de Snoo
    Since 2000, a new management technique has been introduced to stop the rapid decline of grassland breeding shorebirds in the Netherlands, called 'mosaic management'. The most important difference from earlier Agri-Environment Schemes is that the mosaic management is conducted at a landscape scale (150-650 ha) rather than an individual farm scale (50-60 ha) and that there is purposeful planning of the spatial distribution and layout of management measures within a local area. We tested the effectiveness of the mosaic management by analysing breeding population trends of Northern Lapwing (Vanellus vanellus), Black-tailed Godwit (Limosa limosa), Redshank (Tringa totanus) and Oystercatcher (Haematopus ostralegus) in comparison with three other management types: individual management, regular farmland and nature reserves. After the introduction of mosaic management, populations of Black-tailed Godwit and Redshank stabilised and Northern Lapwing populations increased. Oystercatcher decreased, but this was also due to reduced winter survival. Populations in the mosaic management areas showed a greater annual improvement of 0-18% compared to other management types. The mosaic areas did not appear to be 'sink' areas as productivity in the mosaic areas seemed to be sufficient to support the observed densities. However, with the exception of Northern Lapwing, the change of trend was not greater in the mosaic areas than in the other management types. So, for the species other than Northern Lapwing, the good performance cannot be attributed to the mosaic management. The mosaic areas were good breeding habitats beforehand and continue to be so. It is possible that the mosaic management is part of the success, but not exclusively so. Our results show that modern farming can still be combined with grassland breeding shorebird management. However, further study of success factors is urgently needed for the conservation of the remaining good habitats on farmland and restoration of lost ones.
    https://doi.org/10.1007/s10336-010-0561-5
  • Basic and Applied Ecology
    2011

    Spatiotemporal variation of plant diversity on ditch banks under different management regimes

    X. Leng, C.J.M. Musters, Geert de Snoo
    Agricultural intensification has led to a loss of biological diversity at various spatial and temporal scales and understanding the mechanisms driving these changes would help target conservation efforts accordingly. In this study we used additive partitioning of diversity and the Jaccard index of similarity to estimate the spatial and temporal patterns of plant diversity on ditch banks under different management regimes (nature reserves and agricultural areas). We focused on a total of 118 species, including 18 indicator species of conservation interest, at 42 sites in three successive sampling periods. For all species taken together, beta diversity contributed most to total observed species diversity, but was less than expected under random distribution. Indicator species showed greater beta diversity on a spatial scale compared to all species, but much less so on a temporal scale. Importantly, the differences in indicator species composition on a spatial scale are probably due to environmental heterogeneity and dispersal limitation, indicating that management strategies should focus on both factors. Nature reserves showed higher alpha diversity within sites because of possible lower nutrient inputs and grazing intensity compared with agricultural areas, while both exhibited scale-dependent dispersal limitation.
    https://doi.org/10.1016/j.baae.2010.10.005
  • Conservation Genetics
    2011

    No evident spatial genetic structuring in the rapidly declining Black-tailed Godwit Limosa limosa limosa in The Netherlands

    K. B. Trimbos, C.J.M. Musters, Y. I. Verkuil, Rosemarie Kentie, Theunis Piersma, Geert de Snoo
    With 40% of the European Black-tailed Godwit population breeding in The Netherlands, this country harbours internationally significant numbers of this species. However, ongoing agricultural intensification has resulted in the fragmentation of the population and drastic population declines since 1967. By establishing genetic diversity, genetic differentiation and gene flow on the basis of 12 microsatellites, we investigated whether the population genetic structure of the Dutch Black-tailed Godwit bears the marks of these changes. Genetic diversity appeared to be moderate, and Bayesian model-based analysis of individual genotypes revealed no clustering in the Dutch populations. This was supported by pairwise F-ST values and AMOVA, which indicated no differentiation among the nine breeding areas. Gene flow estimates were larger than "one migrant per generation" between sample locations, and no isolation by distance was demonstrated. Our results indicate the maintenance of moderate levels of genetic diversity and genetic connectivity between breeding sites throughout the Dutch Black-tailed Godwit breeding population. We suggest that the Dutch Black-tailed Godwit breeding areas should be managed as a single panmictic unit, much as it is presently done.
    https://doi.org/10.1007/s10592-010-0167-8
  • Communications in agricultural and applied biological sciences
    2011

    Similarities and differences between measured and predicted concentrations of pesticides in Dutch surface waters

    Martina G. Vijver, R. Kruijne, Maarten van't Zelfde, A.M. van der Linden, Will Tamis, Geert de Snoo
  • Biodiversity and Conservation
    2010

    Invertebrates in field margins: taxonomic group diversity and functional group abundance in relation to age

    J. Noordijk, C.J.M. Musters, Jerry van Dijk, Geert de Snoo
    Sown, temporary field margins are a common agri-environment scheme (AES) in the Netherlands. Despite their wide application, though, there has been scarcely any long-term monitoring of the succession of invertebrates. In the field margins of 40 farms, invertebrate diversity and the abundance of three functional groups were assessed in relation to age. The diversity in terms of number of species groups was found to increase with the age of the margins. The abundance of herbivores and detritivores also showed a positive correlation with the age of the margins. However, the abundance of predators decreased with increasing age. Older margins showed a higher total vegetation cover and fewer plant species, also resulting in lower plant species evenness. We suggest several changes to the current AES regulations. For the conservation of invertebrate diversity, longer-lasting field margins are desirable. In addition, old margins are favoured by detritivores, a group that has particular difficulty finding suitable habitats in agricultural landscapes. However, such margins are less favourable from an agricultural perspective, as they appear unsuitable for high abundances of potentially useful predators and the high vegetation cover attracts many potentially harmful herbivores. To circumvent this, the AES might be extended by incorporating hay-making, which would reduce standing biomass and might lead to more predators and fewer herbivores.
    https://doi.org/10.1007/s10531-010-9890-1
  • Agriculture, Ecosystems and Environment
    2010

    Landscape composition influences farm management effects on farmland birds in winter: A pan-European approach

    Flavia Geiger, Geert de Snoo, Frank Berendse, Irene Guerrero, Manuel B. Morales, J. J. Onate, Sönke Eggers, Tomas Pärt, Riccardo Bommarco, Jan Bengtsson, Lars W. Clement, Wolfgang W. Weisser, Adam Olszewski, Piotr Ceryngier, Violetta Hawro, P. Inchausti, Christina Fischer, Andreas Flohre, Carsten Thies, Teja Tscharntke
    This study examined the effects of agricultural intensity, various farming practices, landscape composition and vegetation cover on the abundance and species richness of wintering farmland birds, assessed simultaneously across seven European regions. The abundance and species richness of wintering farmland birds were negatively affected by agricultural intensity. The effects of yield and farm type were interlinked. Of the 10 farming practices assessed, mechanical weeding and the amount of organic fertilizer applied negatively affected farmland birds, presumably due to reduced food availability on arable fields. Positive effects of organic farming on farmland birds proved to be limited to simplified landscapes. More farmland birds were observed in areas with more stubble, pasture and green manure crops. Species richness was higher in areas with more pasture. The results of this study show that farm management, vegetation cover and landscape composition all influence wintering farmland birds. Heterogeneous landscapes comprising arable crops as well as grasslands support most species of farmland birds in winter. The effectiveness of organic farming and agri-environment schemes depends on landscape composition. Therefore, different agri-environment schemes should be designed for different landscape types. (c) 2010 Elsevier B.V. All rights reserved.
    https://doi.org/10.1016/j.agee.2010.09.018
  • Biological Conservation
    2010

    Synergy between nature reserves and agri-environmental schemes in enhancing ditch bank target species plant diversity

    X. Leng, C.J.M. Musters, Geert de Snoo
    The issue of what conservation strategies to apply in agricultural landscape for the most effective protection of biodiversity has been debated for some years. The creation and maintenance of nature reserves is often hampered by both ecological and economic factors, while the ecological effectiveness of agri-environment schemes (AES) is still being queried. Our study examined how the spatial pattern of nature reserves and AES affects the diversity of 25 target species of conservation interest in ditch banks and how this information might be used to develop a strategy resulting in synergy between protected areas and enhanced matrix quality. We studied target species plant diversity on 92 ditch banks under AES and on 102 banks not under such a regime; all of them running parallel to nature reserves. We compared the results with those obtained from a previous study which focused on ditch banks running transverse. On non-AES ditch banks running parallel to nature reserves, there was a significant decline in species richness with increasing distance from the nature reserve while this was not the case for AES ditch banks. The effect of AES differed between the two directions, with a significant effect beyond 200 m in the parallel direction and within 200 m in the transverse direction. Our results indicate that synergy between nature reserves and AES can enhance plant diversity and, since the AES effect was different in different direction due to wind direction and nitrogen input to adjacent fields, location of AES should be chosen carefully. (C) 2010 Elsevier Ltd. All rights reserved.
    https://doi.org/10.1016/j.biocon.2010.03.023
  • Human Ecology
    2010

    Using Tailored Information and Public Commitment to Improve the Environmental Quality of Farm Lands: An Example from the Netherlands

    A. M. Lokhorst, Jerry van Dijk, H. Staats, Eric van Dijk, Geert de Snoo
    By adopting nature conservation practices, farmers can enhance the environmental quality and biodiversity of their land. In this exploratory study, a behavioral intervention that focused on improving Dutch farmers' nature conservation practices was developed and tested. This intervention was based on insights derived from social psychology and combined tailored information and public commitment. Participating farmers were divided in three groups: one group received tailored information only, one group received both tailored information and a public commitment manipulation, and one group served as a control. A questionnaire measuring relevant aspects of conservation was completed before and after the intervention. Results show that tailored information combined with public commitment making resulted in a stronger desire to engage in conservation, an increase in surface area of non-subsidized natural habitat, and an increase in time farmers spent on conservation. The intervention affected both subsidized and non-subsidized conservation, but the effects were stronger for non-subsidized conservation.
    https://doi.org/10.1007/s10745-009-9282-x
  • Ardea
    2010

