Droevendaalsesteeg 10
6708 PB Wageningen
The Netherlands
About
During my PhD project at NIOO-KNAW and Wageningen University I will explore the potential of the new concept of Smart Nutrient Retention Networks to improve water quality and sustainable nutrient use.
Biography
The underlying societal problem that I aim to address in this project is that nutrients end up in surface waters, where they cause water quality problems (e.g. harmful algal blooms) and eventually are lost into the ocean where they become unavailable to humanity. The idea is that positive feedback mechanisms between water plants and nutrient retention in individual waterbodies can affect water quality of larger hydrological networks. In my project, I will develop a model to test and demonstrate smart management strategies to retain and recycle nutrients locally, whilst improving water quality at a larger scale.
Research groups
CV
Publications
Key publications
Smart Nutrient Retention Networks: a novel approach for nutrient conservation through water quality management
Nutrients are essential resources for food production but are used inefficiently, and thereby they pollute inland and coastal waters and are lost into the oceans. Nutrient conservation by retention and consecutive reuse would prevent nutrient losses to the atmosphere and downstream ecosystems. We present Smart Nutrient Retention Networks (SNRNs) as a novel management approach to achieve nutrient conservation across networks of connected waterbodies through strategic water quality management. To present the key features of SNRNs, we review existing knowledge of nutrient retention processes in inland waters, water quality management options for nutrient conservation, and nutrient retention models to develop SNRNs. We argue that successful nutrient conservation, even at a local level, through SNRN management strategies requires clearly formulated goals and catchment-wide system understanding. Waterbody characteristics, such as hydraulic residence time and the presence of macrophytes, shape local nutrient retention with potential network-wide cascading effects of improved water quality and are therefore key targets of SNRN management strategies. Nutrient retention models that include the self-reinforcing feedback loop of ecological water quality, nutrient retention, and nutrient loading in networks of inland waters in relation to management options can support the development of SNRNs. We conclude that SNRNs can contribute to sustainable use of nutrients in human food production.
Peer-reviewed publications
Connecting lakes: Modeling flows and interactions of organisms and matter throughout the waterscape
Eutrophication poses a threat to lake ecosystem services provisioning worldwide. When eutrophic lakes are connected to other water systems, either through water flows, or through organismal movement and dispersal, their excess nutrients affect nearby lakes too. Understanding nutrient transport dynamics in lake meta-ecosystems is not trivial, as it encompasses the complexity of ecosystems themselves (i.e., food web dynamics, nutrient cycling) and the transport between ecosystems. Hitherto, it remains unknown how heterogeneity in lake meta-ecosystems affects their ecological resilience. We argue that scientists and water managers would benefit from the use of meta-ecosystem models while unravelling meta-ecosystem complexity. To this end, we converted lake ecosystem model PCLake+ into lake meta-ecosystem model PCLakeS+. We showed that the spatial configuration of a lake meta-ecosystem influences its ecological dynamics, and that nutrient transport depends heavily on food web processes. We conclude that PCLakeS+ is suitable for exploring meta-ecosystem concepts for science and water management.https://doi.org/10.1016/j.envsoft.2023.105765Regime shifts in shallow lakes explained by critical turbidity
https://doi.org/10.1016/j.watres.2023.119950Worldwide, water quality managers target a clear, macrophyte-dominated state over a turbid, phytoplankton-dominated state in shallow lakes. The competition mechanisms underlying these ecological states were explored in the 1990s, but the concept of critical turbidity seems neglected in contemporary water quality models. In particular, a simple mechanistic model of alternative stable states in shallow lakes accounting for resource competition mechanisms and critical turbidity is lacking. To this end, we combined Scheffer's theory on critical turbidity with insights from nutrient and light competition theory founded by Tilman, Huisman and Weissing. This resulted in a novel graphical and mathematical model, GPLake-M, that is relatively simple and mechanistically understandable and yet captures the essential mechanisms leading to alternative stable states in shallow lakes. The process-based PCLake model was used to parameterize the model parameters and to test GPLake-M using a pattern-oriented strategy. GPLake-M's application range and position in the model spectrum are discussed. We believe that our results support the fundamental understanding of regime shifts in shallow lakes and provide a starting point for further mechanistic and management-focused explorations and model development. Furthermore, the concept of critical turbidity and the relation between light-limited submerged macrophytes and nutrient-limited phytoplankton might provide a new focus for empirical aquatic ecological research and water quality monitoring programs.
