6708 PB Wageningen
Prof. dr. ir. Wim H. van der Putten
Wim van der Putten is Head of the Department of Terrestrial Ecology at the Netherlands Institute of Ecology. He graduated at Wageningen University in 1984 and defended his research on 'establishment, growth and degeneration of Ammophila arenaria in coastal foredunes' (performed at the Institute for Ecological Research in Oostvoorne) at Wageningen University in 1989. From 1988 onwards, he was appointed as a Postdoc the institute of Ecology at Heteren. In 1994 he became senior scientist at the department of Plant-Microorganism Interactions and acted as interim head in 1997. In 2000, he became head of the newly established department of Multitrophic Interactions at the Netherlands institute of Ecology (NIOO-KNAW). In September 2003, he was appointed extraordinary professor in Functional Biodiversity at Wageningen University. In 2005, he was awarded a VICI-grant from NWO-ALW (the Dutch research council), and in 2012 he obtained an ERC-Advanced grant from the European Research Council. Currently.
Wim has been associate editor of the Journal of Coastal Research, Plant and Soil, Plant Biology, the Journal of Applied Ecology, Oikos and Oecologia. Currently, he is associate editor of Ecology Letters and Board Reviewing Editor at Science. Since 1992, he has been coordinator of a number of European research projects (EUREED, CLUE, INVASS, EcoTrain), as well as PI in others (TLinks, Biorhiz, Consider, Soilservice, EcoFinders, and Liberation). He has been co-editor of a book on Soil Ecology, as well as on the European Atlas of Soil Biodiversity.
In 2010 he initiated the Wageningen Centre for Soil Ecology (CSE; http://www.soilecology.eu/) and since then he is chairman of the daily board. Aims of this centre are to stimulate utilization of knowledge from fundamental research and to attract and support young researchers in soil ecology. In 2011, he was one of the founders of the Global Soil Biodiversity Initiative (GSBI; http://www.globalsoilbiodiversity.org/) that integrates and disseminates information on the biological status of soils world-wide, a.o. serving as an expert centre for FAO, CBD and other global organizations.
Awards and distinctions
2021 Elected member of Academia Europaea
2020 Marie Curie award to Lilia Serrano
2019 Marie Curie individual grants to Safaa Wasof and Elizabeth Wandrag
2013 Co-author on paper by O. Kostenko et al. Ecology Letters 2012: NERN-prize and PE&RC prize of best paper 2012
2012 ERC-Advanced grant on 'aboveground-belowground community re-assemblages under global warming'
2012 Co-author on paper by T.F.J. van de Voorde et al.: runner-up for John Harper prize from Journal of Ecology
2009 Visiting scientist at Centre for Population Biology, Imperial College at Silwood Park, UK
2008 Co-author on paper by T. Engelkes et al. receiving the NERN-prize 2008
2007 Teachers award Wageningen University
2006 Co-author of paper by R. Soler et al. receiving Charles Elton award from the Journal of Animal Ecology
2005 Co-author of paper by G.B. De Deyn et al. receiving John Harper award from the Journal of Ecology
2004 VICI-award Dutch Research Council for personal innovation
2003/4 Visiting scientist at Landcare Research institute New Zealand
Main research areas
The research of Wim van der Putten has shown how soil-borne pathogens and parasites can drive compositional change in natural vegetation (Nature, 1993). Before that time, the traditional view in ecology was that symbiotic soil biota (mycorrhizal fungi and nitrogen-fixing microbes) and abiotic soil conditions (nutrients, pH, porosity, structure, and water availability) were the main belowground drivers of species composition and productivity of natural vegetation. His breakthrough on the role of soil-borne pathogens has stimulated numerous studies that advance understanding the role of plant-soil feedback interactions in functioning of natural ecosystems. He and coworkers have demonstrated that these feedback interactions promote diversity in plant communities (De Deyn et al. Nature, 2003), which is important information for ecological restoration, and that plant species that successfully shift range under current climate warming have similar properties as invasive species because of escape from aboveground and belowground enemies (Engelkes and Morrien et al. Nature, 2008). He and co-workers showed that extreme weather events may remain as legacy effects in the soil biota thus influencing plant invasiveness (PNAS, 2013). Future breakthroughs are expected to come from his ERC advanced grant (awarded in 2012), which enables him to gain insights in belowground-aboveground community re-assemblage process following climate warming-induced range shifts. These insights will provide fundamental understanding of ecological-evolutionary dynamics in terrestrial communities, which may lead to novel ways of ecosystem management by enhancing adaptation in natural communities to global environmental changes. Wim is also known for his contributions to many conceptual papers, such as on aboveground-belowground interactions (Van der Putten et al. TREE, 2001, Wardle et al. Science, 2004), species range shifts under climate warming (Van der Putten AREES 2012), species gain and loss (Wardle et al. Science, 2011), and belowground biodiversity and ecosystem functioning (Bardgett and Van der Putten Nature, 2014).