    Timing of the breeding season of Black-tailed Godwit Limosa limosa and Northern Lapwing Vanellus vanellus in The Netherlands

    C.J.M. Musters, W. J. ter Keurs, Geert de Snoo
    Long-distance migratory bird species might face larger problems to adapt to local climate change in their breeding area than short-distance migrants. This study investigated the effect of climatic change on the timing of the breeding season of two wader species with contrasting migration strategies, the long-distance migratory Black-tailed Godwit Limosa limosa and the short-distance migrant Northern Lapwing Vanellus vanellus. We tested the hypothesis that a change in breeding schedule will be stronger in the Lapwing than in the Godwit. Our analyses are based on the ringing dates of around 35,000 Black-tailed Godwit chicks and 112,000 Lapwing chicks from 1960 to 2004 in The Netherlands. The results demonstrate that the Lapwing is breeding earlier than in the 1960s, independent of the species' direct response to warm early springs. In contrast, the Godwit does not exhibit earlier breeding dates other than a direct response to warmer springs. Our observations suggest that the Godwit is not able to advance breeding dates to cope with changes in its breeding habitat. This could mean the species is suffering lower breeding success than would have been the case if it had adapted, and this could be one of the reasons for the stronger decline in The Netherlands of the Godwit population than that of the Lapwing.
    https://doi.org/10.5253/078.098.0209
  • Environmental Science and Technology
    2010

    Toxicological Mixture Models are Based on Inadequate Assumptions

    Martina G. Vijver, Wjgm Peijnenburg, Geert de Snoo
    https://doi.org/10.1021/es1001659
  • Journal of Vegetation Science
    2010

    Spatial variation in ditch bank plant species composition at the regional level: the role of environment and dispersal

    X. Leng, C.J.M. Musters, Geert de Snoo
    Questions Can patterns of species similarity on ditch banks be explained by environmental and dispersal factors and, if so, to what extent? Does the pattern of distance decay differ among different species groups (all species versus target species of conservation interest; species of different dispersal type)? Location Krimpenerwaard, the Netherlands. Methods In 2006-2007, ditch bank vegetation data on 130 terrestrial herbaceous species were collected on 72 plots. Species similarity was measured and related to environmental distance (soil type and nutrient level) and dispersal distance (geographic distance and limitation of dispersal by water, wind and agricultural activities) as explanatory factors using multiple regression on distance matrices (MRM). Differences in rates of distance decay in species similarity among different subsets of data (species groups) were investigated using randomization tests. Results In all species, patterns of similarity of composition are influenced mainly by variations in dispersal, while for target species these are due to combined effects of environmental and dispersal variation. Compared with species using other dispersal mechanisms, water-dispersed species had half the rate of distance decay. Conclusions For all species considered here, dispersal limitation seems more responsible for the spatial variation in species composition than environmental determinism. Conservation management focused on plant species diversity would be more successful in areas adjacent to those where a similar management regime is already in force. For target species of conservation interest, besides dispersal limitation, environmental determinants like nutrient level are also important. As a means of conserving such target species, therefore, focusing on reducing nutrient levels and facilitating species dispersal will be more effective than current management practices, which mainly focus on reducing fertilizer inputs.
    https://doi.org/10.1111/j.1654-1103.2010.01190.x
  • Aspects of Applied Biology
    2010

    An internet-accessible tool for drawing up tailor made management plns for meadow birds

    Th. C.P. Melman, Alex Schotman, B. Vanmeulebroek, M. Kiers, H. Meeuwsen, O. Roosenschoon, Geert de Snoo
  • Entomologische Berichten
    2010

    Insect abundance in cow dung pats of different farming systems

    Flavia Geiger, S.C.T.M. van der Lubbe, A.M.H. Brunsting, Geert de Snoo
  • Aspects of Applied Biology
    2010

    Benchmarking biodiversity performances of farmers

    Geert de Snoo, A. M. Lokhorst, Jerry van Dijk, H. Staats, C.J.M. Musters
  • 2010

    19 - Eco-labelling of agricultural food products

    Helias A. Udo de Haes, Geert de Snoo
    Abstract: This chapter discusses eco-labelling of food products from different types of agriculture, together with the underlying certification systems. Three types of agricultural production are on various points compared with conventional agricultural practice: organic farming, integrated agriculture and regional products. For comparison reasons, three related eco-labelling schemes are added that are relevant for agricultural products: industrial eco-labelling, sustainability certification of natural resources and Fair Trade labelling. Thereafter the effectiveness of the schemes is discussed. The chapter ends with a discussion of some perspectives, particularly of the ever increasing number of labelling schemes.
    https://doi.org/10.1533/9780857090225.4.374
  • Agriculture, Ecosystems and Environment
    2009

    Development of biodiversity in field margins recently taken out of production and adjacent ditch banks in arable areas

    C.J.M. Musters, F.A.N. van Alebeek, Rhem Geers, H Korevaar, A. J. Visser, Geert de Snoo
    Taking field margins out of intensive cultivation is a common form of agri-environmental scheme and on-farm nature management. Typically, no nutrients or pesticides are applied in these margins, which may be sown either with a crop or with grasses and native flowering plants. In some cases the margins are mown, while in others they are left alone. Newly established grass margins are less species-rich than held boundaries or road verges with a long history, justifying the expectation that field margins, if properly managed and given time and appropriate seed sources, could develop into relatively species-rich vegetation. We studied the biodiversity of both margins taken out of production and adjacent ditch banks in the years following initial establishment of the margins. To this end we combined the data of three different projects in order to increase the sensitivity of the statistical analyses. The results showed that the plant species richness of the field margins increased in the years following establishment over a period of four years. In addition, shifts in species composition indicated a decrease in soil nitrate concentrations. The species richness of both butterflies and dragonflies may increase. The most striking result was the marked increase in the plant species richness of the adjacent ditch banks in the five years following creation of the margins. Here, too, changes in species composition indicated a decrease in soil nitrate. in the years following establishment of the field margins there was no increase in the cover of agriculturally harmful weeds in these margins. However, the number of harmful nematodes increased. Our results show the short term effect of establishing field margins. Long term effects are still in need for further research. (C) 2008 Elsevier B.V. All rights reserved.
    https://doi.org/10.1016/j.agee.2008.08.003
  • Land Use Policy
    2009

    Roadmap for interactive exploration of sustainable development opportunities: The use of simple instruments in the complex setting of bottom-up processes in rural areas

    H. J. de Graaf, M. A. W. Noordervliet, C.J.M. Musters, Geert de Snoo
    Before embarking on the development of rural areas or regions it seems necessary to answer the following key questions: what goals of the parties involved can be realized, and where, when and how? To tackle these questions we have developed a 'roadmap', as part of an overall sustainable development procedure for physical planning and spatial management in rural areas. The roadmap is a tool for the process manager and the people involved. It helps to find the way in the exploration of the potential social, economic and ecological benefits of developing the area or region. The purpose of using the roadmap is to alleviate doubts about the advantages of cooperating in pursuit of sustainable development. A back-casting approach is applied to create appealing visions of the future and visualize Mutual opportunities worth implementing. In this article we first describe the need for this new roadmap. We then describe its use, step by step and in some detail. An example of the exploration process is described and the strengths and weaknesses or the roadmap are discussed. (C) 2008 Elsevier Ltd. All rights reserved.
    https://doi.org/10.1016/j.landusepol.2008.03.006
  • Journal of Environmental Management
    2009

    Ecological impacts of early 21st century agricultural change in Europe - A review

    C. Stoate, Andras Baldi, Pedro Beja, Nigel Boatman, Irina Herzon, Pieter A van Doorn, Geert de Snoo, L. Rakosy, C. Ramwell
    The impacts of agricultural land use are far-reaching and extend to areas outside production. This paper provides an overview of the ecological status of agricultural systems across the European Union in the light of recent policy changes. It builds on the previous review of 2001 devoted to the impacts of agricultural intensification in Western Europe. The focus countries are the UK, The Netherlands, Boreal and Baltic countries, Portugal, Hungary and Romania, representing a geographical spread across Europe, but additional reference is made to other countries. Despite many adjustments to agricultural policy, intensification of production in some regions and concurrent abandonment in others remain the major threat to the ecology of agro-ecosystems impairing the state of soil, water and air and reducing biological diversity in agricultural landscapes. The impacts also extend to surrounding terrestrial and aquatic systems through water and aerial contamination and development of agricultural infrastructures (e.g. dams and irrigation channels). Improvements are also documented regionally, such as successful support of farmland species, and improved condition of watercourses and landscapes. This was attributed to agricultural policy targeted at the environment, improved environmental legislation, and new market opportunities. Research into ecosystem services associated with agriculture may provide further pressure to develop policy that is targeted at their continuous provisioning, fostering motivation of land managers to continue to protect and enhance them. Crown Copyright (C) 2009 Published by Elsevier Ltd. All rights reserved.
    https://doi.org/10.1016/j.jenvman.2009.07.005
  • Landschap
    2009

    Boeren over weidevogelbescherming [Farmers' attitudes regarding meadow bird protection]

    J. Noordijk, A. M. Lokhorst, Jerry van Dijk, C.J.M. Musters, H. Staats, Geert de Snoo
  • Landschap
    2009

    Het gaat weer beter met de natuur in Nederland

    Helias A. Udo de Haes, Will Tamis, Geert de Snoo, H.H.T. Prins
  • Basic and Applied Ecology
    2009

    No improvement of plant biodiversity in ditch banks after a decade of agri-environment schemes