New paths for modelling freshwater nature futures
Freshwater ecosystems are exceptionally rich in biodiversity and provide essential benefits to people. Yet they are disproportionately threatened compared to terrestrial and marine systems and remain underrepresented in the scenarios and models used for global environmental assessments. The Nature Futures Framework (NFF) has recently been proposed to advance the contribution of scenarios and models for environmental assessments. This framework places the diverse relationships between people and nature at its core, identifying three value perspectives as points of departure: Nature for Nature, Nature for Society, and Nature as Culture. We explore how the NFF may be implemented for improved assessment of freshwater ecosystems. First, we outline how the NFF and its main value perspectives can be translated to freshwater systems and explore what desirable freshwater futures would look like from each of the above perspectives. Second, we review scenario strategies and current models to examine how freshwater modelling can be linked to the NFF in terms of its aims and outcomes. In doing so, we also identify which aspects of the NFF framework are not yet captured in current freshwater models and suggest possible ways to bridge them. Our analysis provides future directions for a more holistic freshwater model and scenario development and demonstrates how society can benefit from freshwater modelling efforts that are integrated with the value-perspectives of the NFF.https://doi.org/10.1007/s11625-023-01341-0Nationaal Park 3.0
Protected areas are the cornerstone of nature conservation, although this approach has not prevented the current biodiversity crisis. In addition, the approach leads to the suggestion that only organisms living within these areas constitute nature. Nature, however, cannot be spatially constrained, and the same holds for human influence on nature. In this essay we develop an area-wide and human-inclusive vision of nature conservation into a new approach for national parks that we call National Park 3.0 (NP 3.0). The concept is rooted in a re-evaluation of human-nature relations sensu the Nature Futures Framework developed under IPBES. Moreover, we note that ‘landscape’ has always been a social-ecological concept since the term was coined by 17th century Dutch painters. Finally, we note that nature and human infrastructure are deeply entangled at multiple spatial scales in modern landscapes. We define NP 3.0 spatially by the contours of a landscape that is recognizable by people and has geomorphological and ecological coherence. We relate NP 3.0 to other initiatives for restoring biodiversity and provide a conceptual design for NP 3.0. Throughout this essay we use Nationaal Park Hollandse Duinen as a case study where NP 3.0 is worked out in practice.Smart Nutrient Retention Networks
Nutrients are essential resources for food production but are used inefficiently, and thereby they pollute inland and coastal waters and are lost into the oceans. Nutrient conservation by retention and consecutive reuse would prevent nutrient losses to the atmosphere and downstream ecosystems. We present Smart Nutrient Retention Networks (SNRNs) as a novel management approach to achieve nutrient conservation across networks of connected waterbodies through strategic water quality management. To present the key features of SNRNs, we review existing knowledge of nutrient retention processes in inland waters, water quality management options for nutrient conservation, and nutrient retention models to develop SNRNs. We argue that successful nutrient conservation, even at a local level, through SNRN management strategies requires clearly formulated goals and catchment-wide system understanding. Waterbody characteristics, such as hydraulic residence time and the presence of macrophytes, shape local nutrient retention with potential network-wide cascading effects of improved water quality and are therefore key targets of SNRN management strategies. Nutrient retention models that include the self-reinforcing feedback loop of ecological water quality, nutrient retention, and nutrient loading in networks of inland waters in relation to management options can support the development of SNRNs. We conclude that SNRNs can contribute to sustainable use of nutrients in human food production.https://doi.org/10.1080/20442041.2020.1870852A generically parameterized model of Lake eutrophication
https://doi.org/10.1016/j.ecolmodel.2022.110142Water quality improvement to avoid excessive phytoplankton blooms often requires eutrophication management where both phosphorus (P) and nitrogen (N) play a role. While empirical eutrophication studies and ecological resource competition theory both provide insight into phytoplankton abundance in response to nutrient loading, they are not seamlessly linked in the current state of eutrophication research. We argue that understanding species competition for multiple nutrients and light in natural phytoplankton communities is key to assessing phytoplankton abundance under changing nutrient supply. Here we present GPLake-S, a mechanistic model rooted in ecological resource competition theory, which has only eight parameters and can predict chlorophyll-a to nutrient relationships for phytoplankton communities under N, P, N+P colimitation and light limitation. GPLake-S offers a simple mechanistic tool to make first estimates of chlorophyll-a levels and nutrient thresholds for generic lake properties, accounting for variation in N:P ratio preferences of phytoplankton species. This makes the model supportive of water management and policy.
