Orals: Mon, 28 Apr | Room -2.33
Beavers are ecosystem engineers and were once widespread across Europe and North America. They are now being reintroduced to much of their native range. A growing body of evidence has shown the return of the beaver can provide multiple benefits, including for biodiversity, natural flood management and drought resilience (Brazier et al., 2021, Puttock et al., 2021). However, the return of beavers to intensely managed and highly populated anthropogenic landscapes can also bring management challenges. Pragmatic evidence based policies are required to maximise the benefits and minimise the conflicts associated with the return of the beaver.
Results will be presented from the Making Space for Water Programme which aims to support land managers to create a network of nature rich wetlands across South West England, increasing resilience to hydrological extremes. This project led by Devon Wildlife Trust, in partnership with the University of Exeter and local landowners works with wild beavers to deliver natural solutions to address societal challenges. Case studies will be presented discussing how we have combined geospatial analysis, on the ground expertise and stakeholder engagement to prioritise sites where the Nature-based Solution benefits of beavers may be greatest and direct opportunities exist for least risk.
References
How to cite: Puttock, A., Barclay, H., Holden, M., Burgess, P., and Brazier, R.: Making Space for Water: Nature-based Solutions with Beavers, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-2912, https://doi.org/10.5194/egusphere-egu25-2912, 2025.
Karst landscapes, characterized by their distinctive geomorphology and biodiversity, also host rich cultural heritage represented by traditional villages. These villages reflect the complex interplay between human activity and the environment, shaped over centuries by geological, ecological, and cultural factors. However, karst regions face critical challenges such as ecological degradation, rocky desertification, and cultural homogenization, which threaten both biological and cultural diversity.This study conducts a multidimensional analysis of traditional village distribution across China’s karst landscapes and selects the Miaoling mountainous region as a representative area to explore integrated conservation strategies. Adopting a bio-cultural diversity framework, the research emphasizes the dynamic interactions between biodiversity and cultural heritage.A comprehensive evaluation of bio-cultural diversity was performed using an indicator-based approach. Biodiversity was assessed through factors such as karst lithologic development, habitats of endangered species (Andrias davidianus, Rhinopithecus brelichi, Abies fanjingshanensis, and Taiwania flousiana), and ecosystem services, including carbon storage, soil conservation, and habitat quality. Cultural diversity was analyzed based on the distribution of traditional villages, agricultural and intangible cultural heritage, historical relics, and ethnic minority communities. Priority conservation zones were spatially identified using the Zonation model.Results highlight that the central and western Miaoling regions, especially the Beipan River basin, demonstrate high biodiversity due to well-preserved karst habitats and the presence of critical species. Culturally, traditional villages—predominantly inhabited by Miao, Dong, and Bouyei ethnic groups—are clustered in areas with elevations of 600–800 meters and slopes less than 5°, such as Moon Mountain, Leigong Mountain, and along the Beipan and Douliu Rivers, reflecting their close relationship with the karst environment.Despite these overlaps, nearly half of the region exhibits limited coordination between biological and cultural diversity, with an average coupling coordination degree of 0.611. Higher coordination zones are concentrated in central Miaoling, while the eastern and western regions remain fragmented. Priority conservation zones, covering 2,286.76 km², are primarily located in small watersheds and agroforestry systems, revealing a fragmented spatial distribution.To address these challenges, a “source-corridor-network” conservation strategy was proposed, consisting of 29 primary corridors, 76 secondary corridors, and 25 key nodes to enhance connectivity and resilience. Additionally, a multi-stakeholder adaptive management framework was introduced, emphasizing policy support, community participation, and the integration of conservation with sustainable development.This study underscores the critical value of integrating bio-cultural diversity in conservation planning for karst regions. By bridging geosciences, ecology, and cultural studies, it provides strategic insights for global biodiversity and restoration initiatives, contributing to holistic and sustainable conservation practices in the face of climate change and anthropogenic pressures.