    M.M. Blomqvist, Will Tamis, Geert de Snoo
    Restoring plant species richness in intensively farmed areas by means of agri-environment schemes (AES) seems particularly difficult. We studied the effectiveness of a decade of AES in enhancing biodiversity in ditch banks on six modern dairy farms in the Western Peat District in the Netherlands, taking into account the roles of local productivity and of regional diversity and productivity. Biodiversity is characterised as total number of vascular plant species and number of target plant species and productivity as biomass, Ellenberg N-value and grass/forb ratio. We analyzed the repeated AES releves sampled in two periods, 1993-1995 and 2000-2003 and the diversity-productivity relationships in space and over time. For the analysis of the role of the regional factors, repeated AES and reference releves were compared. Number of target species remained stable, whilst the total number of species decreased, and the productivity increased in general in AES ditch banks. We found a clear negative diversity-productivity relationship in space and over time. AES ditch banks showed higher total number of species and comparable to higher number of target species than the reference ditch banks, in general, however, the productivity was also lower in AES ditch banks. The development of AES ditch banks was similar to the regional developments, although differences tended to become smaller in the study period. We hypothesize that the main reason that ditch bank AES do not overall successfully reduce productivity, is because the AES also recommended late mowing and that because of colonization constraints, the region cannot contribute to a positive development. Improvement of AES should, therefore, include adaptation of the mowing regime in high-productivity situations as well as regional strategies to restore the biodiversity of the ditch bank flora. (C) 2008 Gesellschaft fur Okologie. Published by Elsevier GmbH. All rights reserved.
    https://doi.org/10.1016/j.baae.2008.08.007
  • Journal of Cleaner Production
    2009

    Lack of transparency on environmental risks of genetically modified micro-organisms in industrial biotechnology

    Will Tamis, A. van Dommelen, Geert de Snoo
    For the sustainable development of technological innovations the involvement of non-specialist stakeholders is crucial, which requires transparency of the knowledge base of the risks and benefits concerned. This paper evaluates the basic assumptions of the Organisation for Economic Cooperation and Development regarding the environmental risks of genetically modified micro-organisms, in industrial biotechnology under Good Industrial Large-scale Practice. A clear factual basis for these assumptions could be only partially traced, if at all, and when facts were found they proved to provide only limited support, if any. In addition, several assumptions appeared to be questionable when contrasted with knowledge from chemical and ecological sciences. There remain a number of open questions with respect to risks, most of them relating to improvement and extension of procedures, through greater attention to baselines, safety limits and further standardisation. The necessity of transparency in stakeholder communication is discussed and possible ways of improving such communication are presented. (C) 2009 Elsevier Ltd. All rights reserved.
    https://doi.org/10.1016/j.jclepro.2008.12.011
  • Journal of Ornithology
    2009

    Using eggshell membranes as a DNA source for population genetic research

    K. B. Trimbos, J. Broekman, Rosemarie Kentie, C.J.M. Musters, Geert de Snoo
    In the context of population genetic research, a faster and less invasive method of DNA sampling would allow large-scale assessments of genetic diversity and genetic differentiation with the help of volunteer observers. The aim of this study was to investigate the usefulness of eggshell membranes as a DNA source for population genetic research, by addressing eggshell membrane DNA quality, degeneration and cross-contamination. To this end, a comparison was made with blood-derived DNA samples. We have demonstrated 100% successful DNA extraction from post-hatched Black-tailed Godwit (Limosa limosa) eggshell membranes as well as from blood samples. Using 11 microsatellite loci, DNA amplification success was 99.1% for eggshell membranes and 97.7% for blood samples. Genetic information within eggshell membrane DNA in comparison to blood DNA was not affected (F(ST) = -0.01735, P = 0.999) by degeneration or possible cross-contamination. Furthermore, neither degeneration nor cross-contamination was apparent in total genotypic comparison of eggshell membrane DNA and blood sample DNA. Our research clearly illustrates that eggshell membranes can be used for population genetic research.
    https://doi.org/10.1007/s10336-009-0422-2
  • Biological Conservation
    2009

    Restoration of plant diversity on ditch banks: Seed and site limitation in response to agri-environment schemes

    X. Leng, C.J.M. Musters, Geert de Snoo
    Recently it has become clear that seed limitation is probably a much more important factor in plant recovery than has often been recognized. However, in practice, restoration measures that are focussed on decreasing site limitation may actually increase seed limitation. We tried to determine whether the effects of restoration measures affect site or seed limitation or both. An experiment was set up on ditch banks in the Netherlands which applied agri-environment schemes (AES). To investigate whether nature reserves (seed source) can improve species diversity on the surroundings and to what extent AES is improving this function, we studied the plant diversity (presence of individual species and species richness) of ditch bank vegetations in relation to increasing distance from nature reserves. The presence or absence and species richness of 25 target plants were assessed in 26 ditch banks with AES and 36 non-AES at 15 plots each differing in distance to a nature reserve. Data were analyzed using a Hierarchical Generalized Linear Model (HGLM) with species richness and presence of individual species as response variables and distance to nature reserve and application of AES as factors, controlling for possible confounding factors. Results were interpreted as the effects of AES on seed and site limitation of the species. The results showed that plant diversity decreased significantly with distance from source populations. There were considerable differences in species diversity between AES and non-AES ditch banks, with the former showing greater plant diversity especially in the first 200 m from nature reserves. Presences of all individual species decreased with distance to nature reserve, but the strength of this relationship and the AES effects differed among species. AES ditch banks had lower site limitations for most plant species, but did not have lower seed limitation. (C) 2009 Elsevier Ltd. All rights reserved.
    https://doi.org/10.1016/j.biocon.2009.01.019
  • Biological Conservation
    2008

    The effect of agri-environment schemes on amphibian diversity and abundance

    J. Maes, C.J.M. Musters, Geert de Snoo
    The Western Peat District of The Netherlands has a characteristic Dutch landscape. It consists mainly of meadows for dairy farming, crisscrossed by a dense network of ditches. Its biodiversity is regarded as of high national and international importance, but is declining as a result of intensive farming. Besides the establishment of reserves, measures to conserve and restore biological diversity have been implemented in the form of agri-environment schemes (AES). The aim of this research is to investigate, first, whether the reserves, assuming these provide source populations, affect the distribution of amphibians and, second, whether AES in the form of nature-friendly ditch bank management benefits amphibian diversity and abundance and enhances distribution across the agricultural landscape. In total, 42 ditches (24 control ditches and 18 AES ditches) were studied. Each ditch was perpendicular to the boundary of one of the reserves and was divided into five ditch sections of 100 m spread over 800 m, starting in the reserve and proceeding into the farmland. Generalized Linear Modelling was used to quantify the effect of nature-friendly ditch bank management (AES) and distance to the nature reserve on amphibian diversity and abundance. Species richness was high in AES ditches as compared to control ditches. The number of observed green frog (Rana esculenta synkl.) seemed to decline in the control ditches at large distances from the reserve. The other species, although their abundances were higher in the reserves, did not show a declining trend across the farmland. However, all adult amphibians except green frogs together had significantly higher abundances in the AES ditches compared to the control ditches. These results illustrate the potential role of agricultural ditches, combined with reserves and nature-friendly ditch bank management, in the conservation of amphibian populations. (c) 2007 Elsevier Ltd. All rights reserved.
    https://doi.org/10.1016/j.biocon.2007.12.018
  • Ibis
    2008

    The effectiveness of volunteer nest protection on the nest success of Northern Lapwings Vanellus vanellus on Dutch arable farms

    S. Kragten, J. C. Nagel, Geert de Snoo
    Clutches of ground-nesting farmland birds are often destroyed by farming operations, resulting in insufficient reproductive success and subsequently declining populations. The aim of this study was to investigate whether volunteer nest protection can enhance nest success of ground-nesting birds. The study compared nest success of protected and unprotected Northern Lapwing Vanellus vanellus nests over 2 years on arable farms in the Netherlands. Because of different crop management, nest success of ground-breeding birds might differ between organic and conventional arable farms. The effectiveness of volunteer nest protection was therefore investigated on both farm types. Although nest protection significantly reduced nest loss due to farming operations, there were no significant differences in total clutch survival of protected and unprotected nests. However, sample sizes of unprotected nests, and protected nests on organic farms, were relatively small, which may have reduced statistical power. There were indications that protected nests were predated or deserted more often. We recommend exploring different ways to improve the effectiveness of volunteer nest protection through a further reduction of nest loss due to farming operations and predation.
    https://doi.org/10.1111/j.1474-919X.2008.00842.x
  • Journal for Nature Conservation
    2008

    Evaluation of meadow bird management, especially black-tailed godwit (Limosa limosa L.), in the Netherlands

    Th. C.P. Melman, Alex Schotman, S. Hunink, Geert de Snoo
    Summary Although the protection of meadow birds (amongst others Limosa limosa L.) is a key focus of Dutch nature conservation policy, management schemes (nature reserves and agri-environmental schemes) are not having the desired effect. This study examines the extent to which the disappointing results are related to suboptimal location of the managed sites. First, the extent to which the sites are located outside the core meadow bird area is assessed. Next, the proportion of sites affected by constraints, i.e. road traffic noise, landscape closure, excessive drainage and high predation pressure is analysed. For approximately 43% of these grounds it appears that management effects might be hampered by the aforementioned constraints. The extent to which the findings can explain the lack of ecological effectiveness is then discussed. Finally, we consider how the meadow bird area (ca. 570,000ha) might be managed more effectively through spatial optimisation and how to do so without undermining the support of those carrying out day-to-day management (especially farmers and volunteers).
    https://doi.org/10.1016/j.jnc.2008.01.002
  • Agriculture, Ecosystems and Environment
    2008

