85 research outputs found
Timing matters: Sampling frequency for early-warning indicators across food web components in a virtual lake
Shallow lakes are known for sudden shifts between a desired clear and an undesired turbid state despite only incremental changes in the underlying drivers. Such sudden shifts are a major challenge for lake managers who can be confronted with abrupt losses of desired ecosystem services without easily observable warning signals. Predictive tools for the loss of ecosystem resilience are vital to respond with timely mitigation measures and avert a shift to the undesired state. Early-warning indicators (EWIs) have faithfully preceded critical transitions in minimal models but have proven more elusive in real-world data, suggesting a mismatch between measurement strategy and the detectability of EWIs. Here, we capitalize on data simulated using the aquatic ecosystem model PCLake+ which represents real systems more closely than reductionistic models and which allows the generation of critical transitions in response to gradual changes in phosphorus load. We tested the effect of different sampling intervals (daily to yearly) on the detection of three often-used EWIs across a range of food web and nutrient-related variables. Moreover, we included one integrated sampling interval (yearly average of daily measurements) to represent time-integrated measurements. EWIs generally performed better at shorter intervals (daily, weekly) but integrated measurements over the year also proved suitable to detect oncoming state shifts. We propose that lake managers should aim for high-frequency measurements of variables that can be easily and cheaply measured (e.g. oxygen, Secchi) or, alternatively, focus on integrated approaches using passive samplers or sedimented material
Capturing elements of the Nature Futures Framework through in situ place descriptions:An empirical study in urban blue locations
Human-nature interaction is in constant flux, and capturing the present perceptions and imaginaries of urban nature could facilitate the development of scenarios that ensure positive futures for both nature and humans. This paper explores the feasibility of inferring and operationalizing the three key values of the Nature Futures Framework â Nature for Society, Nature as Culture, and Nature for Nature â through the language in place descriptions and place transformation suggestions, collected in situ in 57 urban blue spaces as part of a pilot citizen science project in the Netherlands. We suggest that cross-pollination between research working towards capturing place facets in natural discourse and the Nature Futures Framework has the potential to provide effective means for a better understanding and visualization of individual and collective nature-related values hold within communities in particular places, leading to transformations of urban nature in a way that is beneficial to both humans and nature
Process-based modeling for ecosystem service provisioning:Non-linear responses to restoration efforts in a quarry lake under climate change
Healthy freshwater ecosystems can provide vital ecosystem services (ESs), and this capacity may be hampered due to water quality deterioration and climate change. In the currently available ES modeling tools, ecosystem processes are either absent or oversimplified, hindering the evaluation of impacts of restoration measures on ES provisioning. In this study, we propose an ES modeling tool that integrates lake physics, ecology and service provisioning into a holistic modeling framework. We applied this model to a Dutch quarry lake, to evaluate how nine ESs respond to technological-based (phosphorus (P) reduction) and nature-based measures (wetland restoration). As climate change might be affecting the future effectiveness of restoration efforts, we also studied the climate change impacts on the outcome of restoration measures and provisioning of ESs, using climate scenarios for the Netherlands in 2050. Our results indicate that both phosphorus reduction and wetland restoration mitigated eutrophication symptoms, resulting in increased oxygen concentrations and water transparency, and decreased phytoplankton biomass. Delivery of most ESs was improved, including swimming, P retention, and macrophyte habitat, whereas the ES provisioning that required a more productive system was impaired (sport fishing and bird watching). However, our modeling results suggested hampered effectiveness of restoration measures upon exposure to future climate conditions, which may require intensification of restoration efforts in the future to meet restoration targets. Importantly, ESs provisioning showed non-linear responses to increasing intensity of restoration measures, indicating that effectiveness of restoration measures does not necessarily increase proportionally. In conclusion, the ecosystem service modeling framework proposed in this study, provides a holistic evaluation of lake restoration measures on ecosystem services provisioning, and can contribute to development of climate-robust management strategies.</p
