In recent years, several valuable biodiversity time series data have successfully been mobilized and published in accessible repositories (e.g., BioTime), resulting in substantial improvements in our understanding of biodiversity change in the Anthropocene. Yet, there are still huge data and knowledge gaps, particularly in functional changes and notoriously understudied taxonomic groups like insects and fungi. Additionally, biodiversity monitoring is still insufficiently co-located with in situ measurements of ecosystem functions, environmental drivers, and social-economic implications, including nature’s contributions to people. Recent research infrastructures, including eLTER (https://elter-ri.eu/) and NEON (https://www.neonscience.org/), have started filling in these gaps.
This session aims to bring together biodiversity researchers, environmental monitoring experts, including larger research infrastructures, authorities, and NGOs. We seek contributions addressing:
• multi-decadal changes in biodiversity, ecosystem functions, and their drivers at local, regional, or global scales covering marine, freshwater or terrestrial ecosystems
• improved statistical methods to measure trends and link to associated drivers
• social-economic implications of biodiversity change
• potential ways forward to overcome current data limitations in the dimension, drivers and consequences of biodiversity change and impacts on functions in the Anthropocene.
To understand biodiversity change in response to anthropogenic stressors, the idea of critical biodiversity transitions is a prevailing framework. It has been especially prominent in the literature of regime shifts, where a new regime is associated with a different biodiversity. A classical tipping point is defined as the threshold where a minor change in a driver or pressure level leads to an abrupt, disproportionate change in the response variable and the system transitions into a new regime. However, applying this framework to biodiversity presents a challenge: it remains unclear whether and how biodiversity ‘tips,’ and to what extent current detection methods are useful for capturing potential, multi-dimensional biodiversity state shifts. In this work, we conduct a systematic literature review to identify the most common approaches to detecting critical transitions in ecology. We specifically focus on studies analysing transitions in species and species assemblages. We review the current literature between 2020 and 2024 to assess the applied detection methods, their characteristics, advantages and limitations, and underlying concepts. Firstly, our analysis reveals conceptual confusion: terminology (e.g., 'tipping point,' 'regime shift,' 'threshold') is often used interchangeably, and many publications lack clear definitions of the terms and the specific ecological phenomenon under study. This conceptual ambiguity potentially impacts communication and comparison of results across studies. Analysing the characteristics of the different concepts, we show that most detection approaches are not sufficient to capture the complexity of biodiversity change, and they often rely on dimensionality reduction and analysis of subsystems. We argue that a clear definition of the phenomenon under study is urgently needed, and a cautious and critical interpretation of the results is necessary. We discuss methodological needs towards improved transition detection and call for a shift in perspective, with more focus on considering alternative hypotheses to understand biodiversity change rather than solely on threshold transgressions.
How to cite: Luhede, A., Gross, T., and Hillebrand, H.: Approaches towards the detection of critical biodiversity transitions, World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-814, https://doi.org/10.5194/wbf2026-814, 2026.
Maintaining biodiversity is central to the sustainable development agenda, However, a lack of context-specific biodiversity information at policy-relevant scales has posed major limitations to decision-makers. To address this challenge, we undertook a comprehensive assessment of the biodiversity intactness of sub-Saharan Africa using place-based knowledge of 200 African biodiversity experts. Our bottom-up approach overcomes critical data gaps and limitations of top-down biodiversity models by quantifying biodiversity intactness using the Biodiversity Intactness Index for Africa (bii4africa), a dataset that we previously co-produced and published with 200 experts in African fauna and flora. These experts embody place-based African biodiversity knowledge, which holds credibility, legitimacy and saliency for mainstreaming into national decision-making and contributes to inclusivity and decoloniality in science. The bii4africa dataset contains standardized estimates by experts of the impact of the predominant land uses in sub-Saharan Africa on diverse functional groupings of species that represent around 50,000 terrestrial vertebrates and vascular plants. Here we integrate ten spatial datasets to map these land uses, which we combine with bioregional lists of indigenous taxa and the associated bii4africa data to map the BII across sub-Saharan Africa. We estimate that the region has on average lost 24% of its pre-colonial and pre-industrial faunal and floral population abundances, ranging from losses of <20% for disturbance-adapted herbaceous plants to 80% for some large mammals. Rwanda and Nigeria are the least intact (<55%), whereas Namibia and Botswana are the most intact (>85%). Notably, most remaining organisms occur in unprotected, relatively untransformed rangelands and natural forests. Losses in biodiversity intactness in the worst-affected biomes are driven by land transformation into cropland in grasslands and fynbos (Mediterranean-type ecosystems), by non-agricultural degradation in forests and by a combination of the two drivers in savannas. This assessment provides decision-makers with multifaceted, contextually appropriate and policy-relevant information on the state of biodiversity in an understudied region of the world. Our approach could be used in other regions, including better-studied localities, to integrate contextual, place-based knowledge into multiscale assessments of biodiversity status and impacts.
How to cite: Clements, H., Biggs, R., and De Vos, A. and the Biodiversity Intactness Index for Africa Project: A place-based assessment of biodiversity intactness in sub-Saharan Africa, World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-837, https://doi.org/10.5194/wbf2026-837, 2026.
We are currently witnessing a mass extinction crisis due to increasingly overwhelming human impacts on the biosphere. Extinctions from the last few hundred years have been well-known for some taxonomic groups, but represent only the tip of the iceberg. While there is accumulating evidence that the number of historic human-induced extinctions is far higher than documented in the ‘gold standard’ for assessing extinction risks - the IUCN Red List - the extent and characteristics of poorly documented or ‘dark extinctions’ remain insufficiently known. Such dark extinctions, which are preceded by undocumented local declines and extinctions, have profound implications for assessing long-term trajectories of biodiversity change of local assemblages.
Dark extinctions and undocumented local species declines span a gradient from events that left no direct trace, to documented losses supported by substantial evidence (e.g., subfossil remains, ancient DNA, historic descriptions, specimens in herbaria or museums, observation records) waiting to be formally accepted as actual local decline or extinction by rigorous scientific standards. Here, we synthesize the state of knowledge on the discrepancy between documented and dark extinctions, and assess the implications of undocumented local species losses on biodiversity assessments. We identify six essential dimensions for Red List assessments, and we provide an assessment of their coverage in the IUCN Red List. To this end we review the evidence on how extinction drivers have changed in importance over time, and how well they are actually covered by Red List assessments. We identify ten sources of gaps and biases in documenting extinctions and local species losses and evaluate the role of temporal lags in these processes. We discuss the implications of these findings for studying species richness and the temporal dynamics of local assemblages, and more broadly, for assessing the true scale of the unfolding extinction crisis and assess the implications for conservation policy. Finally, we identify key steps to better account for undocumented species declines from local to global scales.
How to cite: Essl, F., Dullinger, S., Rabitsch, W., Burns, K., Foufopoulos, J., Hulme, P., Jaric, I., Katsanevakis, S., Ladle, R., Russell, J., Svenning, J.-C., Wood, J., and Lenzner, B.: Dark extinctions in a rapidly changing world, World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-371, https://doi.org/10.5194/wbf2026-371, 2026.