    Field-breeding birds on organic and conventional arable farms in the Netherlands

    S. Kragten, Geert de Snoo
    In this study territory densities of field-breeding farmland birds were compared on pairwise-selected organic and conventional arable farms for two years. Differences in territory densities between the two farm types were explained examining the effects of three factors on territory densities: (1) non-crop habitats, (2) crop types and (3) within-crop factors. In both years, densities of most species did not differ between organic and conventional farms. Only skylark and lapwing were more abundant on organic farms, but only skylarks showed a consistent pattern over both years. Differences in crop types grown between the two systems were the only explaining factor for differences in densities of skylark. For lapwing, the difference was only partly due to differences in crop type, but differences in within-crop factors (probably as a result of crop management) were likely to have had an effect as well. There were no significant differences in abundance of non-crop habitats between the two farming systems, so this could not explain differences in territory densities. (C) 2008 Elsevier B.V. All rights reserved.
    https://doi.org/10.1016/j.agee.2008.02.006
  • Journal of Environmental Science and Health Part B-Pesticides Food Contaminants and Agricultural Wastes
    2008

    Spatial and temporal analysis of pesticides concentrations in surface water: Pesticides atlas

    Martina G. Vijver, Maarten van't Zelfde, Will Tamis, K. J. M. Musters, Geert de Snoo
    Dutch water boards have a well-established program for monitoring pesticide contamination of surface waters. These monitoring data have been processed into a graphic format accessible online and designed to provide insight into pesticide presence in Dutch surface waters and trends over time: the Pesticides Atlas (www.pesticidesatlas.nl). With this tool one can easily get maps of where a pesticide is being measured and where it might possibly constitute an environmental problem over the years. Presently, results of the periods 1997/1998 until 2005/2006 are available at the level of individual active ingredients. At a national level, the percentage of pesticides concentrations that exceed the maximum tolerable risk has declined 30% to 38% over the years 2003/2004 compared with 1997/1998. This means that surface water quality in the Netherlands has improved with respect to pesticides, however there are still many locations at which the measured concentrations exceed the environmental quality standards. The results on linking land use to pesticides concentrations were shown to assist in optimization of monitoring programs. By developing the present Internet tool, many new opportunities for environmental risk assessment and risk management were identified, e.g. optimization of monitoring strategies and communication to policymakers.
    https://doi.org/10.1080/03601230802388728
  • Journal of Environmental Management
    2008

    Estimated nationwide effects of pesticide spray drift on terrestrial habitats in the Netherlands

    F.M.W. de Jong, Geert de Snoo, J.C. van de Zande
    This study estimated the potential effects of pesticide drift on terrestrial ecosystems outside target areas, for the Dutch situation. A series of field trials was conducted to estimate the effects of drift on different species groups at different distances from a treated plot for different categories of pesticide: herbicides, fungicides and insecticides. Measurements of the pesticide drift deposition resulting from standard agricultural practice were used to model deposition outside the treated area. These data were then combined with national statistics on cropland and pesticide use to assess the ecological effects of pesticide drift for the Netherlands as a whole. Three scenarios were considered: the recent past (1998), the present (2005) and an optimised scenario based on 'best available practice' (2010). In the recent past the impact of herbicide drift on sensitive life stages non-target vascular plants is estimated to have exceeded the 50% effect level on 59% of adjacent linear landscape elements such as ditch banks and hedgerows. For the impact of insecticides and fungicides on non-target insects and fungi this 50% effect figure was 29% and 28% of linear elements, respectively. In the present situation, with (narrow) unsprayed buffer zones and other measures in place, these percentages are down to 41% for herbicides, 21% for insecticides and 14% for fungicides. In the optimised scenario, with a greater buffer width of 2.25 m for potatoes (compared to 1.50 m in 2005) and I in for other crops (compared to 0.25 and 0.5 m in 2005) and 'best available practice', these percentages can be cut to zero. In natural areas located within farming regions the 10% effect level can be reduced from 31% of such areas (1998) to 0% under conditions of 'best available practice'. (C) 2007 Elsevier Ltd. All rights reserved.
    https://doi.org/10.1016/j.jenvman.2006.12.031
  • 2008

    The Potential of Sustainable Forestry Certification for Smallholder Tree Growing

    Helias A. Udo de Haes, D. J. Snelder, Geert de Snoo
    This chapter's aim is to investigate the potential of sustainable forestry certification for smallholder tree growing. Certification can be important for different stakeholders in the value chain of timber and timber products. By certification, consumers can choose on the basis of more sustainable behavior. For the manufacturing industry, certification can help to improve its image, and in the long run assure its resource input. For the producers of the timber resources, certification can help in achieving market access and can be the basis for long-term sales agreements. There are a number of certification systems for sustainable forestry, some of them operating on a global level, like particularly the Forest Stewardship Council (FSC) and the Programme for Endorsement of Forest Certification schemes (PEFC). However, certification in developing countries lags behind: in 2006 these countries only comprised two percent of the certified forests. A recent FSC program was aimed at timber production by Smallholders and Low Intensity Forests (FSC-SLIMF). This may alleviate the barriers faced by producers in developing countries, for both individual and community forestry. Before starting a process of certification, the costs and benefits along the chain need to be carefully examined, including market perspectives. In general, certification is only useful to an international market, which with others sets requirements on the choice of tree species and timber quality. As a case study, special attention is paid to the potentials of certification of forestry plantations in the Philippines.
    https://doi.org/10.1007/978-1-4020-8261-0_10
  • Agriculture, Ecosystems and Environment
    2008

    Breeding skylarks (Alauda arvensis) on organic and conventional arable farms in The Netherlands

    S. Kragten, K. B. Trimbos, Geert de Snoo
    The aim of this study was to analyse the effects of differences in cropping pattern between organic and conventional arable farms on the breeding activity of skylarks and to assess the effects of arable crop management on skylark nest survival. Skylark nest density was seven times higher on organic farms than on conventional farms (0.63 vs. 0.09 nest per 10 ha). Skylarks showed a strong preference for spring cereals, lucerne and grass leys, all of which were mainly or exclusively grown on organic farms. On organic farms nests were initiated during the entire breeding season, but on conventional farms no nesting activity was found during the peak of the season (early May to early June). On organic farms 27% of all nests was successful. Increasing the availability of suitable breeding habitat during the peak of the breeding season on conventional farms might provide one means of enhancing breeding skylark populations. On organic farms, crop management should focus on reducing nest loss due to fanning operations. (C) 2008 Elsevier B.V. All rights reserved.
    https://doi.org/10.1016/j.agee.2008.01.021
  • Crop Protection
    2008

    Risk assessment of pesticide usage by smallholder farmers in the Cagayan Valley (Philippines)

    D. J. Snelder, M. D. Masipiquena, Geert de Snoo
    A significant increase in pesticide use has increased concerns about potentially adverse effects on human health and the environment, particularly in countries where regulations are not strictly implemented and farmers' knowledge of safe handling procedures is often inadequate. This paper assesses the potential risk of pesticide use by smallholder farmers in the Cagayan Valley, North-East Luzon, the Philippines, by examining pesticide usage, application methods, pesticide drift and health effects among farmers with different levels of income and market access. About 104 farmers growing rice and corn were interviewed and spray drift and exposure of operators was measured when 22 rice farmers sprayed with water using their knapsack equipment. Twenty different pesticides freely sold in stores or markets were encountered in the study, 9 of which are classified as 'highly hazardous' or 'moderately hazardous' and at least 6 as restricted use pesticides. Farmers mostly at risk had the highest income and largest farms. By walking through crops, farmers' legs were most seriously exposed to pesticide deposition. The experimental results agreed with farmers' affirmative response to questions about their suffering various symptoms of poisoning. Estimates of pesticide concentrations in watercourses exposed to drift suggest that aquatic species will suffer adverse effects up to at least 2.0 in from field borders. Hazard quotients suggest that pesticide application rates are not toxic to honeybees exposed to drift up to 1.5 m from sprayed fields. Approval of pesticides needs to distinguish between restricted and general use pesticides. Recommendations are made for controlling pesticide use and its impacts, modifying the integrated pest management programme and redesigning pesticide policies. (c) 2007 Elsevier Ltd. All rights reserved.
    https://doi.org/10.1016/j.cropro.2007.10.011
  • Bird Study
    2007

    Effect of dairy farm management on Swallow Hirundo rustica abundance in The Netherlands

    S. K. Lubbe, Geert de Snoo
    Capsule Dairy farm management methods have no influence on numbers of Swallow breeding pairs. Aim To identify differences in Swallow abundance between organically and conventionally managed dairy farms, by examining three factors: farm buildings, food availability and farmer attitudes to Swallows. Methods Organic and conventional dairy farm holdings were compared in pairwise fashion. On visits to individual farms the number of occupied Swallow nests was counted, the number and type of farm buildings recorded, food availability assessed and the farmer's attitude gauged via a questionnaire. Results No significant difference was found in the number of Swallows on organic and conventional farms. Nor was there any significant difference in food availability or former attitude between the two types of holding. On conventional farms there were significantly more buildings qualifying as preferential Swallow breeding sites, but this did not result in more Swallows on these holdings. Conclusions Our results show that the adopted regime of dairy farm management (conventional versus organic) has no influence on the number of breeding pairs of Swallows.
    https://doi.org/10.1080/00063650709461473
  • Agricultural Research Journal
    2007

    Threats and control of the brown necked ravens (Corvus ruficollis) in Egypt

    Awad A F El-Bahrawy, Martina G. Vijver, Geert de Snoo

    The Suez Canal region is a small fertile area in Egypt that is placed under enormous pressure of existing resources. In these areas, intensive agricultural practices are performed in combination with high population densities. The described problem is that together with agricultural practices and urbanization, Brown necked ravens (Corvus ruficollis) are in huge amounts attracted. The birds are very aggressive and showed to be a serious pest. They spread germs and diseases for human health and food production. Therefore, the birds need to be controlled. Our research focuses on identifying food preferences of raven and on the way raven control is most effective. Ravens are omnivorous birds. From our laboratory study it was seen that most preferable foods were, in descending order: fresh fishes, cow liver, crustacean, watermelons, tomatoes and yoghurt. Under field conditions where stomach content was dissected, animal matters showed to a more preferred food source than plant matters. Observations on olfactory sensitivity showed that ravens could easily locate their food. Biological observations in the field on reproduction of ravens showed that raven females lay two to six eggs. Average number of babies per nest was between one and four. Average number of raven flock before sun rise was more than 100, while it was less than 100 before sun set. The impact of mechanical, biological and chemical control was investigated. Without control, approximately flock numbers of more than 100 ravens were recorded. The average number of raven flock was 60 before mechanical control operation (nests destroyed and using net), while it was 40 after mechanical control. Results of the biological control showed that kestrel (Falco tinnunculus rupicolaeformes) predated raven babies more effective than barn owls (Tyto alba). Within the chemical control experiments, Brodifacoum (0.0005%) was most effective against ravens, followed by Zink phosphide (19%) and Methomyl (90%, carbamate compound).