Recent books & reports
Jeffery S, Gardi C, Jones A, Montanarella L, Marmo L, Miko L, Ritz K, Peres G, Römbke J. and Van der Putten WH (eds.), 2010, European Atlas of Soil Biodiversity. European Commission, Publications Office of the European Union, Luxembourg. ISBN 978-92-79-15806-3, ISSN 1018-5593, doi 10.2788/94222, 128 pp.
Wall, D.H., Bardgett, R.D., Behan-Pelletier, V., Herrick, J.E., Jones, T.H., Ritz, K., Six, J., Strong, D.R., and van der Putten, W.H. (eds.) 2012. Soil Ecology and Ecosystem Services. Oxford: Oxford University Press.
Turbé, A, De Toni, A, Benito, P, Lavelle, P, Lavelle, P, Ruiz, N, Van der Putten, W.H., Labouze, E, and Mudgal, S. 2010 Soil biodiversity: functions, threats and tools for policy makers. Bio Intelligence Service, IRD, and NIOO, Report for European Commission (DG Environment), Brussels.
Rhizosphere 4 Conference (June 21-25, 2015, Maastricht, The Netherlands)
Management and organization
2017- Member of the RNWT of the KNAW
2016- Review panel KNAW Fund Ecology
2016-2017 Advisory board 2nd Global Soil Biodiversity Conference, Nanjing, China
2016-2018 Chair EASAC Committee on Soils at Risk
2016 Onderwijsprijs (Education prize) 2016 committee KNAW
2016 Evaluation committee environment panel Strategic Alliances Netherlands-China
2014-2017 Technical Chairman VICI committee of Dutch Research Council Life Sciences
2013- Chairman Althof Foundation
2012- Member of Editors group of Global Soil Biodiversity Atlas
2012- Organization committee of Soil Biodiversity symposium (Dijon, 2014)
2012- Member of organization of Rhizosphere 4 conference (Maastricht, 2015)
2012- Chairman De Levende Natuur Foundation
2012- Management team BE-Basic project
2012- Scientific Advisory Committee Gegevensautoriteit (Dutch Authority for Ecological Data)
2011- Member daily board Global Soil Biodiversity Initiative (GSBI)
2011- PI-Management Team Jena Experiment
2010- Chairman daily board Centre for Soil Ecology NIOO-WUR
2010- Scientific Advisory Board Centre for Functional Ecology, University of Coimbra, Portugal
2010- Steering Committee Ecotron CEFE-CNRS Montpellier
2010-2011 Member Knowledge Table SKB
2008-2012 Functional Agro Biodiversity Steering Committee
2006-2008 NWO-ALW VIDI committee
2006-2008 NWO Mozaiek committee (chairman in 2008)
2006-2007 Year Planet Earth Steering Committee
2002-2006 Coordinator EU-Ecotrain
2002-2005 Daily Board EU-TLinks
2002-2011 Replacing Director of Centre for Terrestrial Ecology
1997- NWO-ALW ad hoc selection committees
1997-1999 Coordinator EC-INVASS project
1996-1998 Coordinator EC-CLUE project
1996-1999 Board of the Dutch-Flemish Ecological Society (Secretary)
1994-1995 Coordinator EC-EUREED project
1992 Interim management Bird Ring Department at the Institute for Ecological Research
1989-1991 Coordinator Applied Ecology projects at the Institute for Ecological Research
Soils contain biotic and abiotic legacies of previous conditions that may influence plant community biomass and associated aboveground biodiversity. However, little is known about the relative strengths and interactions of the various belowground legacies on aboveground plant–insect interactions. We used an outdoor mesocosm experiment to investigate the belowground legacy effects of range-expanding versus native plants, extreme drought and their interactions on plants, aphids and pollinators. We show that plant biomass was influenced more strongly by the previous plant community than by the previous summer drought. Plant communities consisted of four congeneric pairs of natives and range expanders, and their responses were not unanimous. Legacy effects affected the abundance of aphids more strongly than pollinators. We conclude that legacies can be contained as soil ‘memories’ that influence aboveground plant community interactions in the next growing season. These soil-borne ‘memories’ can be altered by climate warming-induced plant range shifts and extreme drought.