Biodiversity is changing in ecosystems worldwide, but assessing the true magnitude of this transformation requires the analysis of multiple dimensions of compositional change. Assessments often focus on single indicator types or metrics, but here we show that there is very limited correlation between different dimensions of transformation. Our example are the extensive monitoring data from the Wadden Sea UNESCO world heritage site (26560 unique samples distributed across 37 monitoring programs with 455 stations total). We simultaneously analyze trends in population sizes, annual (alpha) diversity, temporal turnover in composition (between subsequent years and with increasing temporal distance), and temporal changes in spatial (beta) diversity across different Hill numbers. Time series with increasing and decreasing alpha diversity were roughly equally abundant, with notable exceptions for plants and zoobenthos (more negative trends) as well as phytoplankton (more positive trends). Turnover in species composition between subsequent years was high, but showed only subtle signs of acceleration or deceleration over time. However, with larger temporal distance, dissimilarity increased to the extent that at least 15% of the time series effectively replaced the community composition at least once. Almost all organism groups showed increased spatial beta-diversity over time, thus, we found no signs of biotic homogenization between locations. In summary, the biodiversity of the Wadden Sea has been transformed substantially, but with little synchrony between organism groups in terms of phases of rapid and slow changes. The dimensionality of these shifts becomes only evident when simultaneously addressing multiple facets of biodiversity ranging from local alpha diversity to the cumulative turnover in time and space. None of these metrics alone would be able to indicate the amount of change, as each captures a different facet. To convert these issues into meaningful actions, we need to even extend beyond the quantitative assessment of biodiversity change and its functional consequences by including human values and emotions as an integral part of biodiversity reporting.
How to cite: Hillebrand, H. and the Wadden Sea Data Team: Multidimensional assessment of biodiversity change reveals substantial transformation across taxonomic groups , World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-209, https://doi.org/10.5194/wbf2026-209, 2026.
Over the past decades, environmental conditions in freshwater ecosystems have largely improved in the global north as consequence of the implementation of environmental regulations, resulting in a higher ecological status of streams and rivers. Although a recovery of the aquatic communities has been recently reported, it still remains unclear whether the improvement of these conditions has also restored the underlying biodiversity patterns. In natural systems, biodiversity is shaped by spatial and environmental gradients, but human pressures tend to disrupt these relationships. Typically, the composition of biological communities decrease in similarity with increasing geographical distance due to environmental differences between sites and the dispersal limitations of organisms; a biogeographical pattern known as distance decay. Anthropogenic impacts can further alter this pattern and temporal fluctuations in environmental conditions can also lead to varying rates of distance-decay in community similarity. Here, we aim at understanding the variation of continental scale community structure and composition over the last decades by analyzing the decay in similarity between communities with increasing geographical distance. We hypothesize that communities have become more homogeneous, both taxonomically and functionally, through time due to the improvement of environmental conditions, leading to a shallower decay in similarity over time. For this purpose, we collected publicly available data of fish monitoring surveys from five different European countries for the last 20 years. For each year, we calculated taxonomic and functional distance between communities, as well as geographic distance between sampling sites. We additionally obtained environmental information such as flow connection, climatic region and human footprint index for each site. We used a hierarchical Bayesian model approach to determine how community similarity was associated to the variables of interest and how distance decay changed with time. Preliminary results suggest that the relationship between community similarity and geographic distance changes over time, although the effects of human impact are still obvious.
How to cite: de Guzman Martinez, M. I., Buoro, M., and Larrañaga Arrizabalaga, A.: Linking distance with community composition: long-term trends in distance decay in freshwaters, World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-688, https://doi.org/10.5194/wbf2026-688, 2026.
To understand the future of forests, we must have a detailed understanding of past changes due to climate and land use change. And woody encroachment can have important consequences for carbon stocks and mountain biodiversity. The abandonment of agricultural activities results in woody encroachment, converting species rich mosaic habitats like dry meadows, bogs, and fens into expanding forested areas. These habitats, which are particularly important for biodiversity conservation in Switzerland, face imminent threats. Woody vegetation encroachment not only alters habitat structure but also can drive declines in vascular plant species due to associated effects, such as increased shading or altered competition. We quantify cover and height of woody plants in Switzerland during a 40-year period. Our data are based on a high-resolution Vegetation Height Model (VHM) with 1 meter resolution for four time steps between 1979 and 2020. Our research addresses this complex relationship by utilizing 40 years of high-resolution vegetation height data (1 meter) across Switzerland. For plant biodiversity data, we use a comprehensive dataset comprising over 4,000 vegetation surveys from the effectiveness of habitat conservation monitoring (WBS) in Switzerland. We find that although the greatest increases of woody shrub encroachment are occurring along the southern Alps in Ticino and Graubünden, it is also occurring in habitats in the central and northern Alps at a slower pace. We see both infilling with trees in already existing semi-open forest landscapes as well as upward tree and shrub migration at and above treeline. We found this has significant consequences on habitats of conservation concern, where plant species diversity decreases even at the initial stages of encroachment. When plots contained tree species even less than 0.5 m tall, plant species richness was 50% lower than in plots without tree species. By analyzing the drivers and consequences of agricultural abandonment, our project aims to offer scientific insights for mitigating the adverse impacts on biodiversity associated with land use changes.
How to cite: Rixen, C., Shipley, R., Frey, E., Bergamini, A., and Ginzler, C.: Fine-scale tree cover changes in Switzerland in 40 years and their impacts on plant biodiversity, World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-826, https://doi.org/10.5194/wbf2026-826, 2026.
Land-use changes, including expansion and intensification, are among the main drivers of biodiversity change in terrestrial ecosystems. However, an ecosystem perspective, particularly in tropical ecosystems, is limited because we still lack knowledge of the consequences of above- and belowground diversity and their interactions. This gap is the result of most studies focusing mainly on aboveground diversity or examining effects on these compartments separately.
To reach an ecosystem-wide perspective on the effects of land use on tropical biodiversity, we suggest a framework that first accounts for the historical perspective on human-environmental relationships, from deep time to recent land-use history. Second, our framework suggests integrating the biogeographic context in which land-use changes occur, as it defines the biotic and abiotic arena in which the species interact and potentially shape their responses to anthropogenic pressures. Third, as biodiversity goes beyond the number of species and affects multiple biological and spatial scales, we explore other facets of biodiversity that can be affected, with a special focus on biotic interactions. We also integrated cross-biological-organization impacts, from individuals to metacommunities, into our framework, offering a basis for assessing the patterns and rates of biodiversity changes and underlying mechanisms across spatial scales. Across our framework, we consider potential mismatches across taxonomic groups. These mismatches are hypothesized as growing evidence suggests non-coordinated responses between the above and belowground compartments. We use examples from our own collaborative research, including biodiversity hotspots such as Indonesia and Madagascar, and complement them with a selection of studies from the literature. This selection was primarily based on their inclusion of multiple taxonomic groups covering the above- and below-ground compartments in the tropics.