Characterizing 19 thousand Chinese lakes, ponds and reservoirs by morphometric, climate and sediment characteristics
Chinese lakes, including ponds and reservoirs, are increasingly threatened by algal blooms. Yet, each lake is unique, leading to large inter-lake variation in lake vulnerability to algal blooms. Here, we aim to assess the effects of unique lake characteristics on lake vulnerability to algal blooms. To this end, we built a novel and comprehensive database of lake morphometric, climate and sediment characteristics of 19,536 Chinese lakes, including ponds and reservoirs (>0.1 km2). We assessed lake characteristics for nine stratification classes and show that lakes, including ponds and reservoirs, in eastern China typically have a warm stratification class (Tavg>4 °C) and are slightly deeper than those in western China. Model results for representative lakes suggest that the most vulnerable lakes to algal blooms are in eastern China where pollution levels are also highest. Our characterization provides an important baseline to inform policymakers in what regions lakes are potentially most vulnerable to algal blooms
Managing Successional Stage Heterogeneity to Maximize Landscape-Wide Biodiversity of Aquatic Vegetation in Ditch Networks
The presence of a high diversity of different successional stages in a landscape may help to conserve and promote landscape-wide biodiversity. A strategy to achieve this is using Cyclic Rejuvenation through Management (CRM), an approach employed in a variety of different ecosystems. CRM periodically resets the successional stages in a landscape. For aquatic systems this constitutes vegetation removal and dredging. For this approach to be useful (a) successional stages are required to be different in community composition and (b) these differences need to be caused by true replacement of species between stages. While potentially valid, these assumptions are not generally tested prior to application of CMR. In this study we test these assumptions to explore the usefulness of managing on successional stage heterogeneity for maximizing landscape-wide aquatic plant diversity. We carried out vegetation surveys in the ditch networks of 21 polder landscapes in Netherlands, each containing 24 ditch reaches. Using a clustering approach combined with insight from literature on vegetation succession in these systems we assigned our sampled communities to defined successional stages. After partitioning landscape diversity into its alpha and beta components, we quantified the relative importance of replacement among successional stages. Next, through scenario analyses based on simulations we studied the effects of reducing successional stage heterogeneity on landscape-wide biodiversity. Results showed that differences in community composition among successional stages were a potentially important factor contributing to landscape diversity. Early successional stages were characterized by higher replacement of species compared to late successional stages. In a scenario of gradual decrease of heterogeneity through the systematic loss of the earliest successional stages we found 20% of the species richness in a polder was lost, pointing toward the importance of maintaining early successional stages in a polder. This makes a compelling case for application of CRM within agricultural drainage ditch landscapes to maximize regional aquatic plant diversity. While applied to drainage ditch systems, our data-driven approach is broadly applicable to other systems and may help in providing first indications of the potential of the CRM approach. We argue that CRM may maintain and promote regional biodiversity without compromising the hydrological function of the systems
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. Graphical abstract: [Figure not available: see fulltext.]</p
A perspective on water quality in connected systems : modelling feedback between upstream and downstream transport and local ecological processes
Highlights
âą Catchment pollution limits water-related ecosystem services such as food production.
âą Water flow transports energy, substances and organisms downstream.
âą Organism behaviour causes bidirectional transport across the catchment.
âą Humans are modifiers of water and organismal transport.