Background and aims: Plants continuously interact with soil microbiota. These plant-soil feedbacks (PSFs) are considered a driving force in plant community dynamics. However, most PSF information comes from inter-family studies, with limited information on possible causes. We studied the variation of PSFs between and within grass species and identified the soil microbes that are associated with the observed PSFs effects. Methods: We grew monocultures of ten cultivars of three grass species (Lolium perenne, Poa pratensis, Schedonorus arundinaceus) using a two-phase PSF experiment. We measured plant total biomass to determine PSFs between and within species and correlated it with sequenced rhizosphere bacteria and fungi. Results: In the soil conditioning phase, grass species developed microbial legacies that affected the performance of other grass species in the feedback phase. We detected overall negative interspecific PSFs. While we show that L. perenne and P. pratensis increased their performance respectively in conspecific and heterospecific soils, S. arundinaceus was not strongly affected by the legacies of the previous plant species. Contrary to our expectation, we found no evidence for intraspecific variation in PSFs. Bacterial taxa associated with PSFs included members of Proteobacteria, Firmicutes, Verrucomicrobia and Planctomycetes whereas fungal taxa included members of Ascomycota. Conclusion: Our results suggest differences in PSF effects between grass species, but not between cultivars within species. Thus, in the studied grass species, there might be limited potential for breeding on plant traits mediated by PSFs. Furthermore, we point out potential microbial candidates that might be driving the observed PSF effects that could be further explored.
Climate change is causing range shifts of many species to higher latitudes and altitudes and increasing their exposure to extreme weather events. It has been shown that range-shifting plant species may perform differently in new soil than related natives; however, little is known about how extreme weather events affect range-expanding plants compared to related natives. In this study we used outdoor mesocosms to study how range-expanding plant species responded to extreme drought in live soil from a habitat in a new range with and without live soil from a habitat in the original range (Hungary). During summer drought, the shoot biomass of the range-expanding plant community declined. In spite of this, in the mixed community, range expanders produced more shoot biomass than congeneric natives. In mesocosms with a history of range expanders in the previous year, native plants produced less biomass. Plant legacy or soil origin effects did not change the response of natives or range expanders to summer drought. During rewetting, range expanders had less biomass than congeneric natives but higher drought resilience (survival) in soils from the new range where in the previous year native plant species had grown. The biomass patterns of the mixed plant communities were dominated by Centaurea spp.; however, not all plant species within the groups of natives and of range expanders showed the general pattern. Drought reduced the litter decomposition, microbial biomass, and abundances of bacterivorous, fungivorous, and carnivorous nematodes. Their abundances recovered during rewetting. There was less microbial and fungal biomass, and there were fewer fungivorous nematodes in soils from the original range where range expanders had grown in the previous year. We concluded that in mixed plant communities of range expanders and congeneric natives, range expanders performed better, under both ambient and drought conditions, than congeneric natives. However, when considering the responses of individual species, we observed variations among pairs of congenerics, so that under the present mixed-community conditions there was no uniformity in responses to drought of range expanders versus congeneric natives. Range-expanding plant species reduced soil fungal biomass and the numbers of soil fungivorous nematodes, suggesting that the effects of range-expanding plant species can trickle up in the soil food web.
Beneficial soil microbes can enhance plant growth and defense, but the extent to which this occurs depends on the availability of resources, such as water and nutrients. However, relatively little is known about the role of light quality, which is altered during shading, resulting a low red: far-red ratio (R:FR) of light. We examined how low R:FR light influences arbuscular mycorrhizal fungus (AMF)-mediated changes in plant growth and defense using Solanum lycopersicum (tomato) and the insect herbivore Chrysodeixis chalcites. We also examined effects on third trophic level interactions with the parasitoid Cotesia marginiventris. Under low R:FR light, non-mycorrhizal plants activated the shade avoidance syndrome (SAS), resulting in enhanced biomass production. However, mycorrhizal inoculation decreased stem elongation in shaded plants, thus counteracting the plant’s SAS response to shading. Unexpectedly, activation of SAS under low R:FR light did not increase plant susceptibility to the herbivore in either non-mycorrhizal or mycorrhizal plants. AMF did not significantly affect survival or growth of caterpillars and parasitoids but suppressed herbivore-induced expression of jasmonic acid-signaled defenses genes under low R:FR light. These results highlight the context-dependency of AMF effects on plant growth and defense and the potentially adverse effects of AMF under shading.