  • Ibis
    2007

    Nest success of Lapwings Vanellus vanellus on organic and conventional arable farms in the Netherlands

    S. Kragten, Geert de Snoo
    Increasing agricultural intensification has put farmland bird populations under great stress. Although organically managed farms tend to have higher densities of farmland birds than conventionally managed holdings, differences in crop management may also lead to differences in breeding success. With the use of agrochemicals prohibited on organic farms, weeds are controlled using mechanical methods that may pose a threat to ground-nesting birds. This study compares the territory densities and nesting success of the Lapwing Vanellus vanellus on organic and conventional arable farms in the Netherlands. Territory densities were generally higher on organic farms, although in one year nesting success was lower on organic than on conventional farms. This was caused by higher nest loss resulting from farming activities on organic farms. There were no differences in predation rates. The results of this study show that breeding Lapwings may face potential threats on organic farms. To sustain or enhance Lapwing populations on these farms, additional conservation measures should be implemented.
    https://doi.org/10.1111/j.1474-919X.2007.00702.x
  • Agriculture, Ecosystems and Environment
    2007

    Management regimes and farming practices enhancing plant species richness on ditch banks

    A. G. E. Manhoudt, A. J. Visser, Geert de Snoo
    Plant species richness of ditch banks under different fanning practices and management regimes was compared. To this end, species richness was inventoried on ditch banks on Dutch conventional and organic farms and on a number of experimental farms. Plant species richness was significantly higher on organic than conventional farms. On farms that had converted to organic agriculture more than 5 years ago, even more species were found. On all farms, including the experimental farms, higher plant species numbers as well as a higher share of nitrogen poor plant species were found on sandy soils than on clay soils. Also a change in plant species composition was found based on the rarity index and the Ellenberg nitrogen values which was most marked in ecologically managed ditch banks on the experimental farms. The results, therefore, indicated that the ecological management might enhance plant species richness more than organic fanning alone in a 6-year period. In the context of environmental label, criteria designed to enhance on-farm biodiversity should therefore specify an ecological management on ditch banks buffered with a pesticide and nutrient free zone. (c) 2006 Elsevier B.V. All rights reserved.
    https://doi.org/10.1016/j.agee.2006.08.004
  • Communications in agricultural and applied biological sciences
    2007

    Threats and control of the brown necked ravens (Corvus ruficollis) in Egypt

    Awad A F El-Bahrawy, Martina G. Vijver, Geert de Snoo

    The Suez Canal region is a small fertile area in Egypt that is placed under enormous pressure of existing resources. In these areas, intensive agricultural practices are performed in combination with high population densities. The described problem is that together with agricultural practices and urbanization, Brown necked ravens (Corvus ruficollis) are in huge amounts attracted. The birds are very aggressive and showed to be a serious pest. They spread germs and diseases for human health and food production. Therefore, the birds need to be controlled. Our research focuses on identifying food preferences of raven and on the way raven control is most effective. Ravens are omnivorous birds. From our laboratory study it was seen that most preferable foods were, in descending order: fresh fishes, cow liver, crustacean, watermelons, tomatoes and yoghurt. Under field conditions where stomach content was dissected, animal matters showed to a more preferred food source than plant matters. Observations on olfactory sensitivity showed that ravens could easily locate their food. Biological observations in the field on reproduction of ravens showed that raven females lay two to six eggs. Average number of babies per nest was between one and four. Average number of raven flock before sun rise was more than 100, while it was less than 100 before sun set. The impact of mechanical, biological and chemical control was investigated. Without control, approximately flock numbers of more than 100 ravens were recorded. The average number of raven flock was 60 before mechanical control operation (nests destroyed and using net), while it was 40 after mechanical control. Results of the biological control showed that kestrel (Falco tinnunculus rupicolaeformes) predated raven babies more effective than barn owls (Tyto alba). Within the chemical control experiments, Brodifacoum (0.0005%) was most effective against ravens, followed by Zink phosphide (19%) and Methomyl (90%, carbamate compound).

  • Communications in agricultural and applied biological sciences
    2006

    Risk mapping of pesticides

    Geert de Snoo, Will Tamis, Martina G. Vijver, C.J.M. Musters, Maarten van't Zelfde

    Many pesticides are being measured in surface water. To promote the use of monitoring data in the process of risk mapping, post-registration, and improvement of water quality, a free available Internet tool has been developed to present all measurements of pesticides in surface water on the level of individual active ingredients in a spatial framework: the Dutch pesticides atlas (www.pesticidesatlas.nl). With this communication tool one can easily get maps concerning where a pesticide is being measured, observed and possibly constitutes a problem over the years. Pesticide concentrations are being compared with environmental standards and maps can been made of each pesticide at a national level. The pesticide maps have been linked with GIS land use data. At present statistical correlations can be made between crop areas and pesticides concentrations in the water. Moreover, predictions can be made where a pesticide might be exceeding environmental standards. Policy makers, chemical industry (product stewardship), NGO's and farmers can use the maps as a tool for communication and improving environmental quality. The atlas is also being used to evaluate the effectiveness of pesticide policy over the years. In this contribution the methodological background of the pesticides atlas is presented.

  • International Journal of Life Cycle Assessment
    2006

    Benchmarking the environmental performances of farms

    Background, Aim and Scope. The usual route for improvement of agricultural practice towards sustainability runs via labelling schemes for products or farm practices. In most approaches requirements are set in absolute terms, disregarding the variation in environmental performance of farms. Another approach for promoting sustainable farming concerns the concept of benchmarking, which takes into account competition among farmers. The individual agricultural performance is characterized by quantitative criteria and compared with scores of other relevant farms. Methods. Therefore, a pilot study has been conducted in the Netherlands concerning benchmarking among arable farmers in the Internet involving crop protection. A voluntary Dutch benchmark initiative in the Internet is described including farmers' perception regarding the tool. Results. The results show that the benchmark tool in the Internet allows farmers to compare their environmental and economic performance anonymously and securely in a large-scale open-access environment. The pilot group of farmers responded positively to the instrument. An important factor in success is the ease and speed with which data can be entered into the benchmark tool. Conclusions. A benchmark tool for comparing the environmental performance among farmers can form the basis for agreements between farmers and their costumers. An application involving food industry and retailers is discussed.
    https://doi.org/10.1065/lca2006.01.235
  • IOBC/WPRS Bulletin
    2006

    Success stories in landscape management for functional biodiversity: an assessment from 5 west-European countries

    Geert de Snoo, G. Burgio, L. Eggenschwiler, B. Gerowitt, J. Mante, D.W. Powell, F.A.N. van Alebeek, S. Kragten, W.A.H. Rossing, H.-M. Poehling
    Within IOBC, a small scale inventory was made to collect success stories in landscape management for functional biodiversity. Five projects from different European countries were analysed to define the indicators in the people, planet and profit domains being seen as important for success. Projects primarily related to functional biodiversity focused on indicators relevant for farmers, with direct pest/natural enemies assessments and pest management costs and savings considerations at the field and farm level. Projects with a broader emphasis on biological conservation in the countryside often took into account functional biodiversity aspects, but related mostly to a wider range of actors and at a landscape level. Since landscape management for conservation reasons is quite successful it is argued to bring functional biodiversity in line with biodiversity conservation strategies
  • International Journal of Environment and Sustainable Development
    2006

    Scientific transparency for sustainable biotechnology

    A. van Dommelen, Geert de Snoo
    The increasing use of new biotechnologies for industrial production represents a potential contribution to sustainable development. To realise this potential a learning process of stakeholder involvement is needed, supported by a practical tool to make biotechnology debates less confused by stakeholder controversy and more scientifically transparent. We suggest a mechanism of ‘learning-by-questions’ to bridge communication divides between stakeholders and to promote sustainable applications of biotechnology. This new methodology for stakeholder involvement is needed since an innovative realm of genomics-based industrial biotechnology is ready for launch, while the less effective debate on agricultural biotechnology is still frustrating its sustainable development. The aim of this approach is to introduce a more transparent tool for stakeholder involvement, by which possible benefits and costs can be included in a balanced way. For this purpose, we present an integrated perspective on stakeholders, on sustainability and on science.
    https://doi.org/10.1504/IJESD.2006.011558
  • Agriculture, Ecosystems and Environment
    2005

    An indicator of plant species richness of semi-natural habitats and crops on arable farms