How to cite: Li, X., Yang, Q., and Tarolli, P.: Integrating Bio-Cultural Diversity for Sustainable Conservation in Karst Landscapes: Insights from the Miaoling Mountainous Region, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-4862, https://doi.org/10.5194/egusphere-egu25-4862, 2025.
Lateral connectivity, as a cornerstone of floodplain ecosystems, shapes hydrogeomorphological features, supports floodplain functions, and initiates new habitat formation processes such as fine sediment and deadwood dynamics. However, anthropogenic activities have increasingly disrupted connectivity in large-river floodplains, leading to terrestrialization processes and significant declines in freshwater biodiversity. Restoration efforts in the Upper Danube River aim to enhance hydrological connectivity within the river-floodplain system to mitigate habitat isolation and terrestrialization. Evaluating the outcomes of these efforts requires understanding the interplay between connectivity, environmental factors, and freshwater biodiversity responses.
Using the available information from a river-floodplain stretch in the Donau-Auen National Park, we compared the responses of oligochaetes and chironomids to side-channel reconnection measures across control and impacted sites before (reference period), in the short term and the long term after restoration. We applied a Before-After x Control-Impact (BACI) design to analyse the direct effect of restoration-induced habitat changes on the taxonomic and functional composition and diversity of these indicator groups. A graph theoretical approach followed by applying Partial Least Squares Regressions was used to determine the overall effect of connectivity change on the functional diversity of the indicator groups.
The BACI analysis revealed the positive effects of restoration on oligochaete taxonomic and functional diversity. However, we observed that terrestrialization processes dominate over the long term, outweighing the impacts of restoration. Variations in species traits such as longitudinal zonation, body size, dispersal strategy, drift propensity, and adult lifespan showed short-term restoration effects for both groups, returning to pre-restoration conditions in the long term. For oligochaete functional diversity, connectivity was influential shortly after restoration, while environmental factors became more significant over time.
Our findings underscore the importance of incorporating functional trait responses into restoration assessments to inform the management of protected areas. We highlight the need for restoration measures to refine strategies that enhance floodplain connectivity in the long term to ensure lasting effects on aquatic biota and recommend continuous monitoring to understand better the role of connectivity in influencing ecological processes and their cascading effects on freshwater communities.
This research acknowledged support from the EU Projects i-CONN’ H 2020 research and innovation programme under the Marie Skłodowska-Curie (grant agreement number 859937), DANSER (grant agreement No 101157942), H2020 MERLIN (grant agreement No 101036337), HEU DANUBE4ALL project (grant agreement no. 101093985), and AquaINFRA (grant No 101094434). Furthermore, the Austrian Federal Ministry for Digital and Economic Affairs and the Christian
How to cite: Recinos Brizuela, S. S., Funk, A., Graf, W., Basooma, A., and Hein, T.: Functional responses of oligochaetes and chironomids to restoration-induced changes in connectivity- A case study in the Donau-Auen National Park , EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-10337, https://doi.org/10.5194/egusphere-egu25-10337, 2025.
Micronekton is a diverse group assemblage of marine animals, described as active swimmers ranging from 2 to 20 cm. Micronekton organisms perform diel vertical migrations, feeding on nutrient-rich surface waters during the night and migrate several hundred meters at sunrise to deep waters, where they digest their food, generating an active transport of carbon. These organisms play a significant but often overlooked role in carbon sequestration within the ocean. Current models generally do not take into account the contribution of the entire community of micronekton to the carbon budget or include a large number of parameters that are difficult to test. Using a one-dimensional trait-based model with a limited number of parameters, we simulated the diel vertical migrations of micronekton and their carbon production through respiration, fecal pellets, excretion, and dead bodies. The model relies on three state variables which are the biomass of the preys, i.e. mesozooplankton, the biomass of the consumers and their gut content. During the night, micronekton reside near the surface to feed. At dawn and dusk, they swim to stay at depth during the day to escape predation from their visual predators. In the model, migrations are triggered by the gradient of light. Our model allowed us to explore the biotic and abiotic variables influencing the active transport of carbon in the mesopelagic zone, where organisms experience low light levels. The functional approach highlighted the importance of size and taxonomy, in particularly considering fish, crustacean, and cephalopod as key factors controlling the efficiency of carbon transport. Several metabolic parameters accounted for most of the variability in carbon production (organic and inorganic) and transport efficiency, mostly linked to respiration rates. Our results suggest that in temperate regions, migrant organisms are responsible for an important vertical transport of carbon. This active export showed strong seasonal variations with a maximum reached in summer. However, in the context of global warming, the evolution of the impact of micronekton on carbon sequestration remains uncertain. This underscores the imperative for future research to deepen our understanding of micronekton metabolism and vertical dynamics through a functional approach and in relation to their environment.