Evaluation of restoration activities is indispensable to assess the extent to which targets have been reached. Usually, the main goal of ecological restoration is to restore biodiversity and ecosystem functioning, but validation is often based on a single indicator, which may or may not cope with whole-ecosystem dynamics. Network analyses are, however, powerful tools, allowing to examine both the recovery of various biotic and abiotic properties and the integrated response at community and ecosystem level. We used restoration sites where topsoil was removed from former intensively managed grassland and seeds were added. These sites were between 3 and 32 years old. We assessed how plants, soil biota, soil properties and correlation-based interactions between biotic communities and their abiotic environment developed over time and compared the results with (i) intensively managed (not restored), and (ii) well-preserved targeted semi-natural grasslands. Plant, nematode, fungal and prokaryotic diversity and community structures of the restored grasslands revealed clear successional patterns and followed similar trajectories towards targeted semi-natural grasslands. All biotic communities reached targeted diversity levels no later than 18 years post-restoration. Ecological networks of intensively managed and short-term (~4 years) restored grasslands were less tightly connected compared to those found in mid- and long-term (~18–30 years) restored and target grasslands. Restoration specifically enhanced interactions among biotic communities, but reduced interactions between biotic communities and their abiotic environment as well as interactions among abiotic properties in the short- and mid-term. Synthesis and applications: Overall, our study demonstrated that topsoil removal and seed addition were successful in restoring diverse, tightly coupled and well-connected biotic communities above- and below-ground similar to those found in the semi-natural grasslands that were restoration targets. Network analyses proved to be powerful in examining the long-term re-establishment of functionally connected biotic communities in restored ecosystems. Thus, we provide an approach to holistically assess restoration activities by notably considering the complexity of ecosystems, much in contrast to most traditional approaches.
Plant and soil microbial community composition play a central role in maintaining ecosystem functioning. Most studies have focused on soil microbes in the bulk soil, the rhizosphere and inside plant roots, however, less is known about the soil community that exists within soil aggregates, and how these soil communities influence plant biomass production. Here, using field-conditioned soil collected from experimental ungrazed and grazed grasslands in Inner Mongolia, China, we examined the composition of microbiomes inside soil aggregates of various size classes, and determined their roles in plant-soil feedbacks (PSFs), diversity-productivity relationships, and diversity-dependent overyielding. We found that grazing induced significantly positive PSF effects, which appeared to be mediated by mycorrhizal fungi, particularly under plant monocultures. Despite this, non-additive effects of microbiomes within different soil aggregates enhanced the strength of PSF under ungrazed grassland, but decreased PSF strength under intensively grazed grassland. Plant mixture-related increases in PSF effects markedly enhanced diversity-dependent overyielding, primarily due to complementary effects. Selection effects played far less of a role. Our work suggests that PSF contributes to diversity-dependent overyielding in grasslands via non-additive effects of microbiomes within different soil aggregates. The implication of our work is that assessing the effectiveness of sustainable grassland restoration and management on soil properties requires inspection of soil aggregate size-specific microbiomes, as these are relevant determinants of the feedback interactions between soil and plant performance.
Aviation biofuels are promising to reduce carbon emissions in the aviation sector. However, emerging concerns over biofuels indicate a need for sustainability analyses that take into consideration the context around biofuel production. Here, we present a novel ex-ante sustainability analysis of production alternatives for aviation biofuel in Southeast Brazil. Considering local stakeholders’ concerns, the analysis is focused on climate change, commercial acceptability, efficiency, energy security, investment security, profitability, social development, and soil sustainability. By identifying tensions between production alternatives and these sustainability aspects, we discuss opportunities for further developments, such as sugarcane ethanol-to-jet production in the short term, and in-house production of hydrogen and power with renewable energy. Additionally, producer–operator partnerships and opening the decision-making to stakeholder participation are suggested to stimulate social cohesion, and reconcile diverging interests with biobased production. Analyzing sustainability with consideration of the local context can contribute to identify opportunities for more sustainable decarbonization alternatives.
Global change frequently disrupts the connections among species, as well as among species and their environment, before the most obvious impacts can be detected. Therefore, we need to develop a unified conceptual framework that allows us to predict early ecological impacts under changing environments. The concept of coupling, defined as the multiple ways in which the biotic and abiotic components of ecosystems are orderly connected across space and/or time, may provide such a framework. Here, we operationally define the coupling of ecosystems based on a combination of correlational matrices and a null modeling approach. Compared with null models, ecosystems can be (1) coupled; (2) decoupled; and (3) anticoupled. Given that more tightly coupled ecosystems displaying higher levels of internal order may be characterized by a more efficient capture, transfer, and storage of energy and matter (i.e., of functioning), understanding the links between coupling and functioning may help us to accelerate the transition to planetary-scale sustainability. This may be achieved by promoting self-organized order.