Our framework aims to highlight the relevance of considering both above- and below-ground biodiversity to meet international biodiversity targets. This is pivotal for conservation and ecosystem restoration targets in an era of rapid anthropogenic change. We also expect this framework to contribute to the development of a roadmap for a more inclusive, ecosystem-wide perspective on land-use impacts on tropical biodiversity.
How to cite: Zemp, D. C. and Guerrero Ramirez, N.: An ecosystem-wise perspective of land-use change impacts on above and belowground tropical biodiversity, World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-801, https://doi.org/10.5194/wbf2026-801, 2026.
A stable Earth system requires a healthy biosphere, but many ecosystems are being pushed beyond safe limits due to human activities such as land-use change, resource extraction, or climatic changes. Functional biosphere integrity is at the core of global assessments demarcating the limits to this human interference with our planet (Richardson et al. 2023, Rockström et al. 2023, te Wierik et al. 2025).
Studying the biosphere can happen through field observations, remote sensing, or computer models. Modelling has the advantage of obtaining global scale data, and the opportunity to also study past and future states of the Earth System.
We utilize the dynamic global vegetation model LPJmL to map the pressures of climate change and land use on ecosystems via the two indicators human appropriation of net primary productivity (HANPP) and the risk for ecosystem destabilization (EcoRisk) spatially explicitly for each year since 1600 (Stenzel et al. 2025). HANPP acts as a metric for human pressure on the environment, while EcoRisk is more of a response metric measuring changes in biogeochemical conditions and thus risk for degradation.
Since such indicators ideally also require thresholds that define when local boundaries are breached, we developed a method using 10 independent indicators for biosphere integrity (e.g. human footprint index, biodiversity intactness index, forest landscape integrity index) informing where local transgressions have already occurred. This helped us to map regions with intermediate and high risk of degradation and allowed us to aggregate the local status to the area globally transgressing the local boundaries.
Both metrics show strongly increasing values since 1600, and combined are current transgressed on 60% of the land area, with 38% already at high risk.
A preliminary assessment of the future status according to simulations from ISIMIP3b scenarios indicates that climatic pressures will keep rising, while pressures due to land use change strongly vary with scenario, based on projected productivity changes on agricultural areas and the demand for bioenergy plantations as a negative emissions technology.
How to cite: Stenzel, F., Priesner, J., Gerten, D., and Lucht, W.: Mapping functional biosphere integrity via human appropriated NPP and ecosystem change, World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-627, https://doi.org/10.5194/wbf2026-627, 2026.
Re-survey and monitoring studies have demonstrated that species numbers on European mountaintops have been rising over the recent decades, and that this increase is most likely driven by the warming climate. However, to what extent rising species numbers are the result of a balance that also involves losers, and whether there are specific features that characterize these losers, remains elusive. Here, we use data from four consecutive surveys of the GLORIA Europe long-term monitoring project to analyse species’ local extinction rates in the period 2001 – 2022 at 900 1 m² plots distributed across 62 mountaintops situated in 16 different European mountain ranges that span a gradient from Mediterranean to boreal biomes. We find that, on average across all 900 plots, 21% of the species recorded on a plot in 2001 were not redetected in the same plot in 2022. Local extinctions have occurred in all three re-surveys (2008, 2015, 2022), but the frequency of these extinctions has increased over time, as well as with greater magnitude of climate warming. Simultaneously, the total number of species per plot and mountaintop as well as total vegetation cover have also increased over time. Species adapted to cooler conditions than the average other species found on a particular plot or summit in 2001 were more likely to disappear from a plot or summit in the subsequent resurveys. Local extinction from a plot in one survey was moreover significantly correlated with a decline in abundance in the preceding monitoring period, and even more so with a continuous decline in the two preceding monitoring periods, indicating that a steady decline is an early warning signal of eventual disappearance, despite considerable abundance fluctuations across all species and plots. These findings demonstrate that increasing total plant species richness and vegetation cover of high-elevation plant assemblages mask an accelerating but so far neglected loss of species which is biased towards high-mountain specialists.
How to cite: Dullinger, S. and the GLORIA-Europe Team: High-elevation specialists increasingly disappear from European mountaintop floras, World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-375, https://doi.org/10.5194/wbf2026-375, 2026.
Biodiversity loss is one of the main global-scale challenges our planet is facing. In European marine and coastal waters, biodiversity loss is caused by multiple human activities such as overfishing (reducing fish and invertebrate stocks and harming vulnerable species) and climate change (shifting species distribution towards colder waters and enabling biological invasions of species from warmer waters). As the causes of biodiversity loss in European marine ecosystems were identified, legislation and policies to counteract the losses were implemented. For example, the Common Fisheries Policy introduces fishing quotas and Marine Protected Areas limit some of the most prejudicial human activities. In sum, there are two opposing processes acting on coastal and marine biodiversity: losses caused by human activities and gains caused by conservation efforts.
We aim to describe European marine and coastal biodiversity temporal trends to understand if biodiversity loss is worsening, stagnant or improving. We also want to determine if these trends are similar across European regions and for different groups of organisms. To do so, we estimated the temporal trends in richness, diversity and abundance for five biotic groups (i.e. fish, invertebrates, macroalgae, phytoplankton and zooplankton) across five European regions (i.e. Atlantic Ocean, Arctic Ocean, Baltic Sea, Black Sea and Mediterranean Sea).
The data was extracted from open-access databases (BioTIME, EMODnet, REPHY, FishGlob, Continuous Plankton Recorder Survey), the final dataset comprising 2,066 time series, spanning from 1956 to 2022 with a mean total duration of 18 years and a mean of 15 sampled years. For each time series and metric, we fitted a Generalized Least Squares (GLS) model and, to detect differences in the trends across geographical regions, the resulting slopes of the GLS models were meta-analysed.
Most communities showed no significant change, suggesting no further widespread biodiversity loss during the observation period. Positive trends were found for invertebrates in the Baltic, and negative ones for fish in the Atlantic. However, uneven data coverage limits this generalization, highlighting the lack of sufficient rigorous monitoring of biodiversity and of accessibility to existing data.
How to cite: Peredo Arce, A.: Biodiversity trends for five European marine biotic groups, World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-484, https://doi.org/10.5194/wbf2026-484, 2026.
The ongoing biodiversity crisis, marked by global wildlife declines and high extinction rates that undermine ecosystem function and essential ecosystem services, is also evident in European marine ecosystems, where coastal birds have experienced marked population losses due to overfishing, habitat degradation, pollution, and decades of hunting. Despite conservation efforts and the establishment of protected areas, many species remain threatened. Numerous studies have assessed long-term population trends of individual coastal bird species; however, research addressing changes at the community level across broad temporal and spatial scales remains limited. Here, we used a large-scale database of 308 time series of coastal bird communities collected between 1957 and 2024 across the Baltic Sea, the North Sea, and the Western Mediterranean Sea to assess how abundance, taxonomic and functional diversity have changed over the past decades, and to evaluate the effect of conservation areas on coastal bird communities.