How to cite: Thibault, H., Ménard, F., Abitbol-Spangaro, J., Poggiale, J.-C., and Martini, S.: Modeling micronekton diel vertical migration contribution to carbon export in the mesopelagic zone, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-101, https://doi.org/10.5194/egusphere-egu25-101, 2025.
Rewilding has emerged as a prominent ecological restoration approach in recent decades. It is aimed at restoring natural processes, improving ecosystem functioning, and enhancing biodiversity with minimal human interference necessitated. Different approaches to rewilding exist, including trophic and passive rewilding. Trophic rewilding involves the active introduction of species, most often large herbivores. The latter approach involves passive management with minimal human interference. Being a nascent strategy available to ecosystem managers, comparative empirical research in the context of rewilding is lacking, especially relating to soil functions like carbon (C) and nitrogen (N) cycling and storage.
In this study, we investigated whether the choice of trophic versus passive rewilding had an impact on the quantity and cycling of C and N stored in soils. Additionally, we compared these two approaches to annual mowing and removal of biomass, a typical conservation management strategy for grasslands.
Permanently fenced passive rewilding and conservation mowing plots were established within a trophic rewilding project at Mols Bjerge, Denmark in spring 2017. Plots delineated adjacent to these represented trophic rewilding. Exmoor ponies and Galloway cattle were introduced the previous year and continue to freely roam the 120 ha site with minimal human intervention. The area has previously been used for sheep and cattle grazing research, primarily on aboveground biodiversity. In August 2024, we collected soil samples from three layers (0-5 cm, 5-10 cm, and 10-20 cm; n = 216) in each treatment replicated at 8 locations within the study site. Additional topsoil (0-5 cm; n=72) samples were retrieved from each plot for analyses of microbial activity.
Bulk density, organic carbon (OC), total nitrogen (TN), and pH were determined in samples from all depths. Microbial biomass C and N, respiration, microbial activity and diversity, and net N mineralization rates were analysed in the topsoil samples. Based on preliminary results, trophic rewilding was characterised by the largest stocks of C and N to 20 cm with mean values of 3.62 kg m-2 and 0.27 kg m-2, respectively. Passive rewilding and conservation mowing resulted in mean C stock values 11% and 19% lower compared to trophic rewilding, with similar results for N stocks. In contrast, soil C/N ratios were significantly higher under conservation mowing compared to the rewilding treatments. The lowest levels of microbial biomass C, specific (normalised for OC content) C mineralization, and net N mineralization were associated with trophic rewilding, suggesting that nutrient turnover rates are comparatively suppressed. EcoPlate™ results similarly showed reduced microbial activity, as well as diversity, under trophic rewilding with significantly higher results under mowing. These results demonstrate that the decision to include or exclude animals in land management strategies can have a consequential impact on C and N storage and the driving processes related to their cycling in soil. Therefore, this decision should be considered carefully in land management policy development.
How to cite: O'Keeffe, J., Ovesen, A., Philipsen, F. N., Christiansen, J. R., Larsen, K. S., Rojas, S. K., Rosas, Y. M., Munck, T., Kristensen, J. A., Le Roux, L., Cheng, Y., Mueller, C. W., and Vesterdal, L.: To graze or not to graze: comparing soil carbon and nitrogen storage and cycling under trophic rewilding, passive rewilding and conservation mowing , EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-11846, https://doi.org/10.5194/egusphere-egu25-11846, 2025.