Embedded in longer term warming are extreme climatic events such as heatwaves and droughts that are increasing in frequency, duration and intensity. Changes in climate attributes such as temperature are often measured over larger spatial scales, whereas environmental conditions to which many small ectothermic arthropods are exposed are largely determined by small-scale local conditions. Exposed edges of plant patches often exhibit significant short-term (daily) variation to abiotic factors due to wind exposure and sun radiation. By contrast, within plant patches, abiotic conditions are generally much more stable and thus less variable. Over an eight-week period in the summer of 2020, including an actual heatwave, we measured small-scale (1 m2) temperature variation in patches of forbs in experimental mesocosms. We found that soil surface temperatures at the edge of the mesocosms were more variable than those within mesocosms. Drought treatment two years earlier, amplified this effect but only at the edges of the mesocosms. Within a plant patch both at the soil surface and within the canopy, the temperature was always lower than the ambient air temperature. The temperature of the soil surface at the edge of a patch may exceed the ambient air temperature when ambient air temperatures rise above 23 °C. This effect progressively increased with ambient temperature. We discuss how microscale-variation in temperature may affect small ectotherms such as insects that have limited ability to thermoregulate, in particular under conditions of extreme heat.
1. Climate change is known to disrupt above-ground food chains when the various trophic layers respond differently to warming. However, little is known about below-ground food chains involving microbial preys and their predators. Here, we study how climate warming-induced heat shocks influence resistance (change immediately after a disturbance) and resilience (ability to recover back to pre-disturbance levels) in rhizosphere microbial communities.
2. We used three species of rhizosphere protists as microbial predators and six different rhizosphere bacterial communities as their prey. Protist species and bacterial communities were extracted from Centaurea stoebe—a range-expanding plant species in the Northern Europe. We then examined the temporal dynamics of protists and bacterial communities after an extreme heat event for several generations with sufficient recovery periods. We hypothesized that bacterial community resistance and resilience after the extreme heat event would be higher particularly when extreme heat effects would negatively affect their predators.
3. Our results show that prey community biomass was strongly reduced after the extreme heat event and persisted with lower biomass throughout the recovery period. Opposite to what was expected, predators showed negligible changes in their active density after the same heat event. However, abundances of the three predators varied markedly in their temporal dynamics independent of the extreme heat event. Extreme heat event further increased the inactive density of predators, whereas one of the predators showed a decline in its body size owing to extreme heat event. Bacterial community resistance and resilience after the extreme heat event were independent of predator presence, although species-specific effects of predators on bacterial community resilience were different in the last week of recovery. Predator resilience (based on active predator density) also varied among the three predators but converged over time.
4. Our results highlight that extreme heat events can be more detrimental to microbial prey communities than microbial predators when microbial predators can exhibit thermal acclimation (e.g. change in body size or become inactive) to overcome heat stress. Such thermal acclimation may promote predator resilience after extreme heat events.
The restoration of Nardus grasslands is often hampered by high bioavailability of soil phosphorus and disturbed soil communities. In order to better understand these bottlenecks, we studied Nardus grassland species grown together in communities with fast-growing species in 50-liter pots along a gradient of bioavailable phosphorus with or without inoculated soil biota. These mesocosms allowed the plants to freely interact, including competition for light and nutrients. We investigated changes in the plant community composition along the phosphorus gradient using Threshold Indicator Taxa Analysis (TITAN). We found a negative threshold of 11.5 mg POlsen kg−1 with six significant indicator plant species. Above the threshold, a small increase in phosphorus resulted in a disproportionally large drop in biomass for the indicator species, including four typical Nardus grassland species. The decline in these ‘oligotrophic indicator species’ was also linked to increasing plant community biomass, so we suggest the oligotrophic indicator species to be outcompeted for light by fast-growing plant species. We did not find an effect of the soil biota treatment on the biomass of the oligotrophic indicator species, but did observe a positive effect of inoculation with soil biota on the total biomass of the plant community. Interestingly, the threshold for the plant communities in the mesocosm experiment was comparable to the upper bioavailable phosphorus concentrations in remnant Nardus grasslands in northern Belgium. For the restoration of Nardus grasslands, such phosphorus-poor soil conditions appear to be essential, because the plant species that typically occur in these grasslands are able to handle nutrient limitation, but not light limitation.