âą Coupled transport-ecosystem models are essential for water quality assessment.Food production for a growing world population relies on application of fertilisers and pesticides on agricultural lands. However, these substances threaten surface water quality and thereby endanger valued ecosystem services such as drinking water supply, food production and recreational water use. Such deleterious effects do not merely arise on the local scale, but also on the regional scale through transport of substances as well as energy and biota across the catchment. Here we argue that aquatic ecosystem models can provide a process-based understanding of how these transports by water and organisms as vectors affect â and are affected by â ecosystem state and functioning in networks of connected lakes. Such a catchment scale approach is key to setting critical limits for the release of substances by agricultural practices and other human pressures on aquatic ecosystems. Thereby, water and food production and the trade-offs between them may be managed more sustainably
Stratification strength and light climate explain variation in chlorophyll a at the continental scale in a European multilake survey in a heatwave summer
To determine the drivers of phytoplankton biomass, we collected standardized morphometric, physical, and biological data in 230 lakes across the Mediterranean, Continental, and Boreal climatic zones of the European continent. Multilinear regression models tested on this snapshot of mostly eutrophic lakes (median total phosphorus [TP] = 0.06 and total nitrogen [TN] = 0.7 mgâLâ1), and its subsets (2 depth types and 3 climatic zones), show that light climate and stratification strength were the most significant explanatory variables for chlorophyll a (Chl a) variance. TN was a significant predictor for phytoplankton biomass for shallow and continental lakes, while TP never appeared as an explanatory variable, suggesting that under high TP, light, which partially controls stratification strength, becomes limiting for phytoplankton development. Mediterranean lakes were the warmest yet most weakly stratified and had significantly less Chl a than Boreal lakes, where the temperature anomaly from the long-term average, during a summer heatwave was the highest (+4°C) and showed a significant, exponential relationship with stratification strength. This European survey represents a summer snapshot of phytoplankton biomass and its drivers, and lends support that light and stratification metrics, which are both affected by climate change, are better predictors for phytoplankton biomass in nutrient-rich lakes than nutrient concentrations and surface temperature.Additional co-authors: Jolanda Verspagen, Maria van Herk, Maria G. Antoniou, Nikoletta Tsiarta, Valerie McCarthy, Victor C. Perello, Danielle Machado-Vieira, Alinne Gurjao de Oliveira, Dubravka Ć poljaric Maronic, Filip Stevic, Tanja Ćœuna Pfeiffer, Itana Bokan Vucelic, Petar Ćœutinic, Marija Gligora Udovic, AnÄelka Plenkovic-Moraj, Ludek Blaha, Rodan GeriĆĄ, MarkĂ©ta Frankova, Kirsten Seestern Christoffersen, Trine Perlt Warming, TĂ”nu Feldmann, Alo Laas, Kristel Panksep, Lea Tuvikene, Kersti Kangro, Judita Koreiviene, Jurate Karosiene, Jurate Kasperoviciene, Ksenija Savadova-Ratkus, Irma Vitonyte, Kerstin HĂ€ggqvist, Pauliina Salmi, Lauri Arvola, Karl Rothhaupt, Christos Avagianos, Triantafyllos Kaloudis, Spyros Gkelis, Manthos Panou, Theodoros Triantis, Sevasti-Kiriaki Zervou, Anastasia Hiskia, Ulrike Obertegger, Adriano Boscaini, Giovanna Flaim, Nico Salmaso, Leonardo Cerasino, Sigrid Haande, Birger Skjelbred, Magdalena Grabowska, Maciej Karpowicz, Damian Chmura, Lidia Nawrocka, Justyna Kobos, Hanna Mazur-Marzec, Pablo Alcaraz-Parraga, ElĆŒbieta Wilk-Wozniak, Wojciech Krzton, Edward Walusiak, Ilona Gagala-Borowska, Joana Mankiewicz-Boczek, Magdalena Toporowska, Barbara Pawlik-Skowronska, MichaĆ Niedzwiecki, Wojciech PÄczuĆa, Agnieszka Napiorkowska-Krzebietke, Julita Dunalska, Justyna Sienska, Daniel Szymanski, Marek Kruk, Agnieszka Budzynska, Ryszard Goldyn, Anna Kozak, Joanna Rosinska, ElĆŒbieta SzelÄ