Our results showed overall increases in taxonomic richness (1.7% per year on average), taxonomic diversity (1.4%), abundance (2.7%), functional richness (4.1%) and functional evenness (0.7%) of coastal bird communities. However, trends were highly variable across sites, including 4.5% of them experiencing significant declines in species richness, 5.2% in taxonomic diversity, and 13.3% in abundance. Although these overall increases were similar across the three regions studied, they were not uniform within them. For example, recovery in the Western Mediterranean Sea occurred primarily between 1970 and 2000, while in the Baltic Sea, increases have occurred since 1995. Our results also showed the relevance of conservation areas for coastal birds, especially those strictly protected (i.e., IUCN Categories of Protected Areas Ia, Ib or II). However, we also found that some non-protected sites are recovering at rates similar to—or even exceeding—those observed in strictly protected areas.
Despite overall improving trends, many coastal bird communities continue to face persistent declines due to site-specific stressors and broader pressures such as overfishing, bycatch, habitat degradation, and climate change. Ensuring long-term conservation success will require not only well-managed protected areas and strict conservation policies but also strengthened monitoring, international collaboration, and adaptive strategies across European seas.
How to cite: Cano-Barbacil, C., Bowler, D., Ballesteros-Pelegrín, G., Bertolero, A., Deneudt, K., Genovart, M., Gómez-Serrano, M. Á., Hernández-Navarro, A., Oro, D., Zamora-López, A., and Haase, P.: Signs of coastal bird community recovery over seven decades in three European seas, World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-533, https://doi.org/10.5194/wbf2026-533, 2026.
Butterfly Monitoring Germany is a programme with a central citizen science component. It is coordinated by the Helmholtz Centre for Environmental Research – UFZ and the Society for Butterfly Conservation (GfS), and numerous butterfly experts support the programme on a voluntary basis with their expertise. Since 2005, volunteers have been counting butterflies along fixed routes (= transects) using a method established throughout Europe, known as "Pollard walks".
In 2023, data was collected on a total of 620 transects. A special feature of Butterfly Monitoring Germany is that many transect walkers have been participating for many years. For example, 241 of the 620 transects evaluated in 2023 have been monitored for 10 years or more, and 73 transects have been monitored since 2005, i.e. since the start of the project.
The database has improved over time, enabling us to calculate trends for 82 butterfly species. Over the years, many (but not all) species have shown a negative trend. Frequent and widespread species in particular often show a positive trend, while negative trends can be observed especially in specialised and/or rare species.
Trends can also be calculated for species groups, such as grassland butterfly species. The Grassland Butterfly Index (GBI) has been calculated across Europe for many years based on data from the various butterfly monitoring programmes in the different countries. The GBI is based on trends in 17 butterfly species that are typical of grasslands. The latest trend shows a sharp decline in grassland butterfly species across Europe. In 2025, the GBI was calculated for Germany for the first time, using the same methodology as for the European Index. Unlike the European index, however, only data from 15 species of grassland butterflies can be included in the calculation for Germany. For two species, the data available is not sufficient to calculate a reliable trend.
We present the results of the trend calculations for butterfly species in Germany as well as the results of the German GBI.
How to cite: Kühn, E., Harpke, A., Musche, M., Schmitt, T., and Settele, J.: 20 years of Butterfly Monitoring Germany – calculating trends and indicators using citizen science data, World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-382, https://doi.org/10.5194/wbf2026-382, 2026.
With concern mounting that insect biodiversity is being harmed by human activities there is an urgent need for robust evidence to support or refute these contentions. This is particularly critical in freshwaters which are widely considered among the most threatened ecosystems on earth. In many high-income countries, river insect communities have been regularly sampled for decades for national water quality monitoring purposes. Here, such data, from Europe, the Americas, Oceania, South Africa and South Korea, have been compiled and analysed using linear mixed-effects models to quantify trends in the abundance and prevalence of insect families. Time series (>9-year span and with >9 sampling occasions) extended from 1965-2023 with the vast majority of being from Europe and most sampling effort occurring post-1985. Across all time series, there were many more insect families with increasing than decreasing abundance trends; particularly among the Plecoptera, Trichoptera and Diptera. Leuctridae, Glossosomatidae and Empididae were among the families with the most pronounced increases in abundance while those in decline included Capniidae, Uenoidae and Culicidae. There was not a consistent pattern in trends of abundance across all locations for individual insect families, with different territories potentially being subject to different pressures or at different stages along the environmental degradation/recovery trajectory. We produce a multi-family index of fitted trends using state-space models that propagate uncertainty associated with individual family trends. Recovery trajectories are evident in Europe and Oceania but not so in South Korea or North America. The extent to which intrinsic biological traits can account for variation in trends between taxa was explored. Insect families with a greater prevalence of omnivory and with a lesser prevalence of predation were more likely to be increasing in abundance. We demonstrate that re-purposing freshwater bioassessment datasets has potential to fill knowledge gaps on state and trends in the abundance of aquatic insects.
How to cite: Murphy, J. F., Jones, J. I., Park, Y.-S., Hwang, S.-J., Dyer, E., and Woodcock, B.: Freshwater insect abundance trends vary between continents and families, World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-654, https://doi.org/10.5194/wbf2026-654, 2026.
Since the industrial revolution the combustion of fossil fuels has been releasing oxides of sulphur and nitrogen into the atmosphere. These react to form strong acids which return to the earth’s surface as “acid rain”. As a result, many waters in areas with low acid neutralising capacity had become severely acidified resulting in severe degradation of affected ecosystems. Concerted international efforts have dramatically reduced the emission of acidifying gases to the atmosphere. The UK Upland Waters Monitoring Network (UWMN) established a network of stream and lake sites from sensitive geologies across the United Kingdom, which have been monitored continuously since 1988 to assess the chemical and biological response of acidified lakes and streams to these reductions in atmospheric pollution. The UK UWMN consists of an ongoing, 35+ year time series of matched environmental data that documents the trajectory of hydrochemical and biological (macroinvertebrate, diatom and macrophyte, plus fish to 2015) recovery at 23 sites, the majority of which are acidified. International legislation has led to large reductions in acid deposition, which in turn has driven major reductions in water acidity accompanied by increases in dissolved organic matter. As such, the UK UWMN provides a national-scale natural experiment to examine how these upland aquatic ecosystems are responding to reductions in this long-range, transboundary pressure. There have been major changes in the biological communities of the majority of UWMN sites, driven mainly by a turnover of taxa rather than an increase in richness. There is strong agreement between the sites showing positive trends in biological indicators of water pH and the sites that are undergoing the clearest chemical recovery from acidification. However, there are also indications that other drivers of change, such as nitrogen enrichment and climate change, may be causing recovery trajectories to deviate from paths taken during acidification as, for example, indicated from palaeoecological data. The UK UWMN has proven, and is continuing to prove, to be a highly effective source of evidence for assessing the efficacy of emissions reduction policy in restoring damaged upland freshwater ecosystems within the context of other regional pressures.