It is generally assumed that restoring biodiversity will enhance diversity and ecosystem functioning. However, to date, it has rarely been evaluated whether and how restoration efforts manage to rebuild biodiversity and multiple ecosystem functions (ecosystem multifunctionality) simultaneously. Here, we quantified how three restoration methods of increasing intervention intensity (harvest only < topsoil removal < topsoil removal + propagule addition) affected grassland ecosystem multifunctionality 22 yr after the restoration event. We compared restored with intensively managed and targeted seminatural grasslands based on 13 biotic and abiotic, above- and belowground properties. We found that all three restoration methods improved ecosystem multifunctionality compared to intensively managed grasslands and developed toward the targeted seminatural grasslands. However, whereas higher levels of intervention intensity reached ecosystem multifunctionality of targeted seminatural grasslands after 22 yr, lower intervention missed this target. Moreover, we found that topsoil removal with and without seed addition accelerated the recovery of biotic and aboveground properties, and we found no negative long-term effects on abiotic or belowground properties despite removing the top layer of the soil. We also evaluated which ecosystem properties were the best indicators for restoration success in terms of accuracy and cost efficiency. Overall, we demonstrated that low-cost measures explained relatively more variation of ecosystem multifunctionality compared to high-cost measures. Plant species richness was the most accurate individual property in describing ecosystem multifunctionality, as it accounted for 54% of ecosystem multifunctionality at only 4% of the costs of our comprehensive multifunctionality approach. Plant species richness is the property that typically is used in restoration monitoring by conservation agencies. Vegetation structure, soil carbon storage and water-holding capacity together explained 70% of ecosystem multifunctionality at only twice the costs (8%) of plant species richness, which is, in our opinion, worth considering in future restoration monitoring projects. Hence, our findings provide a guideline for land managers how they could obtain an accurate estimate of aboveground-belowground ecosystem multifunctionality and restoration success in a highly cost-efficient way.
The mycobiome (fungal microbiome) influences plants—from seed germination to full maturation. While many studies on fungal-plant interaction studies have focused on known mutualistic and pathogenic fungi, the functional role of ubiquitous endophytic fungi remains little explored. We examined how root-inhabiting fungi (endophytes) influence range-expanding plant species. We isolated endophytes from three European intra-continental range-expanders and three congenerics that are native both in the range expander's original (southern Europe) and new (northern Europe) range. To standardize our collection, endophytes were obtained from all six plant species growing under controlled conditions in northern (new range of the range expander) and southern (native range of the range expander) soils. We cultivated, molecularly identified and tested the effects of all isolates on seed germination, and growth of seedlings and older plants. Most of the 34 isolates could not be functionally characterized based on their taxonomic identity and literature information on functions. Endophytes affected plant growth in a plant species–endophyte-specific manner, but overall differed between range-expanders and natives. While endophytes reduced germination and growth of range-expanders compared to natives, they reduced seedling growth of natives more than of range-expanders. Synthesis. We conclude that endophytic fungi have a direct effect on plant growth in a plant growth stage-dependent manner. While these effects differed between range expanders and natives, the effect strength and significance varied among the plant genera included in the present study. Nevertheless, endophytes likely influence the establishment of newly arriving plants and influence vegetation dynamics.
Establishment and growth of grassland plant species is generally promoted by arbuscular mycorrhizal fungi (AMF) when grown in isolation. However, in grassland communities AMF form networks that may connect individual plants of different ages within and between species. Here, we use an ingrowth core approach to examine how mycorrhizal networks influences performance of seedlings in grasslands. We selected four grass and four forb species with known negative or neutral-positive plant–soil feedback and grew them individually in steel mesh cores filled with living field soil. Cores were placed in six restored grasslands, three grasslands were of relatively young and three were of older successional age. Ingrowing mycorrhizal fungal hyphae were severed twice a week in half of all cores, which resulted into reduced AMF colonization and increased seedling biomass, irrespective of the fields' succession stage, and the plants' grass/forb group, or plant–soil feedback type. In the control cores, root colonization by AMF was negatively correlated to seedling biomass, whereas there was no such relationships in the cores that had been lifted. We conclude that connections to arbuscular mycorrhizal networks of surrounding plants had a negative impact on biomass of establishing forb and grass seedlings.
Plant–soil feedback (PSF) and diversity–productivity relationships are important research fields to study drivers and consequences of changes in plant biodiversity. While studies suggest that positive plant diversity–productivity relationships can be explained by variation in PSF in diverse plant communities, key questions on their temporal relationships remain. Here, we discuss three processes that change PSF over time in diverse plant communities, and their effects on temporal dynamics of diversity–productivity relationships: spatial redistribution and changes in dominance of plant species; phenotypic shifts in plant traits; and dilution of soil pathogens and increase in soil mutualists. Disentangling these processes in plant diversity experiments will yield new insights into how plant diversity–productivity relationships change over time.