Herbivory can have a major impact on the stocks and fluxes of elements in an ecosystem. As herbivores forage for limiting nutrients, the preferential consumption of certain plants over others shifts plant community composition. The well-defended plants that can resist herbivory have specialized traits often leading to lower quality litter that is slow to decompose. The dominance of well-defended species promotes a greater quantity of low-quality litter to enter the soil which then can slow the mineralization of limiting elements. When soil fertility is low, increased dominance of well-defended plant species can slow nutrient cycling leading to an herbivory-induced deceleration of ecosystem biogeochemistry. Here we present results from a 23-year fencing experiment in the south-western mountains of Norway that compares the effect of high density grazing with the effect of excluding domestic sheep. We complement the experiment with a series of natural and human-created islands in two hydroelectric reservoirs that have excluded sheep-grazing for at least sixty years and therefore can serve as a natural control. The low-alpine site (~850–1050 m) is characterized by a wet oceanic climate with a nutrient-poor granitic parent material creating a mixture of sandy soils of histosols, gleysols and podzols often with moist, deep, and acidic O-horizons.
We discovered that herbivory impacted both the plant community and ecosystem biogeochemistry in the stocks, concentrations, and ratios of silicon (Si) and phosphorus (P) in plants and soils. Our results demonstrate that sheep herbivory was associated with the dominance of herbivory-resistant grass Nardus stricta while the ungrazed islands harbored herbivory-susceptible grasses and forbs such as Deschampsia flexuosa and Solidago rigida. N. stricta was found to have low quality plant leaves with a high Si to P ratio (Si:P). Its dominance scales this high Si:P stoichiometry to the bulk aboveground plant biomass leading to a higher stock of Si under mainland herbivory compared to the island control. In comparison, the island vegetation was found to be relatively enriched in P. There were no treatment differences in the Si:P ratio between the mainland fencing treatment. N. stricta remained dominant inside many fences, suggestive of negative feedback towards the high-grazing state; however, one site transitioned to low Si:P ratio plant biomass with high D. flexuosa abundance and was classified with the islands. The present case suggests a mechanism of plant-soil-herbivory interactions where herbivory, through increasing dominance of a well-defended plant species, impacts ecosystem biogeochemistry via Si and P. Our empirical results inform theory on the role of herbivores in generating stabilizing negative feedback among ecosystem states that can aid to scale and implicate zoogeochemistry into Earth system models. We will discuss our results in the context of theory that describes herbivory-induced deceleration of ecosystem nutrient cycling. A deep understanding of herbivory-induced plant-soil feedbacks, expanded to include the stoichiometry of elements beyond carbon and nitrogen, is essential for efforts to model animals in the Earth system.
How to cite: Furey, G., Austrheim, G., Tau Strand, L., Mulder, J., Speed, J., and Martinsen, V.: Herbivory-induced alteration of ecosystem biogeochemistry: the case of domestic sheep herbivory in the Norwegian mountains , EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-12447, https://doi.org/10.5194/egusphere-egu25-12447, 2025.
How to cite: Jiao, Y. and Zhang, Z.: The Impact of Yak Dung Deposition on Litter Decomposition and Multi-Nutrient Cycling in Grassland Ecosystems, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-13489, https://doi.org/10.5194/egusphere-egu25-13489, 2025.
Large herbivores acting as ‘ecosystem engineers’ (e.g. pigs, deer, cattle, bison, ponies) have diverse effects on geophysical and ecological systems and are increasingly being incorporated in landscape restoration and rewilding projects through species (re)introductions. Through their physical behaviours such as trampling, grazing, wallowing and rootling, large herbivores can alter soil properties, vegetation structure and hydrological processes, contributing to landscape-scale changes. Despite their growing inclusion in rewilding projects, particularly in temperate regions, the geomorphic impacts of large herbivores remain poorly understood.