How to cite: Jones, I., Murphy, J., Shilland, E., Juggins, S., Henderson, G., Pretty, J., Cooling, D., Layer-Dobra, K., Arnold, A., and Monteith, D.: Recovery of acidified surface waters in response to reduced atmospheric pollution: 35+ years of continuous biological monitoring (1988–2025), World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-755, https://doi.org/10.5194/wbf2026-755, 2026.
Communities exhibit temporal variability that can be amplified by both natural and anthropogenic environmental changes. Such variability, the inverse of stability, influences ecosystem processes, compromising their functionality. In degraded communities, biodiversity loss might affect temporal stability and weaken ecosystem functioning, whereas in less impacted communities, higher biodiversity enhances aggregate properties (e.g., abundance and composition) and tends to stabilize ecosystem dynamics. A critical question is whether changes in the ecological status of ecosystems affect the ability of communities to buffer environmental variability and maintain ecosystem functions.
Here, we analyzed 4,530 time series of river invertebrates collected between 1971 and 2024 across 23 European countries, encompassing a gradient of ecological status trajectories from degradation to recovery. We quantified temporal trends in community variability based on abundance, taxon composition, and trait composition, and assessed how they relate to trends in ecological status. We further assessed the direct and indirect roles of population-level variability, taxon and trait synchrony (concordant fluctuations), and changes in diversity (richness trend) as mediators of the relationship between community variability and ecological status.
We found that improving communities exhibited lower temporal variability in abundance, taxon and trait composition, indicating increased stability, whereas degrading communities were less stable. For abundance, increasing diversity contributed to stabilization, whereas higher synchrony slightly increased variability, suggesting compensatory dynamics, and population-level variability had a negligible effect. For taxon composition, synchrony slightly increased variability, while for trait composition, population-level variability slightly reduced it. Improvements in ecological status were also associated with higher stability of key ecosystem functions, including dispersion (recolonization dynamics), feeding guilds (energy flows), and resistance forms (disturbance tolerance).
Our findings show that changes in ecological status are linked to the stability of community structure and ecosystem functionality. Improving communities display higher temporal stability, reinforcing the importance of ecological recovery for sustaining reliable and predictable ecosystem functions and services.
How to cite: Cortes Guzman, D., Aroviita, J., Bradley, C., Cañedo-Argüelles, M., Cosson, E., Cunillera-Montcusí, D., Escaffre, R., Feeley, H. B., Ferréol, M., Floury, M., Forio, M. A. E., Goethals, P., Huttunen, K.-L., Karaouzas, I., Larrañaga, A., Moulinec, A., Peredo Arce, A., Vannevel, R., Wilkes, M., and Haase, P.: Ecological recovery increases temporal stability in European river invertebrate communities, World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-192, https://doi.org/10.5194/wbf2026-192, 2026.
Despite covering less than 3 % of Earth’s surface, freshwater ecosystems are highly biodiverse (they host nearly 9.5 % of all described animal species) and provide crucial services like drinking water, food and recreation. However, a long history of anthropogenic exploitation has made freshwater ecosystems among the most heavily impacted during the ongoing sixth mass extinction. In this context, high-resolution time series are essential to provide evidence-based management, infer trends in taxonomic and functional diversity, and ultimately understand how biological communities respond to stressors over time. In this study, we analyse long-term data gathered by the Water Agency of the Basque Country from over 170 sampling sites corresponding to 21 river catchments in Northern Spain, including biological (e.g., macroinvertebrate and fish abundance), hydromorphological (e.g., flow and habitat quality indexes), and more than 21 abiotic variables. These variables were sampled twice a year across 30 years, thereby providing both interannual and intraannual (i.e., seasonality) information. Here we present trends in abundance, taxonomic and functional diversity in relation to the physicochemical properties of the habitat, and explore changes in seasonality over the past decades. Our results reveal a significant decline in fish abundance and diversity, and a slight increase in both the abundance and diversity of macroinvertebrates. River catchments show a trend towards environmental homogenization as they become more oxygenated and less polluted. Since river physicochemical status improved over the past three decades, the observed differences among macroinvertebrate and fish may be driven by hydromorphological alterations. Intraannual differences in abundance between samplings before and after the summer period have diminished and, is some cases, reversed, suggesting a shift in the phenology of the organisms studied. Altogether, our study highlights the potential value of exploring manager-gathered data from water quality monitoring to reveal long-term and seasonal patterns in freshwater communities essential for tackling the challenges posed by global change.
How to cite: Larretxi-Gallastegi, I., Montoya, D., and Larrañaga, A.: How streams change over time? 30 years of community changes and seasonal dynamics, World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-315, https://doi.org/10.5194/wbf2026-315, 2026.
Accurate estimates of biodiversity change are more important than ever before. However, biodiversity data often suffer from limitations that could produce unreliable trends. One common limitation is low temporal resolution, with many broad-scale biodiversity studies quantifying trends using just two or three sampling years per site. Such low-resolution data could potentially inflate trend errors, producing misleading conclusions about biodiversity change. At the same time, low resolution data are often the only data available, and conclusions drawn from these data can still be broadly accurate, suggesting certain limitations may be acceptable without introducing substantial bias. In this presentation, we discuss how different temporal data limitations affect biodiversity trend estimates. We do so using European-scale data for 1,353 river invertebrate communities sampled almost annually for 10 to 29 years across 18 countries. Using each time series, we simulated lower sampling frequencies from annual to every 2–6 years, and shorter durations from 10 total years to 9–2 years, then compared how these changes affected trend directions (i.e., positive or negative) and the estimated magnitude of change. We further supplemented these analyses with a comparison of our data with those of a lower resolution dataset from the European Environment Agency (EEA) for the same rivers. Reducing sampling frequency had a minor effect on trend direction errors, with 87–74% sites still matching in direction. Conversely, magnitude errors increased more substantially, from matches of 89% when sampling occurred every 2 years down to only 12% when sampling every 6 years. We found similar changes in error rates with reduced duration, for shorter (≥10 years) versus longer (≥20 years) time series, and for our comparison of the two monitoring datasets. Our findings show that temporal data resolution can greatly impact the estimated magnitude of biodiversity change, whereas its direction is less sensitive. Consequently, obtaining accurate estimates of both magnitude and direction requires high-resolution time series, whereas lower-resolution data may only reliably capture direction. These results highlight the value and limitations of temporal biodiversity data, with implications for future monitoring and broad-scale investigations of biodiversity change.
How to cite: Sinclair, J. S. and Cortés-Guzmán, D. and the contributors to the Synthesis Center on Freshwater Biodiversity Change in Europe: Robust estimates of biodiversity change require high-resolution time series, World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-489, https://doi.org/10.5194/wbf2026-489, 2026.