Plant-soil feedbacks (PSFs) have been shown to strongly affect plant performance under controlled conditions, and PSFs are thought to have far reaching consequences for plant population dynamics and the structuring of plant communities. However, thus far the relationship between PSF and plant species abundance in the field is not consistent. Here, we synthesize PSF experiments from tropical forests to semiarid grasslands, and test for a positive relationship between plant abundance in the field and PSFs estimated from controlled bioassays. We meta-analyzed results from 22 PSF experiments and found an overall positive correlation (0.12 ≤ (Formula presented.) ≤ 0.32) between plant abundance in the field and PSFs across plant functional types (herbaceous and woody plants) but also variation by plant functional type. Thus, our analysis provides quantitative support that plant abundance has a general albeit weak positive relationship with PSFs across ecosystems. Overall, our results suggest that harmful soil biota tend to accumulate around and disproportionately impact species that are rare. However, data for the herbaceous species, which are most common in the literature, had no significant abundance-PSFs relationship. Therefore, we conclude that further work is needed within and across biomes, succession stages and plant types, both under controlled and field conditions, while separating PSF effects from other drivers (e.g., herbivory, competition, disturbance) of plant abundance to tease apart the role of soil biota in causing patterns of plant rarity versus commonness.
Biobased production has been promoted as an alternative to fossil-based production to mitigate climate change. However, emerging concerns over the sustainability of biobased products have shown that tensions can emerge between different objectives and concerns, like emission reduction targets and food security, and that these are dependent on local contexts. Here we present the Open Sustainability-in-Design (OSiD) framework, the aim of which is to integrate a context-sensitive sustainability analysis in the conceptual design of biobased processes. The framework is illustrated, taking as an example the production of sustainable aviation fuel in southeast Brazil. The OSiD framework is a novel concept that brings the perspectives of stakeholders and considerations of the regional context to an ex ante sustainability analysis of biobased production. This work also illustrates a way to integrate methods from different scientific disciplines supporting the analysis of sustainability and the identification of tensions between different sustainability aspects. Making these tensions explicit early in the development of biobased production can make them more responsive to emerging sustainability concerns. Considering the global pressure to reduce carbon emissions, situating sustainability analyses in their socio-technical contexts as presented here can help to explain and improve the impacts of biobased production in the transition away from fossil resources.
Earthworms are an important soil taxon as ecosystem engineers, providing a variety of crucial ecosystem functions and services. Little is known about their diversity and distribution at large spatial scales, despite the availability of considerable amounts of local-scale data. Earthworm diversity data, obtained from the primary literature or provided directly by authors, were collated with information on site locations, including coordinates, habitat cover, and soil properties. Datasets were required, at a minimum, to include abundance or biomass of earthworms at a site. Where possible, site-level species lists were included, as well as the abundance and biomass of individual species and ecological groups. This global dataset contains 10,840 sites, with 184 species, from 60 countries and all continents except Antarctica. The data were obtained from 182 published articles, published between 1973 and 2017, and 17 unpublished datasets. Amalgamating data into a single global database will assist researchers in investigating and answering a wide variety of pressing questions, for example, jointly assessing aboveground and belowground biodiversity distributions and drivers of biodiversity change.
Soil organisms, including earthworms, are a key component of terrestrial ecosystems. However, little is known about their diversity, their distribution, and the threats affecting them. We compiled a global dataset of sampled earthworm communities from 6928 sites in 57 countries as a basis for predicting patterns in earthworm diversity, abundance, and biomass. We found that local species richness and abundance typically peaked at higher latitudes, displaying patterns opposite to those observed in aboveground organisms. However, high species dissimilarity across tropical locations may cause diversity across the entirety of the tropics to be higher than elsewhere. Climate variables were found to be more important in shaping earthworm communities than soil properties or habitat cover. These findings suggest that climate change may have serious implications for earthworm communities and for the functions they provide.
Soil organisms are a crucial part of the terrestrial biosphere. Despite their importance for ecosystem functioning, few quantitative, spatially explicit models of the active belowground community currently exist. In particular, nematodes are the most abundant animals on Earth, filling all trophic levels in the soil food web. Here we use 6,759 georeferenced samples to generate a mechanistic understanding of the patterns of the global abundance of nematodes in the soil and the composition of their functional groups. The resulting maps show that 4.4 ± 0.64 × 1020 nematodes (with a total biomass of approximately 0.3 gigatonnes) inhabit surface soils across the world, with higher abundances in sub-Arctic regions (38% of total) than in temperate (24%) or tropical (21%) regions. Regional variations in these global trends also provide insights into local patterns of soil fertility and functioning. These high-resolution models provide the first steps towards representing soil ecological processes in global biogeochemical models and will enable the prediction of elemental cycling under current and future climate scenarios.