g-Wasielewska, Piotr Domek, Natalia Jakubowska-Krepska, Kinga Kwasizur, Beata Messyasz, Aleksandra PeĆechata, Mariusz PeĆechaty, Mikolaj Kokocinski, Beata Madrecka-Witkowska, Iwona Kostrzewska-Szlakowska, Magdalena FrÄ
k, Agnieszka Bankowska-Sobczak, MichaĆ Wasilewicz, Agnieszka Ochocka, Agnieszka Pasztaleniec, Iwona Jasser, Ana M. Antao-Geraldes, Manel Leira, Vitor Vasconcelos, Joao Morais, Micaela Vale, Pedro M. Raposeiro, VĂtor Gonçalves, Boris Aleksovski, Svetislav Krstic, Hana Nemova, Iveta Drastichova, Lucia Chomova, Spela Remec-Rekar, Tina Elersek, Lars-Anders Hansson, Pablo Urrutia-Cordero, Andrea G. Bravo, Moritz Buck, William Colom-Montero, Kristiina Mustonen, Don Pierson, Yang Yang, Christine Edwards, Hannah Cromie, Jordi Delgado-MartĂn, David GarcĂa, Jose LuĂs Cereijo, Joan GomĂ , Mari Carmen Trapote, Teresa Vegas-VilarrĂșbia, Biel Obrador, Ana GarcĂa-Murcia, Monserrat Real, Elvira Romans, Jordi Noguero-Ribes, David Parreño Duque, ElĂsabeth Fernandez-Moran, Barbara Ăbeda, JosĂ© Angel Galvez, NĂșria Catalan, Carmen PĂ©rez-MartĂnez, EloĂsa Ramos-RodrĂguez, Carmen Cillero-Castro, Enrique Moreno-Ostos, JosĂ© MarĂa Blanco, Valeriano RodrĂguez, Jorge Juan Montes-PĂ©rez, Roberto L. Palomino, Estela RodrĂguez-PĂ©rez, Armand Hernandez, Rafael Carballeira, Antonio Camacho, Antonio Picazo, Carlos Rochera, Anna C. Santamans, Carmen Ferriol, Susana Romo, Juan Miguel Soria, Arda Ăzen, TĂŒnay Karan, Nilsun Demir, Meryem Beklioglu, Nur Filiz, Eti Levi, Ugur Iskin, Gizem Bezirci, ĂlkĂŒ Nihan Tavsanoglu, Kemal Ăelik, Koray Ozhan, Nusret Karakaya, Mehmet Ali Turan Koçer, Mete Yilmaz, Faruk Marasžlıoglu, Ăzden Fakioglu, Elif Neyran Soylu, Meral Apaydın Yagcı, Sakir Ăınar, Kadir Ăapkın, Abdulkadir Yagcı, Mehmet Cesur, Fuat Bilgin, Cafer Bulut, Rahmi Uysal, Köker Latife, Reyhan Akçaalan, Meriç Albay, Mehmet Tahir Alp, Korhan Ăzkan, Tugba Ongun Sevindik, Hatice Tunca, Burçin Ănem, Hans Paerl, Cayelan C. Carey, Bastiaan W. Ibeling
Exploring, exploiting and evolving diversity of aquatic ecosystem models: A community perspective
Here, we present a community perspective on how to explore, exploit and evolve the diversity in aquatic ecosystem models. These models play an important role in understanding the functioning of aquatic ecosystems, filling in observation gaps and developing effective strategies for water quality management. In this spirit, numerous models have been developed since the 1970s. We set off to explore model diversity by making an inventory among 42 aquatic ecosystem modellers, by categorizing the resulting set of models and by analysing them for diversity. We then focus on how to exploit model diversity by comparing and combining different aspects of existing models. Finally, we discuss how model diversity came about in the past and could evolve in the future. Throughout our study, we use analogies from biodiversity research to analyse and interpret model diversity. We recommend to make models publicly available through open-source policies, to standardize documentation and technical implementation of models, and to compare models through ensemble modelling and interdisciplinary approaches. We end with our perspective on how the field of aquatic ecosystem modelling might develop in the next 5â10Â years. To strive for clarity and to improve readability for non-modellers, we include a glossary
Modeling water quality in the Anthropocene : directions for the next-generation aquatic ecosystem models
âEverything changes and nothing stands stillâ (Heraclitus). Here we review three major improvements to freshwater aquatic ecosystem models â and ecological models in general â 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.
Highlights
âą We present a research agenda to enhance water quality modeling in the Anthropocene.
âą We review adaptive responses in organisms and ecosystems to global environmental change.
âą We focus on eco-evolutionary, novel ecosystem and social-ecological dynamics.
âą These dynamics act at different integration levels and different time scales.
âą Lake Victoria is an iconic example of an evolving novel social-ecological system
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