Species and ecosystems are being reshaped under intensifying human pressures. While insects have often been overlooked in biodiversity assessments, recent reports of dramatic declines have drawn increasing attention from researchers and the wider society. However, systematic evaluations of change for insect taxa remain scarce due to a lack of monitoring data. Lepidoptera (butterflies and moths), a mega-diverse group sensitive to environmental change, are an exception, as they benefit from extensive long-term monitoring and trait databases, making them an ideal model for assessing insect responses to global change drivers. On the other hand and despite many studies focusing on Lepidoptera, comprehensive analyses across regions and taxa are still lacking. We compiled a global database integrating more than 100 monitoring schemes and over 12 million abundance records from thousands of species spanning several decades and including over 40 countries. We estimated temporal trends in species richness, total abundance and evenness using hierarchical Bayesian mixed models, after spatially gridding the data and applying sample-based rarefaction across years. Despite the breadth of these data, records remain heavily biased toward temperate regions in the global North, with tropical regions underrepresented. On average, Lepidoptera communities have become more diverse and more even. Yet these trends are highly context-dependent and strongly influenced by local temperature change, with stronger effects observed in areas experiencing rapid warming. Abundance dynamics were complex, differing between butterflies and moths, and driven disproportionately by common species that shaped relative abundance patterns over time. These findings highlight the multifaceted impacts of temperature across space and time, with communities restructuring along divergent pathways. They underscore the importance of evaluating multiple dimensions of biodiversity to capture the full scope of ongoing change. While results are preliminary, this global synthesis provides a foundation for understanding insect biodiversity responses and for guiding conservation strategies in a rapidly changing world.
How to cite: Antão, L.: Beyond declines: complex and context-dependent responses of Lepidoptera communities under climate change, World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-620, https://doi.org/10.5194/wbf2026-620, 2026.
Insects in temperate regions exhibit tightly regulated life cycles, with overwintering occurring in distinct developmental stages that are physiologically adapted to low temperatures. During the vegetation period, phenological processes such as hatching, mating, and larval development are likewise strongly influenced by ambient weather conditions. The pronounced synchrony of long-term trends in insect biomass across diverse habitats suggests that weather patterns and associated anomalies constitute major drivers of population dynamics. We identified a priori life-history phases expected to be particularly sensitive to climatic variability and quantified corresponding weather conditions and anomalies for each period. Incorporating these variables, we modelled variation in insect biomass using 27 years of data. The findings reinforce previous results indicating that, in addition to cold and wet summers, particularly warm and dry winters exert pronounced negative effects on insect populations. Using only the weather variables from our model, we were able to predict insect biomass in independent validation datasets with substantial accuracy. Our results indicate that weather conditions and anomalies represent an underappreciated yet highly influential component in the ongoing discourse on insect decline. For rare species, population reductions driven by adverse weather over decadal time scales may plausibly contribute to local extirpations, especially in small and fragmented habitats where compensatory colonization–extinction dynamics, as posited by metapopulation theory, are constrained by the high spatial and temporal synchrony of weather conditions. Given that many species have not yet adapted to rapid climatic shifts, the conservation implications are considerable: maintaining and restoring extensive, high-quality habitats capable of supporting demographically viable populations appears to be the most effective buffer against increasing climatic unsuitability. Together with previous findings, our results suggest a complex interplay in which suitable weather conditions primarily influence overall population biomass, whereas land-use strongly shapes species composition and diversity. Furthermore, these findings underline that insect biomass—being driven by factors distinct from those shaping diversity—should not be used as a surrogate for insect diversity but rather as an indicator of insect population wellbeing more generally.
How to cite: Müller, J.: Complex unsuitable weather conditions as a key stressor for insect populations in the temperate zone, World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-408, https://doi.org/10.5194/wbf2026-408, 2026.
Species are shifting their geographical ranges in response to climate change by going locally extinct at sites that become unsuitable and by colonizing newly suitable sites. However, the velocity of these local extinctions and colonizations seem to lag behind recent environmental change for the majority of mountain plant species, entailing so-called extinction debts and colonization credits that will have to be paid off in the future. This implies that further species re-distributions are to be expected based on environmental changes that occurred in the past, even if climate change was halted now. Due to the very limited availability of historical long-term datasets, such range shifts and range lags are so far only reported as temporal snapshots that compare current species distributions to one particular time in the past. The temporal development of species’ local extinctions and colonizations as well as of their extinction debts and colonization credits thus remain elusive. Yet, climate change has accelerated over the recent decades and it seems more and more likely that this trend will continue in the future. The relaxation times of extinction debts and colonization credits in response to climate change (i.e. the time required for the distribution of a species to reach equilibrium with occurred environmental conditions) are thus becoming increasingly important to reliably predict the future trajectory of mountain biodiversity. To address this, we calculated species distribution models with an annual resolution over the last six decades based on >40’000 vegetation plots from all European mountain ranges recorded by a multitude of scientists. We found that even though the number of local extinctions and colonizations increased generally over time, mountain plant species increasingly accumulated extinction debts and colonization credits. Their distributions are thus more and more out of sync with the environment and are increasingly veiling past effects of climate change on mountain biodiversity yet to come, reinforcing warnings about potential climate-driven ecological disruptions in the future.
How to cite: Johnson, C., Zurell, D., and Rumpf, S.: Temporal trends of climate-driven lags of mountain plant distributions, World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-180, https://doi.org/10.5194/wbf2026-180, 2026.
In many regions on Earth, past and current changes in temperature, rainfall patterns, and snow cover are concomitant with changes in atmospheric pollution, probably causing interactive but overlooked impacts on ecosystems. However, in global-change ecology, we often study the interactive effects of climate changes (mainly temperature warming) and chemical pollution experimentally at short spatio-temporal scales and in controlled conditions. As a result, how these global change factors interact to shape long-term population dynamics in natural ecosystems, remains little known. As a key example, the European Black Triangle — the region at the borders of former Czechoslovakia, Germany, and Poland — was heavily air polluted in the 1970s and 1980s due to emissions from coal power plants, resulting in high loads of toxic element deposition (e.g., lead). In the Ore Mountains, within the Black Triangle region, we collected during 40 years (twice a year in June and October) the abundances of six small-mammal species belonging to three trophic guilds (omnivores, insectivores, and herbivores). We complemented this dataset with atmospheric pollution (SO₂, NOx, and total Particulate Matter), temperature, snow cover, and runoff (snowmelt and rainfall) historical data. Firstly, we studied the local stability (Lyapunov local stability) of the global change factors and small-mammal multivariate time series, respectively, and identified that periods of instability in climate and atmospheric pollution were preceding periods of small-mammal assemblage instability. Secondly, we used Bayesian Multivariate (Dynamic) Generalized Additive Models (MDGAMs) to test contrasting hypotheses on how different climate factors (snow cover, runoff, and temperature) may interact with temporal changes in pollution in a trophic-guild-specific manner. We showed evidence for guild-specific effects of climatic variables and atmospheric pollution. For instance, the strength of the negative interaction between runoff and atmospheric pollution on population dynamics depended on the trophic guild, with stronger negative effects on omnivores. We finish by discussing the implications of our findings on how global change factors contribute to community dynamics, and what this entails for species coexistence and biodiversity conservation amid ongoing changes in climate and atmospheric chemical composition.