We assembled communities of bacteria and exposed them to different nutrient concentrations with or without predation by protists. Taxa that were rare in the field were less abundant at low nutrient concentrations than common taxa, independent of predation. However, some taxa that were rare in the field became highly abundant in the assembled communities, especially under ample nutrient availability. This high abundance points at a possible competitive advantage of some rare bacterial taxa under nutrient-rich conditions. In contrast, the abundance of most rare bacterial taxa decreased at low resource availability. Since low resource availability will be the prevailing situation in most soils, our data suggests that under those conditions poor competitiveness for limiting resources may contribute to bacterial rarity. Interestingly, taxa that were rare in the field and most successful under predator-free conditions in the lab also tended to be more reduced by predation than common taxa. This suggests that predation contributes to rarity of bacterial taxa in the field. We further discuss whether there may be a trade-off between competitiveness and predation resistance. The substantial variability among taxa in their responses to competition and predation suggests that other factors, for example abiotic conditions and dispersal ability, also influence the local abundance of soil bacteria. This article is protected by copyright. All rights reserved.
Interactions between aboveground and belowground organisms are important drivers of plant growth and performance in natural ecosystems. Making practical use of such above-belowground biotic interactions offers important opportunities for enhancing the sustainability of agriculture, as it could favor crop growth, nutrient supply, and defense against biotic and abiotic stresses. However, the operation of above-and belowground organisms at different spatial and temporal scales provides important challenges for application in agriculture. Aboveground organisms, such as herbivores and pollinators, operate at spatial scales that exceed individual fields and are highly variable in abundance within growing seasons. In contrast, pathogenic, symbiotic, and decomposer soil biota operate at more localized spatial scales from individual plants to patches of square meters, however, they generate legacy effects on plant performance that may last from single to multiple years. The challenge is to promote pollinators and suppress pests at the landscape and field scale, while creating positive legacy effects of local plant-soil interactions for next generations of plants. Here, we explore the possibilities to improve utilization of above-belowground interactions in agro-ecosystems by considering spatio-temporal scales at which aboveground and belowground organisms operate. We identified that successful integration of above-belowground biotic interactions initially requires developing crop rotations and intercropping systems that create positive local soil legacy effects for neighboring as well subsequent crops. These configurations may then be used as building blocks to design landscapes that accommodate beneficial aboveground communities with respect to their required resources. For successful adoption of above-belowground interactions in agriculture there is a need for context-specific solutions, as well as sound socio-economic embedding.
DNA methylation is one of the mechanisms underlying epigenetic modifications. DNA methylations can be environmentally induced and such induced modifications can at times be transmitted to successive generations. However, it remains speculative how common such environmentally induced transgenerational DNA methylation changes are and if they persist for more than one offspring generation. We exposed multiple accessions of two different apomictic dandelion lineages of the Taraxacum officinale group (Taraxacum alatum and T. hemicyclum) to drought and salicylic acid (SA) treatment. Using methylation-sensitive amplified fragment length polymorphism markers (MS-AFLPs) we screened anonymous methylation changes at CCGG restriction sites throughout the genome after stress treatments and assessed the heritability of induced changes for two subsequent unexposed offspring generations. Irrespective of the initial stress treatment, a clear buildup of heritable DNA methylation variation was observed across three generations, indicating a considerable background rate of heritable epimutations. Less evidence was detected for environmental effects. Drought stress showed some evidence for accession-specific methylation changes, but only in the exposed generation and not in their offspring. By contrast, SA treatment caused an increased rate of methylation change in offspring of treated plants. These changes were seemingly undirected resulting in increased transgenerational epigenetic variation between offspring individuals, but not in predictable epigenetic variants. While the functional consequences of these MS-AFLP-detected DNA methylation changes remain to be demonstrated, our study shows that (1) stress-induced transgenerational DNA methylation modification in dandelions is genotype and context-specific; and (2) inherited environmental DNA methylation effects are mostly undirected and not targeted to specific loci.
Established theory addresses the idea that herbivory can have positive feedbacks on nutrient flow to plants. Positive feedbacks likely emerge from a greater availability of organic carbon that primes the soil by supporting nutrient turnover through consumer and especially microbially-mediated metabolism in the detrital pool. We developed an entirely novel stoichiometric model that demonstrates the mechanism of a positive feedback. In particular, we show that sloppy or partial feeding by herbivores increases detrital carbon and nitrogen allowing for greater nitrogen mineralization and nutritive feedback to plants. The model consists of differential equations coupling flows among pools of: plants, herbivores, detrital carbon and nitrogen, and inorganic nitrogen. We test the effects of different levels of herbivore grazing completion and of the stoichiometric quality (carbon to nitrogen ratio, C:N) of the host plant. Our model analyses show that partial feeding and plant C:N interact because when herbivores are sloppy and plant biomass is diverted to the detrital pool, more mineral nitrogen is available to plants because of the stoichiometric difference between the organisms in the detrital pool and the herbivore. This model helps to identify how herbivory may feedback positively on primary production, and it mechanistically connects direct and indirect feedbacks from soil to plant production.