    A. G. E. Manhoudt, Helias A. Udo de Haes, Geert de Snoo
    As a straightforward method of assessing on-farm biodiversity, plant species numbers were compared in a fixed sampling area for each type of habitat distinguished independent of farm size and applicable for comparing different farm strategies. Using the species-area relationship, the minimum sampling areas were determined. For ditch banks, crops and field margin strips sampling areas of 400 m(2) (independent of the ditch bank width), 100 and 25 m(2), respectively, were proposed. Indicator threshold values for conventional farms were defined based on the best 10% of the variation in species richness among farms. With appropriate farm management these targets could be achieved. In comparison to ditch banks, crops and sown field margin strips were relatively poor in plant species. The respective numbers of naturally occurring plant species found in crops and field margin were both significantly smaller than those found in ditch banks. In contrast, ecological management of ditch banks appeared to be a promising means of increasing species richness. (c) 2005 Elsevier B.V. All rights reserved.
    https://doi.org/10.1016/j.agee.2005.01.006
  • Pest Management Science
    2004

    Availability of pesticide-treated seed on arable fields

    Geert de Snoo, R. Luttik
    A study of the availability of pesticide-treated seed on arable fields was performed. The research was carried out in three different areas of The Netherlands (soil types ranging between sand and heavy clay) and included the following topics: drilling techniques, soil conditions, location on the field and spillage. The results show that there is a large variation among the various crops in the percentage of seed remaining on the soil surface. This is mainly caused by differences in drilling techniques and soil conditions. The percentage of surface seeds after standard drilling is approximately four times higher than after precision drilling. The best correlation for the impact of soil conditions was found for the overall measure of clod weight. Large differences in seed densities (factor of 3.5) were found between the headland and the field centre. Spillage occured in most crops investigated, with an average of two spills per field. Based on the field data it is recommended to use in the current risk assessment for birds and mammals the following percentages of seed remaining on the soil surface: 0.5% for precision drilling, 3.3% for standard drilling in spring and 9.2% for standard drilling in autumn. (C) 2004 Society of Chemical Industry
    https://doi.org/10.1002/ps.824
  • Communications in agricultural and applied biological sciences
    2004

    Pesticides in the Cagayan valley (Philippines)

    M Baurdoux, D. J. Snelder, Geert de Snoo

    Over the past ten years, the amount and number of different types of pesticides have increased significantly, which led to a growing concern about the possible adverse effects on human health and the environment. This is particularly true for countries where regulations are not strictly implemented and farmers' knowledge of safe handling is often inadequate. This paper discusses the results of a series of spray experiments to determine drift patterns along field boundaries and the exposure of farmers during their usual spraying exercises. Moreover, farmers' pesticide usage and methods of application will be described, and the effects of income and market accessibility on pesticide use patterns will be investigated. It is based on a study conducted in four villages located at increasing distance from the national highway leading to regional markets and connecting the Cagayan Valley in Northeast Luzon with Manila. The 20 pesticides encountered in this study cover 18 different active ingredients, 9 of which are classified by the WHO as 'highly hazardous' or 'moderately hazardous'. The EPA has classified at least 6 of the encountered pesticide formulations as Restricted Use Pesticides. Nevertheless, all pesticides are freely sold in stores or on markets and applied by farmers without personal protection in an unsafe manner. The farmers living nearest to the highway have the highest income and largest farms. Yet they are most at risk, having easiest access to pesticides and spraying the largest quantities of pesticides per hectare, compared to the farmers living at greater distance from the highway. It is recommended to review the list of pesticides approved for use in the Philippines and discern between Restricted and General Use Pesticides. Several recommendations for improving the implementation of pesticide policies and the IPM program are given.

  • Ecotoxicology and Environmental Safety
    2004

    Characterization of grit in arable birds to improve pesticide risk assessment

    R. Luttik, Geert de Snoo
    To describe the grit in bird gizzards, we examined the gizzard content of some 200 birds of varying size and diet (e.g., granivores and nongranivores). Grit use (frequency, size, amount, and shape) was characterized for 27 bird species that forage, at least part of the year, on arable land in the Netherlands. Three different groups could be recognized: the nongranivores with predominantly small grit" particles (the result of inadvertent ingesting soil while foraging), the granivores with larger grit particles (the result of intentionally selecting soil particles), and the group in between (omnivores), which shows features of both other groups. Sample calculations made in this article show a probability of 3-277 in 1000 times for unintentionally consuming one granule. Therefore, attention should also be paid to nongranivorous birds when assessing the hazard or risk of the use of granular pesticide formulations. A risk assessment model is presented in the Appendix. (C) 2003 Elsevier Science (USA). All rights reserved.
    https://doi.org/10.1016/s0147-6513(03)00034-4
  • Tijdschrift voor sociaal wetenschappelijk onderzoek van de landbouw
    2003

    Natuur en Landbouw, nieuwe coalities

  • 2003

    Variations in agricultural practice and environmental care

    Summary This chapter contains sections titled: Introduction Observed variation in agricultural practice Causes of inter-farm variation Environmental impact Environmental prevention
    https://doi.org/10.1002/9780470995457.ch7
  • Agriculture, Ecosystems and Environment
    2003

    A quantitative survey of semi-natural habitats on Dutch arable farms

    A. G. E. Manhoudt, Geert de Snoo
    To enhance biodiversity, guidelines for farm-based nature management recommend that farmers manage at least 5% of their land as semi-natural habitat, in tandem with other measures. Semi-natural habitats are defined here as those areas of a farm that are non-productive, i.e. areas with no intentional inputs of pesticides or nutrients and remaining effectively undisturbed. Reliable information on the actual amount of semi-natural habitat on arable farms was lacking, however. To address this lacuna the absolute and relative area of such habitats was assessed on 105 arable farms in seven regions of The Netherlands. The results on the national level, showed that on conventional Dutch arable farms 2.1% of the holding was managed as semi-natural habitat, a disappointing figure. No marked interregional differences were found, reflecting the high intensity of land use throughout the country. On average, 1.7% of farm holdings were taken up by farmyards, buildings and farm roads and 96.2% by cropped land. Ditch banks were the most common semi-natural habitat on the farms, followed by ditches, hedgerows and dry ditches. Farms participating in field margin projects maintained twice the average figure (5.3 +/- 2.7%) as semi-natural habitat, compared to 2.4 +/- 0.8% without field margins. Comparing conventional with integrated and organic farms revealed no essential difference in the relative amount of semi-natural habitat on each type of farm. (C) 2003 Elsevier Science B.V. All rights reserved.
    https://doi.org/10.1016/s0167-8809(03)00123-3
  • Landscape and Urban Planning
    2003

    A concept of food-web structure in organic arable farming systems

    F. W. Smeding, Geert de Snoo
    A proposal for a descriptive or topological farm food web is derived from field observations and from references in literature. Important themes in the food-web theory are tentatively applied to this preliminary model, explaining differences between local farm food-web structures and how they are related to farm and/or ecological infrastructure (EI) management. Predictions are made for four different farm food-web structures for extremes of farm and environmental gradients corresponding to the length of organic duration and amount/quality of El. The implications with regard to farming practices and nature conservation are that both organic duration and the amount/quality of ecological infrastructure may contribute to ecosystem services and nature conservation. However, an optimisation of the farm food web with regard to ecosystem services, may possibly run counter to nature conservation goals. (C) 2003 Published by Elsevier Science B.V.
    https://doi.org/10.1016/s0169-2046(03)00058-6
  • Agriculture, Ecosystems and Environment
    2002

    A comparison of the environmental impact of pesticide use in integrated and conventional potato cultivation in The Netherlands

    F.M.W. de Jong, Geert de Snoo
    To reduce the environmental impact of agriculture in The Netherlands, a number of labels and certification schemes for integrated farming exist. This article compares the pesticide use associated with ware-potato cultivation by integrated and conventional methods, the former as certified under the Dutch Stichting Milieukeur scheme. Besides kg/ha usage, the potential environmental impact of usage was also compared. In terms of kg applied, on average integrated cultivation involved 25% of the quantities employed in conventional cultivation. This difference was not due to any major difference in the number of pesticides used or in the number of crop treatments; only in the case of herbicides were these figures significantly lower for integrated farming. The principal difference lies in the lower per hectare dosage of the chemicals employed, reducing overall pesticide usage to one-quarter of that employed in conventional cropping. The environmental impact of respective usage was determined using a composite indicator known as the 'environmental yardstick' and the results showed that the impact associated with integrated potato cultivation is only 2% that of conventional cropping. This difference in environmental impact was found for insecticides, fungicides and herbicides and was due to a variety of factors: choice of agent, volume employed and drift reduction. The composition of the crop chemical package played a key role in reducing environmental burden. Even if drift reduction is ignored, integrated cropping as per the Stichting Milieukeur certificate reduced the environmental burden to about 9% of that associated with conventional potato cultivation. (C) 2002 Elsevier Science B.V. All rights reserved.
    https://doi.org/10.1016/s0167-8809(01)00262-6
  • Journal of Environmental Management
    2002

    Environmental labelling in The Netherlands: a framework for integrated farming

    A. G. E. Manhoudt, G. W. J. van de Ven, Helias A. Udo de Haes, Geert de Snoo
    This article compares four Dutch environmental certification schemes for agricultural food crops, analysing their methodology and the completeness of their criteria on five aspects: pesticide use, nutrient use, water management, energy and materials consumption, and habitat management The least stringent of the labels, the MBT (Environmentally Aware Cultivation) certificate, serves mainly to increase farmers' awareness of nutrient and pesticide use. With regard to both administrative obligations and actual management practices, the MBT label largely mirrors the terms of standing Dutch legislation. The CC ('Controlled Cultivation) and AMK (Agro-Environmental) labels comprise more and more stringent criteria. With their restrictions on nutrient and pesticide use, these two labels serve as the two principal labels in the field of integrated agriculture. There is little difference between the two and it is recommended that they be merged, on the basis of a standardised definition of integrated agriculture. The EKO ('Organic Agriculture) label proceeds from different principles, but as a minimum should also comply with Dutch legislation without exception. For both integrated and organic agriculture, in addition to criteria on pesticide and nutrient use, criteria should also be developed for water management energy and materials use and habitat management. The relationship between the criteria and their respective thresholds and Dutch legislation is also addressed. Existing criteria are frequently specified in such a way that the environmental benefits cannot be ascertained. This is a serious drawback for the parties further down the chain: auctioneers, retailers and consumers. It is recommended to develop qualitative guidelines for an Agricultural Stewardship Council at international level, like the Forest Stewardship Council, and a separate label for integrated agriculture per country comprising quantitative criteria for all relevant aspects of farming operations. (C) 2002 Elsevier Science Ltd. All rights reserved.
    https://doi.org/10.1006/jema.2002.0548
  • Landschap
    2002

    Algemene Natuurkwaliteit: soortenrijkdom in relatie tot grondgebruik

    Helias A. Udo de Haes, Geert de Snoo, Will Tamis, K. J. Canters
  • Med. Fac. Landbouww. Univ. Gent
    2001

    Effects of glufosinate-ammonium on off crop vegetation–interim results

    Geert de Snoo, F.M.W. de Jong, R. J. van der Poll, M.G.A.M. van der Linden
  • Mededelingen (Rijksuniversiteit te Gent. Faculteit van de Landbouwkundige en Toegepaste Biologische Wetenschappen)
    2001

    Pesticide residues in human food and wildlife in The Netherlands.