Exploring desirable nature futures for Nationaal Park Hollandse Duinen
Achieving global sustainability goals requires most people and societies to fundamentally revisit their relationship with nature. New approaches are called for to guide change processes towards sustainable futures that embrace the plurality of people’s desired relationships with nature. This paper presents a novel approach to exploring desirable futures for nature and people that was developed through an application in Nationaal Park Hollandse Duinen in the Netherlands. This new national park is developed bottom-up by a diverse group of actors reshaping their interactions with each other and with nature. Our approach, co-designed with key stakeholders of the national park, engages with a new pluralistic framework for human-nature relationships presented by the IPBES task force on scenarios and models to catalyze the development of nature-centered scenarios. We integrated this Nature Futures Framework with the Three Horizons Framework in a participatory workshop process designed to bring people’s diverse relationships with nature to the fore, and jointly envision desirable futures and the pathways to get there. We present a methodology to analyze and compare the visions and assess their potential contribution to the SDGs. We summarize the results of the application in Nationaal Park Hollandse Duinen and reflect on lessons learned. The approach successfully engaged participants in joint exploration of desirable futures for the national park based on their plural perspectives on human-nature relationships. We see much potential for its applications to support change processes in various social-ecological contexts toward more sustainable futures for nature and people.https://doi.org/10.1080/26395916.2022.2065360Flipping Lakes: Explaining concepts of catchment-scale water management through a serious game
Ongoing anthropogenic and climatic pressures on inland waters have made water quality management a challenge of the 21st century. A holistic catchment-scale approach to water management which includes stakeholder participation will be a key in maintaining lake health. A first step toward community engagement is to bolster environmental literacy on lake management, ecology, and eutrophication concepts of stakeholders now and in future generations. However, communicating with nonwater professionals about effects of pollution on water quality and catchment-scale interactions across space and time can be difficult. Here, we present “Flipping Lakes,” a games-based method for lake professionals to communicate and educate about catchment-level water quality management to diverse audiences. In Flipping Lakes, the players take on the role of water managers in a catchment and are tasked to prevent a lake from “flipping” from a clear to a turbid state. During the game, the catchment slowly becomes polluted by a range of sources of which the effects are exacerbated by societal or climatic scenarios. Players need to implement measures while taking into consideration the intrinsic properties of the catchment in order to keep lakes clean. The game was tested with a diverse range of user groups and was well-received. With its entertaining and accessible content, Flipping Lakes can lower communication barriers and increase understanding of difficult water quality concepts. The game is highly customizable, making it applicable to a variety of settings to support education and engagement of stakeholders and the broader community in order to address local water challenges around the globe.https://doi.org/10.1002/lom3.10436How to model algal blooms in any lake on earth
Algal blooms increasingly threaten lake and reservoir water quality at the global scale, caused by ongoing climate change and nutrient loading. To anticipate these algal blooms, models to project future algal blooms worldwide are required. Here we present the state-of-the-art in algal projection modelling and explore the requirements of an ideal algal projection model. Based on this, we identify current challenges and opportunities for such model development. Since most building blocks are present, we foresee that algal projection models for any lake on earth can be developed in the near future. Finally, we think that algal bloom projection models at a global scale will provide a valuable contribution to global policymaking, in particular with respect to SDG 6 (clean water and sanitation).https://doi.org/10.1016/j.cosust.2018.09.001A generically parameterized model of Lake eutrophication (GPLake) that links field-, lab- and model-based knowledge