How to cite: Zárybnická, M., Bejček, V., Št'astný, K., Sedláček, F., Zima, J., Rakovec, O., and Rota, T.: Looking back to the future: Four decades of global-change forcing on small-mammal assemblage dynamics, World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-842, https://doi.org/10.5194/wbf2026-842, 2026.
Freshwater biodiversity is declining faster than in any other ecosystems, yet the drivers of change in large rivers remain poorly understood. Disentangling these drivers is particularly challenging, as stressors frequently interact, and long-term, high-resolution datasets needed to detect and capture their effects are scarce. Using an exceptional 42-year dataset of fish and macroinvertebrate communities from two large rivers in France (the Rhône and Loire rivers), we addressed the relative influence of climate change (water temperature and river flow), changes in water quality and biological invasions on food web structure and function.
We found a gradual restructuring of community composition and taxa abundances from the early 1980s, with a drastic acceleration of changes in macroinvertebrate communities during the past two decades. Among explanatory variables, increasing water temperature and the expansion of non-native species emerged as the dominant drivers of change in both fish and macroinvertebrate assemblages.
To further explore ecosystem-level consequences of these community turnovers, we inferred the structure of food-webs and the fluxes of energy between taxa, and investigated how they changed across time. Our results reveal substantial shifts in food-web structure, including an increased number of species with more connections between them, as well as an unexpected lengthening of food chains. We found that the arrival and spread of non-native species accounted for much of the food-web structural reorganization over time. The proportion of energy fluxes controlled by non-native species rose sharply in recent decades, highlighting their growing influence within these ecosystems. Increased predation and competition from non-native species have likely exacerbated declines in native populations. In parallel, rising water temperatures associated with climate change also altered energy fluxes within the trophic network, notably by increasing metabolic demand and thus energy flux controlled by top predators.
By clarifying mechanisms underlying biodiversity changes in different large-river ecosystems, our study represents an important step toward disentangling multiple stressors impacts, an essential requirement for effective ecosystem management and conservation. Moreover, our findings underscore the need to consider entire communities, including non-native species, and to adopt food-web perspectives to better understand and anticipate the ecological consequences of global change.
How to cite: Vallin, J., Maire, A., Floury, M., Daufresne, M., and Sentis, A.: Unravelling 42 years of biodiversity and trophic changes in large-river ecosystems under multiple stressors, World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-764, https://doi.org/10.5194/wbf2026-764, 2026.
Long-term datasets are essential tools for tracking and understanding temporal changes in biodiversity at community level.
Freshwater zooplankton organisms are a key component of lake food webs and sensitive indicators of changes in ecosystem structure and functioning. A major challenge under climate change is to disentangle the effects of lake warming from changes in lake trophic conditions, and ultimately to relate them to variations in zooplankton communities and overall, to ecosystem functioning. Lake Maggiore (Italy) represents an ideal environment for discerning trophic from climatic impacts, as two distinct phases can be identified: an oligotrophication phase from the 1980s to the 1990s and a more recent phase characterized by water warming with a prolonged thermal stratification.
We analyzed long-term data (1981–2019) of zooplankton biomass from Lake Maggiore, a LTER-Italy site (Italian Long-Term Ecosystem Research network), collected through the monitoring program funded by the Commissione Internazionale per la Protezione delle Acque Italo-Svizzere (CIPAIS). Data were collected monthly at the deepest part of the lake, representative of the pelagic zone. Our aim was to evaluate the application of biomass-based zooplankton indices to improve our understanding of temporal changes in the lake ecosystem.
Data analyses across different taxonomic groups, at both annual and seasonal scales, revealed a declining summer contribution of Daphnia sp. in recent years and an increase in microzooplankton (nauplii and monogonont rotifers), exhibiting rapid growth and declining phases and possibly failing to control surges in phytoplankton.
This study highlights the importance of long-term monitoring, seasonality analysis and the inclusion of the entire zooplankton size spectrum as key components for interpreting lake ecosystem functioning in response to lake trophic and climatic changes. Moreover, our findings suggested that the developments of zooplankton indicators should consider seasonal rather than annual values and that zooplankton biomass represents the most informative parameter, incorporating both abundance and size structure of the zooplankton community.
How to cite: Piscia, R., Caroni, R., and Manca, M.: Indicators of Climate-Driven Change in Long-Term Zooplankton Composition: Insights from Lake Maggiore (Italy), World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-536, https://doi.org/10.5194/wbf2026-536, 2026.
The European Alps are among the richest biodiversity hotspots of global importance. Yet, their unique and fragile ecosystems make this area particularly vulnerable to intensified land use and climate change, requiring urgent action to identify priority areas for restoration and conservation.
Long-term biodiversity data are essential tools for developing representative ecological indicators and indices that can detect environmental change driven by anthropogenic activities, including shifts caused by climate change. Furthermore, existing indicators and indices typically focus on lowland ecosystems, or specific habitat types, leaving significant gaps in alpine contexts (e.g., the Farmland Bird Index and the European Grassland Butterfly Index). Additionally, biodiversity data across the European Alps remain highly fragmented due to variations in sampling protocols, or due to geographical patterns in species and expertise distribution.
We propose an expert-based approach that follows the Essential Biodiversity Variables (EBVs) framework, integrated by a data-based approach linked to available taxon-specific long-term monitoring datasets across the European Alps. Our aim is to develop a comprehensive baseline biodiversity dataset that facilitates the identification of representative indicators, and the development of indices for the entire European Alpine region. Using responses from targeted questionnaires focused on different taxa, we will map where different monitoring methods and programs exist for each taxonomic group, to reveal geographical gaps where additional biodiversity monitoring is needed. Moreover, the questionnaires' results will reveal quantitative and qualitative methodological information about long-term monitoring schemes in force across the Alps.
Preliminary findings from the questionnaires revealed that butterflies are the most monitored pollinators group in the European Alps. In addition, only a few, long-term monitoring projects run on pollinating insects and birds include sampling locations above the 2,500 m asl, highlighting an urgent need for increased monitoring effort at higher elevation, especially targeting the alpine environment. These insights can help integrate existing guidelines aimed at effectively monitoring taxonomic groups or species (see the recently updated guidance for aligning public and private practices with the EU Pollinator Monitoring Scheme - EUPOMS) or provide a foundational resource for stakeholders interested in initiating long-term monitoring of other taxa (i.e., mammals and birds), making any newly-developed biodiversity monitoring efforts more compatible with ongoing initiatives across the European Alps.
How to cite: Corsini, M., Guariento, E., Anderle, M., La Morgia, V., Tappeiner, U., and Paniccia, C.: Towards the development of taxon-specific indices for the European Alps , World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-830, https://doi.org/10.5194/wbf2026-830, 2026.