    F.M.W. de Jong, Geert de Snoo
  • Journal of Environmental Management
    2001

    Ecological impacts of arable intensification in Europe

    C. Stoate, Nigel Boatman, R. J. Borralho, C. R. Carvalho, Geert de Snoo, P. Eden
    Although arable landscapes have a long history, environmental problems have accelerated in recent decades. The effects of these changes are usually externalised, being greater for society as a whole than for the farms on which they operate, and incentives to correct them are therefore largely lacking. Arable landscapes are valued by society beyond the farming community, but increased mechanisation and farm size, simplification of crop rotations, and loss of non-crop features, have led to a reduction in landscape diversity. Low intensity arable systems have evolved a characteristic and diverse fauna and flora, but development of high input, simplified arable systems has been associated with a decline in biodiversity. Arable intensification has resulted in loss of non-crop habitats and simplification of plant and animal communities within crops, with consequent disruption to food chains and declines in many farmland species. Abandonment of arable management has also led to the replacement of such wildlife with more common and widespread species. Soils have deteriorated as a result of erosion, compaction, loss of organic, matter and contamination with pesticides, and in some areas, heavy metals. Impacts on water are closely related to those on soils as nutrient and pesticide pollution of water results from surface runoff and subsurface flow, often associated with soil particles, which themselves have economic and ecological impacts. Nitrates and some pesticides also enter groundwater following leaching from arable land. Greatest impacts are associated with simplified, high input arable systems. Intensification of arable farming has been associated with pollution of air by pesticides, NO2 and CO2, while the loss of soil organic matter has reduced the system's capacity for carbon sequestration. International trade contributes to global climate change through long distance transport of arable inputs and products. The EU Rural Development Regulation (1257/99) provides an opportunity to implement measures for alleviating ecological impacts of arable management through a combination of cross-compliance and agri-environment schemes. To alleviate the problems described in this paper, such measures should take account of opportunities for public/private partnerships and should integrate social, cultural; economic and ecological objectives for multifunctional land use. (C) 2001 Academic Press.
    https://doi.org/10.1006/jema.2001.0473
  • Landschap
    2001

    Schoonheid, cultuur en dynamiek

    J.J. Boersema, Geert de Snoo
  • Mededelingen (Rijksuniversiteit te Gent. Faculteit van de Landbouwkundige en Toegepaste Biologische Wetenschappen)
    2001

    Trends of pesticide use in The Netherlands.

    F.M.W. de Jong, Geert de Snoo, T.P.J. Loorij
  • Landscape and Urban Planning
    1999

    Environmental themes on ecolabels

    Geert de Snoo, G. W. J. van de Ven
    A desk study on current market-oriented approaches promoting more sustainable agriculture compared organic farming (ERO), agro-ecolabelling (AMK), 'environmentally-aware cultivation' (MBT), Albert Heijn's controlled cultivation, Sainsbury's integrated crop management and the TNO label developed for the retailer A&P. The contribution of these to individual Dutch environmental policy themes was analysed. The results of an inventory for arable farming are presented, with special reference to the cultivation of ware potatoes. They show that all the labels include the themes of climate change, acidification, eutrophication and ecotoxicity. The themes of hydrological changes and habitat loss and fragmentation are scarcely taken into account in the Dutch labels. This implies that these labels do not guarantee that sustainable agriculture will be developed. However, the British retailer Sainsbury's does consider all the six topics explicitly. Although both the environment and biodiversity will benefit from a reduction of pollutant emissions, the labels do not assess the actual effect of the criteria, as there is no analytical framework for transforming the present ecolabels into manageable and effective instruments to achieve sustainable agriculture. Several criteria are proposed for use in market-oriented tools aiming to enhance biodiversity. (C) 1999 Elsevier Science B.V. All rights reserved.
    https://doi.org/10.1016/s0169-2046(99)00040-7
  • Agriculture, Ecosystems and Environment
    1999

    Effect of herbicide drift on adjacent boundary vegetation

    Geert de Snoo, R. J. van der Poll
    The influence on adjacent ditch-bank vegetation of not spraying crop edges with pesticides was investigated in the Netherlands. To this end, the outer 3-6 m of winter wheat, sugar beet and potato fields were left unsprayed with herbicides and insecticides. The presence and abundance of plant species in adjacent ditch-bank vegetation were compared along sprayed and unsprayed crop edges in the same fields. Only along the unsprayed winter wheat crop did the diversity and cover of dicotyledons increase, as did the floristic value of the vegetation. A lot of species were only found on the ditch banks next to the unsprayed cereal edges, such as Ranunculus repens, Thlaspi arvense, Rumex crispus and Papaver rhoeas. Along this crop no effect was found on monocotyledons. No significant effects were found in the ditch-bank vegetation adjacent to the sugar beet or potato crop. This difference in effect on ditch-bank vegetation among the crops can be explained by differences in the spraying method, herbicides used and dosages employed. (C) 1999 Elsevier Science B.V. All rights reserved.
    https://doi.org/10.1016/s0167-8809(99)00008-0
  • European Review of Agricultural Economics
    1999

    Co-ordinating economic, behavioral and spatial aspects of wildlife preservation in agriculture

    A. Wossink, J. van Wenum, C. Jurgens, Geert de Snoo
    This paper addresses the supply side of wildlife preservation and restoration in agriculture at the regional level. First, we show how network design modelling can be used for economic optimal spatial selection of unsprayed field margins creating a wildlife corridor in the landscape. Second, we analyse the compatibility of field margin management with farmers' perceptions by using the results of conjoint analysis in the spatial optimisation. The theoretical model is implemented by means of a GIS model and an empirical example is added to illustrate the approach.
    https://doi.org/10.1093/erae/26.4.443
  • 1999

    Field Margins and Buffer Zones : Ecology, Management and Policy

    Nigel Boatman, D. H. K. Davies, K. Chaney, R. Feber, Geert de Snoo, T.H. Sparks
  • Landscape and Urban Planning
    1999

    Unsprayed field margins: effects on environment, biodiversity and agricultural practice

    A management strategy developed for field margins to reduce pesticide drift to non-target areas and to promote biodiversity on arable land was investigated. It involved not spraying herbicides and pesticides in a strip 3 or 6 m wide on the edges of winter wheat, sugar beet and potato crops. This strategy was compared with spraying the edges. The effects on pesticide drift, arable flora, invertebrates, vertebrates, costs and acceptance by the farmer were studied. This article reviews the most important results. Interviews with farmers showed that field margins were sprayed intensively. Drift measurements demonstrated that creating unsprayed buffer zones of 3 m width is a very effective way of reducing pesticide drift to the ditches demarcating the field (drift is reduced by about 95%) and risks to aquatic organisms. The presence and abundance of plants associated with arable farming increased substantially in the unsprayed edges, as did the floristic value of the vegetation. The impact on epigeic soil invertebrates was relatively minor. However, there was a pronounced effect on phytophage insects. The number of visits to the unsprayed edges by Motacilla flava flava, an insectivorous bird, also increased. A cost-benefit analysis based on the yield losses showed that it is very feasible to incorporate unsprayed crop edges in the cultivation of winter wheat and potatoes. In sugar beet, however, the cost is too high, However, for reasons to do with agronomy, farming equipment and socio-psychology, farmers will accept unsprayed cereal edges or grass strips but not unsprayed potato edges. From their perspective the most important aspect for acceptance in farming practice is a flexible width of the unsprayed crop edges. (C) 1999 Elsevier Science B.V. All rights reserved.
    https://doi.org/10.1016/s0169-2046(99)00039-0
  • Pesticide Science
    1999

    Vertebrate wildlife incidents with pesticides: a European survey

    Geert de Snoo, N. M. I. Scheidegger, F.M.W. de Jong
    A survey was carried out to investigate terrestrial wildlife incidents with pesticides in 18 European countries over the period 1990-1994. Only in seven countries does a systematic incident registration system exist. Compared with the other countries, relatively high numbers of incidents were registered in France, the Netherlands and the United Kingdom. Over 1000 incidents were investigated to establish their causes: approved use, misuse or deliberate abuse, and the compounds, species and mode of application involved. It was found that most registered incidents are due to deliberate abuse. Approved use is responsible for only a minor fraction of the incidents, and these are due to particular practices such as use of treated seed, bait or wood preservatives and the spraying of grassland. Hardly any incidents were due to crop-spraying. The reason why so few incidents are registered for normal crop-spraying is discussed: do they not occur, or are the casualties not registered? It is doubtful whether incident registration is a reliable instrument for obtaining a proper understanding of the occurrence of the side-effects of agricultural pesticide use. (C) 1999 Society of Chemical Industry.
    https://doi.org/10.1002/ps.2780550109
  • 1998