Worldwide, eutrophication is threatening lake ecosystems. To support lake management numerous eutrophication models have been developed. Diverse research questions in a wide range of lake ecosystems are addressed by these models. The established models are based on three key approaches: the empirical approach that employs field surveys, the theoretical approach in which models based on first principles are tested against lab experiments, and the process-based approach that uses parameters and functions representing detailed biogeochemical processes. These approaches have led to an accumulation of field-, lab- and model-based knowledge, respectively. Linking these sources of knowledge would benefit lake management by exploiting complementary information; however, the development of a simple tool that links these approaches was hampered by their large differences in scale and complexity. Here we propose a Generically Parameterized Lake eutrophication model (GPLake) that links field-, lab- and model-based knowledge and can be used to make a first diagnosis of lake water quality. We derived GPLake from consumer-resource theory by the principle that lacustrine phytoplankton is typically limited by two resources: nutrients and light. These limitations are captured in two generic parameters that shape the nutrient to chlorophyll-a relations. Next, we parameterized GPLake, using knowledge from empirical, theoretical, and process-based approaches. GPLake generic parameters were found to scale in a comparable manner across data sources. Finally, we show that GPLake can be applied as a simple tool that provides lake managers with a first diagnosis of the limiting factor and lake water quality, using only the parameters for lake depth, residence time and current nutrient loading. With this first-order assessment, lake managers can easily assess measures such as reducing nutrient load, decreasing residence time or changing depth before spending money on field-, lab- or model- experiments to support lake management.https://doi.org/10.1016/j.scitotenv.2019.133887Modeling water quality in the Anthropocene: Directions for the next-generation aquatic ecosystem models
“Everything changes and nothing stands still” (Heraclitus). Here we review three major improvements to freshwater aquatic ecosystem models — and ecological models in general — as water quality scenario analysis tools towards a sustainable future. To tackle the rapid and deeply connected dynamics characteristic of the Anthropocene, we argue for the inclusion of eco-evolutionary, novel ecosystem and social-ecological dynamics. These dynamics arise from adaptive responses in organisms and ecosystems to global environmental change and act at different integration levels and different time scales. We provide reasons and means to incorporate each improvement into aquatic ecosystem models. Throughout this study we refer to Lake Victoria as a microcosm of the evolving novel social-ecological systems of the Anthropocene. The Lake Victoria case clearly shows how interlinked eco-evolutionary, novel ecosystem and social-ecological dynamics are, and demonstrates the need for transdisciplinary research approaches towards global sustainability.https://doi.org/10.1016/j.cosust.2018.10.012Towards a global model for wetlands ecosystem services
Wetlands play an important role in the provision of important ecosystem services like the provision of clean water to the world, adaptation to climate change, and support for biodiversity; although they are sometimes also associated with adverse climate effects. Wetlands are, however, currently grossly underrepresented in global environmental models. In this paper, we explore the required functionality of a generic model of the effects of climate and land-use changes on wetlands ecosystem services worldwide. We briefly review existing models to identify elements which can be combined to compile a generic wetland model. The proposed global wetland model should be integrated into and receive data from existing hydrology and climate models. Wetland delineation can be based on local hydrological and topographical conditions and verified with global wetland databases. We conclude that an integrated approach combining hydrology, biogeochemistry and vegetation for wetlands is not available yet, however, useful building blocks exist that can be combined.https://doi.org/10.1016/j.cosust.2018.09.002Success of lake restoration depends on spatial aspects of nutrient loading and hydrology
Many aquatic ecosystems have deteriorated due to human activities and their restoration is often troublesome. It is proposed here that the restoration success of deteriorated lakes critically depends on hitherto largely neglected spatial heterogeneity in nutrient loading and hydrology. A modelling approach is used to study this hypothesis by considering four lake types with contrasting nutrient loading (point versus diffuse) and hydrology (seepage versus drainage). By comparing the longterm effect of common restoration measures (nutrient load reduction, lake flushing or biomanipulation) in these four lake types, we found that restoration through reduction of nutrient loading is effective in all cases. In contrast, biomanipulation only works in seepage lakes with diffuse nutrient inputs, while lake flushing will even be counterproductive in lakes with nutrient point sources. The main conclusion of the presented analysis is that a priori assessment of spatial heterogeneity caused by nutrient loading and hydrology is essential for successful restoration of lake ecosystems.https://doi.org/10.1016/j.scitotenv.2019.04.443