The sustainability of biodiversity and ecosystem services – critical to human well-being in the coming century – is severely threatened by global change drivers. By understanding the shape and speed of biodiversity and ecosystem service responses to these drivers, we can manage trade-offs between them and identify future hotspots. Here, we focus on land use change, as perhaps the most pervasive driver of biodiversity and ecosystem service loss, with wide-ranging impacts, both immediate and over time.
We use space-for-time substitution to model the relationship of urban and agricultural land use to 30 indicators of biodiversity and ecosystem services across global biomes. Our results indicate differing trajectories – in general provisioning services and the usage of other services show clear increasing trends with land use. However, biodiversity indicators and regulating service supply show declines or thresholds as land use increases. The strongest relationships are found in tropical and temperate biomes. We then explore if incorporating historical land use change into our models can better predict current biodiversity and ecosystem services due to the potential time lags in impacts. This resulted in an improvement in the majority of models (85%), but these improvements were generally small.
Finally, we apply land use projections from the Shared Socioeconomic Pathway scenarios to our more robust models to predict future changes in biodiversity and ecosystem services. The biggest differences were found between SSP1 (sustainability) and SSP3 (regional rivalry), most prominently in central and southern Africa and southeast Asia. Inflection points were present beyond 2050, meaning several indicators switched from gains to loses, particularly with the SSP5 (fossil fuelled) scenario. Taken together, our findings show the potential for developing robust biodiversity and ecosystem service trajectories at the biome extent; that incorporating historical land use change can improve these trajectories; and that such trajectories can highlight areas of potential future losses.
How to cite: Reader, M. O. and Santos, M. J.: Global responses in biodiversity and ecosystem services to future land use change, World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-880, https://doi.org/10.5194/wbf2026-880, 2026.
Long-term changes in freshwater and coastal ecosystems is tightly linked to anthropogenic drivers, yet understanding these trajectories requires coherent, high-resolution time series that span entire land-river-sea continuum gradients. Using the source-to-sea paradigm and a conceptual model linking upstream protected areas to downstream coastal conditions (ecosystem services, mediating flows and ecological responses) we evaluated how upstream terrestrial and freshwater conservation areas influence ecosystems across four major European land–river–sea systems: the Danube River - Black Sea, Po River - Adriatic Sea, Elbe River - North Sea and Guadalquivir River - Atlantic Ocean. Drawing on available multi-decadal datasets on protected areas, nutrient (nitrogen and phosphorus) concentrations, ecological water quality based on Water Framework Directive reported ecological quality ratios (EQRs) and chlorophyll-a we developed an integrated conceptual and empirical framework spanning 1990–2024. We analyse how basin wide protected areas extent shape nutrient attenuation and ecosystem functioning across freshwater, transitional, and coastal domains. Strong multi-decadal declines in nitrogen—and to a lesser extent phosphorus—emerge in the Danube and Elbe rivers, particularly in freshwater and transitional waters, where increased protected-area basins coverage aligns with reduced nutrient concentrations and lower chlorophyll-a, signalling improved ecosystem functioning and reduced eutrophication risk. These effects propagate, albeit attenuated, into coastal zones, demonstrating that upstream conservation can generate measurable downstream benefits. In contrast, the Po and Guadalquivir systems exhibit weak or undetectable trends, reflecting extensive hydromorphological alteration, fragmented wetlands, or severe monitoring gaps that obscure underlying functional changes. Across basins, results highlight the critical role of floodplain connectivity, land-use intensity, and legacy pollution in shaping long-term nutrient trajectories, as well as the limits imposed by non-harmonised, discontinuous monitoring—especially in transitional waters. The analysis underscores the urgent need for integrated basin-to-coast observation systems, such as those being advanced by eLTER, to co-locate biodiversity, ecosystem-function, and driver data. By linking nutrient and chlorophyll dynamics to ecosystem service pathways, the study provides a functional lens to interpret biodiversity change in the Anthropocene and demonstrates how data limitations currently bias our capacity to detect trends and attribute them to conservation actions.
How to cite: Adamescu, M., Arhire, G., Bergami, C., Keuter, S., Hufnagel, L., Madon, B., Peredo, A., Igescu, D., Haase, P., and Pade, N.: Detecting long-term trajectories in ecosystem functioning across European land river sea continuum: insights from four major river basins - Danube, Po, Elbe and Guadalquivir, World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-778, https://doi.org/10.5194/wbf2026-778, 2026.
Aquatic environmental quality plays an essential role in the growth, survival, and abundance of flora and fauna species in the ecosystems. Change in the physiochemical properties and biological quality of the ecosystem has a deleterious effect on the organisms in their habitat. Due to increasing levels of anthropogenic activities that range from agriculture, mining, fishing, and aquaculture, toxicity burdens have been imposed on the environment, forcing organisms to migrate or face extinction. Waste generated from agriculture through organic and inorganic means and pesticides washed from farmland periphery to the boundaries of reservoirs into the aquatic habitat have compromised the quality of water acceptable for organisms’ survival. Adding to the load of waste draining from outside the water is the direct deposition of organic feed waste, excreta of the cultured fish, and washed mine waste, which exacerbate the water quality by increasing the nutrients and heavy metals level, causing eutrophication and lethal toxicity of the water. These have affected the biodiversity of the freshwater ecosystem in Ghana, leading to declining numbers of macroinvertebrates. Recently, pesticide levels in water have been found to be low, such as organophosphate/synthetic pyrethroid and organochlorines, which were <0.01 µg/L and <0.005 µg/L, respectively. While in the sediment, there were high levels of zinc, with 7.5 ± 0.86 mg/L, and lead, with 0.4 ± 0.03 mg/L, reported. As a result, a narrative review was conducted on peer-reviewed studies and systematically analyzed using databases like Google Scholar, Web of Science, PubMed, and EBSCO. The results revealed an increasing concentration of ammonia, nitrates, nitrites, organophosphates, and organochlorines. Again, the result found that biodiversity, such as fisheries and other macroinvertebrates, was declining in the reservoirs. The study observes a lack of coordinated policies and commitment to regulate the use of these contaminants near the reservoirs. Hence, the study recommends proper management practices, regulation, and enforcement of laws on how these contaminants should be utilized. Designing policies and educating farmers on the need for collaborative management of the reservoir would help maintain its productivity and contribute to sustainability in practice around the reservoirs.
How to cite: Iddrisu, F. T., Baidoo, K., Samuel Opoku, D., Abarike, E. D., Akongyuure, D. N., Abobi, S. M., Ampofo-Yeboah, A., and Alhassan, E. H.: Environmental impact of organic and inorganic contaminants on aquatic species population structure and water quality in the reservoirs , World Biodiversity Forum 2026, Davos, Switzerland, 14–19 Jun 2026, WBF2026-815, https://doi.org/10.5194/wbf2026-815, 2026.