    Analytical Tools for Chain Management

    Helias A. Udo de Haes, Gjalt Huppes, Geert de Snoo
    A range of tools exists for analysing the materials and energy flows through chains of economic activities. These include life cycle analysis (LCA), materials flow analysis (MFA) and substance flow analysis (SFA), among others. These frameworks, their appropriate use, and their strengths and weaknesses are discussed. The chapter makes clear that these tools must be used within the context of participative decision- and policymaking processes.
    https://doi.org/10.1007/978-94-011-5125-2_5
  • Ecotoxicology and Environmental Safety
    1998

    Buffer zones for reducing pesticide drift to ditches and risks to aquatic organisms

    Geert de Snoo, P.J. de Wit
    Pesticide drift from field sprayers fitted with different types of spray nozzles was investigated under various wind speed conditions. Droplet drift was measured adjacent to the sprayed field, on the ditch bank, and in the ditch. Measurements were carried out in the normal sprayed situation and with an unsprayed buffer zone 3 or 6 m aide. The results indicate that there are major differences between spray nozzles. Drift deposition increases,vith wind speed. In the sprayed situation and with a,wind speed of 0.5 m/s, there was a maximum of 6.0% drift deposition halfway down the ditch bank and no drift deposition in the ditch. At 3 m/s wind speed these figures are 25.1 and 2.2%, respectively. At 5 m/s wind speed, 7.2% drift deposition was measured in the ditch. Risk assessment (cf. SLOOTBOX model) carried out with 17 pesticides used in the study area indicated that at this sind speed, 8 of the 17 pesticides investigated posed a risk to aquatic organisms. Creation of a 3-m buffer zone decreases drift deposition in the ditch by a minimum of 95%, Adjacent to the buffer zone only 4 of the 17 pesticides investigated posed a (minor) risk to aquatic organisms. With a 6-m buffer zone no drift deposition in the ditch could be measured (wind speed maximum, 4.5 m/s). Creating unsprayed crop edges offers good possibilities for the protection of aquatic ecosystems. Socioeconomic research among farmers indicates that buffer zones, such as unsprayed cereal edges and unsprayed grass strips, could well be adopted in agricultural practice. (C) 1998 Academic Press
    https://doi.org/10.1006/eesa.1998.1678
  • Journal of Applied Entomology
    1998

    Butterflies in sprayed and unsprayed field margins

    Geert de Snoo, R. J. van der Poll, J. Bertels
    In the Dutch Field Margin Project a field study was carried out in 1990 and 1992 to investigate the extent to which unsprayed field margins offer scope for increasing butterfly abundance in agricultural areas. To this end the outer 3-6 m of fields of winter wheat or potatoes were left unsprayed with herbicides or insecticides. The number of butterflies in the unsprayed margins was compared with numbers in sprayed margins. Six species were found to be abundant: Maniola jurtina, Lasiommata megera, Coenonympha pamphilus, Pieris rapae, Pier is napi and Thymelicus lincola. In both years in the unsprayed winter wheat edges a significant increase was found in the number of species (approximate to factor of 2.3) and the number of individuals (a factor of 4.6-4.9). In the unsprayed potato edges only in 1992 the increase in the number of species and individuals was significant (a factor of 3.6 and 6.9, respectively). Also at the level of crop edge plus adjacent field boundary (ditch bank and field edge), the number of species and individuals increased significantly in winter wheat in both years, and in potatoes in 1992 only. The ecological relevance of the results is discussed.
  • International Journal of Life Cycle Assessment
    1997

    The agro-production chain environmental management in the agricultural production-consumption chain

    Helias A. Udo de Haes, Geert de Snoo
    After promoting environmental certification of companies in a chain perspective (Udo de Haes & De Snoo, 1996) now the agro-production chain is worked out as a case study. The role of the different links in the chain, such as agricultural producers, processing industry, wholesale companies and retailers is discussed. Also the role of consumers and authorities is described. For every company in the chain the advantages of a company based approach will be a better image and a guaranteed-sale and/or supply. In comparison with a product based approach (ecolabelling) the steering forces in the agro-production chain will be the retailers and not the consumers. Because consumers only get information at company level the approach is less dependent on consumers behaviour in the shop.
    https://doi.org/10.1007/BF02978717
  • Mededelingen van de Faculteit Landbouwwetenschappen, Rijksuniversiteit Gent
    1997

    Variation of pesticide use among farmers in Drenthe: a starting point for environmental protection

    Geert de Snoo, F.M.W. de Jong, R. J. van der Poll, S. E. Janzen, L. J. van der Veen, M. P. Schuemie
  • Agriculture, Ecosystems and Environment
    1997

    Arable flora in sprayed and unsprayed crop edges

    On 15 conventionally managed arable farms in an intensive arable farming district on marine clay in the Netherlands, edges of winter wheat, sugar beet and potato crops were either sprayed or unsprayed with herbicides and insecticides, during the period 1990-1994. The presence (frequency) and abundance (ground cover) of farmland plant species within sprayed and unsprayed edges and in the sprayed field centre were compared. In all three crops, leaving 3-6 m wide edges unsprayed, both the presence and abundance of farmland plants increased, by factors of 4.8-12.1 and 1.5-2.7, respectively. The effect was greatest in the winter wheat crop. The increase was attributable mainly to dicotyledonous species. Although the majority of the plants were common farmland species, there was a major enhancement of the floristic value of the unsprayed fields. In the sprayed centres of the fields, the presence and abundance of farmland plants as well as the overall floristic value were consistently lower than in the sprayed and unsprayed edges. Leaving the crop edges unsprayed significantly decreased crop cover in sugar beet fields only. If compatibility with farm management is also taken into account, the measures investigated appear to have the greatest potential in winter wheat. (C) 1997 Elsevier Science B.V.
    https://doi.org/10.1016/s0167-8809(97)00104-7
  • Journal of Environmental Management
    1996

    Farmers' perception of unsprayed crop edges in the Netherlands

    H. A. B. van der Meulen, Geert de Snoo, G. A. A. Wossink
    This paper argues that not only should environmental and ecological benefits and economic costs be considered in developing nature conservation policies at the farm level but that farmers' perceptions should also be taken into account. Statistical analysis of survey data demonstrates the relevance of these behavioural aspects. Arable farmers with experience of unsprayed crop edges indicated that they preferred unsprayed edges in cereals or grass strips for agronomical, farming equipment related and socio-psychological reasons. The study also focused on the ''ideal'' unsprayed crop edge from the farmers' perspective. It appeared that a flexible width is most important for acceptance in fanning practice, because it is, above all, the width that determines compatibility with existing farming organisation and parcel lay-out. In this respect, there was significant differences between regions. With regard to the payment system, farmers prefer a guaranteed reward instead of a ''payment for nature'' result, irrespective of the region considered. (C) 1996 Academic Press Limited.
    https://doi.org/10.1006/jema.1996.0050
  • International Journal of Life Cycle Assessment
    1996

    Environmental certification

    Helias A. Udo de Haes, Geert de Snoo
  • Journal of Applied Entomology
    1996

    Non-target insects in unsprayed cereal edges and aphid dispersal to the adjacent crop

    Geert de Snoo, J. Deleeuw
    In 1992 and 1993 6 m wide edges of a winter wheat crop were not sprayed with herbicides and insecticides to investigate the impact on the abundance of insects inhabiting the upper parts of the crop and on farmland flowers. To this end, a total of 19 fields were sampled using sweep nets. It was demonstrated that the number of insect groups as well as the insect density increases in the unsprayed edges, by a factor of 1.4 and 3.5, respectively. At the level of the 21 insect groups studied, too, a significant increase in numbers was found for most groups. This held true for aphid predators (mainly Coccinellidae), flower visitors (mainly adult Syrphidae) and insects that form the staple diet of the bird species Motacilla flava flava. Although there was an increase in aphid abundance in most unsprayed edges, the aphids did not spread to the rest of the field, improving the compatibility of unsprayed edges with farm management.
    https://doi.org/10.1111/j.1439-0418.1996.tb01642.x
  • Environmental Toxicology and Chemistry
    1994

    Integral hazard assessment of side-effects of pesticides in the netherlands - a proposal

    Geert de Snoo, K. J. Canters, F.M.W. de Jong, Ruud Cuperus
    Current pesticide registration procedures are discussed and three major shortcomings identified with regard to the quantification and evaluation of potential pesticide side effects on nature and the environment: (a) the absence of a framework for assessing the acceptability of damage; (b) the disregard for indirect side effects; and (c) the absence of field studies. With reference to the situation in The Netherlands, recommendations for overcoming these three shortcomings are presented. For priority species it is proposed that a population decline of more than 5% is unacceptable in target areas having ''general environmental quality.'' Populations should have recovered after one year. Outside the target area and in areas having ''special environmental quality'' there should be no decline at all in population densities. An integral decision tree is presented with which to incorporate assessment of indirect side effects in the registration procedure, achieving a better balance relative to direct side effects. Spectrum of action, scale of use, overlap of habitats, and compound efficacy are employed as criteria for assessing in direct side effects. The decision tree prescribes field trials in cases where lab testing indicates a moderate hazard or uncertainty. Finally, guidelines are presented for selecting appropriate pesticide field trials.
    https://doi.org/10.1897/1552-8618(1994)13[1331:Ihaose]2.0.Co;2
  • Mededelingen van de Faculteit Landbouwwetenschappen, Rijksuniversiteit Gent
    1993

    Use of pesticides along fields margins and ditch banks in the Netherlands

    Geert de Snoo, A. W. Sleeswijk
  • Landschap
    1993

    Algemene Natuurkwaliteit: een prima idee, maar het moet eenvoudig blijven

    Helias A. Udo de Haes, Will Tamis, Geert de Snoo, K. J. Canters

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