This systematic review and meta-analysis aims to synthesise the evidence base on the geomorphic impacts of large herbivores in rewilding and other environmental settings and identify the nature and magnitude of their impacts. Using systematic searches of Scopus and Web of Knowledge, 13,733 studies were initially identified and screened down to 461 studies for full-text review. Studies meeting key inclusion criteria (terrestrial environments, temperate biomes, relevant to rewilding settings) were retained for synthesis and meta-analysis of effect sizes. The presentation will explore the evidence base in terms of geographic distribution of studies across species, ecosystems and countries and identify key gaps. Through meta-analysis of effect sizes, it will explore the directionality and magnitude of large herbivore effects on key geomorphic processes across a range of environments relevant to rewilding. These findings provide new insights into the role of animals in shaping ecosystems.
How to cite: Moore, G., Harvey, G., Newbold, T., and Henshaw, A.: Large herbivores as geomorphic agents: insights from a systematic review and meta-analysis , EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-17028, https://doi.org/10.5194/egusphere-egu25-17028, 2025.
The Vesturdjúp Basin is located at the northeastern edge of the Irminger Sea, bordered by southern Greenland to the west, the Denmark Strait and Iceland to the north, and the Reykjanes Ridge to the east. To the south, it opens into the North Atlantic Ocean. The basin’s bathymetry is characterized by large sediment rafts shaped by intense bottom-water currents, a distinctive ocean floor fabric, and numerous cone-shaped volcanoes1. In the summer of 2024, Meteor Expedition M201 explored the seamounts of the Vesturdjúp Basin1. In addition to a comprehensive geological sampling and geophysical program, all studied volcanoes were surveyed using a towed camera system (OFOS – Ocean Floor Observation System). A total of 21 dives were conducted, covering 24.3 km of seafloor and resulting in over 65,000 still images and 38 hours of video footage. Observations revealed that lithified sediments and some manganese crusts extensively cover the seamounts of the Vesturdjúp Basin, with occasional rocky outcrops accompanied by abundant talus material and drop stones. No evidence of recent lava was detected. However, the seamounts host diverse and vibrant ecosystems that vary with depth and, more notably, with current exposure. While some seamounts show sparse macrofaunal presence, many are rich in species, such as sea pens, corals, diverse sponges, crinoids, crustaceans, octopods, and fish. This study presents the faunal diversity of the Vesturdjúp Basin seamounts, highlighting how species distribution and abundance appear to be more influenced by current dynamics and sedimentation patterns - particularly south of the Denmark Strait in the northern Irminger Sea - than by the geological features of the volcanoes.
1Augustin, N., Palgan, D., Hübscher, C.P., van der Zwan, F.M., et al., (2024) Volcanism in the Vesturdjúp Basin - Flank Igneous System or Intraplate Volcanism Off-Shore Western Iceland, Cruise No. M201, 09. June - 18. July 2024, Reykjavik (Iceland) - Praia da Vitoria (Azores, Portugal), METEOR-Berichte, M201, 1-91, https://doi.org/10.48433/cr_m201
How to cite: Augustin, N., Eisermann, J. O., Budke, L., Odinsson, D. T., van der Zwan, F. M., Garcia Paredes, E. R., Strizek, V., Prejc, M., Hübscher, C., and Palgan, D.: Macrofaunal diversity in high-bottom current environments at the Vesturdjúp Seamounts (Northern Irminger Sea, Iceland), EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-14859, https://doi.org/10.5194/egusphere-egu25-14859, 2025.
In light of European and international mandates to protect natural areas for biodiversity conservation, unused or abandoned areas are increasingly recognized as valuable resources. This study investigates the botanical and structural diversity of mining areas and surrounding landscapes across four major gypsum mining regions in Germany. Over the course of a year, we analysed 66 study transects across 24 mining sites, categorizing them based on their structure and usage. Our results indicate that vascular plant diversity in restored post-mining landscapes is significantly higher than in the surrounding undisturbed areas. This research underscores the importance of these disturbed landscapes for Red List species and the potential of recovering gypsum-mining sites in Germany to protect biodiversity. Furthermore, our findings highlight the critical role of management strategies, with particular emphasis on renaturation and recultivation as effective techniques to enhance the nature conservation value of abandoned sites.
The study also reveals the significant influence of management interventions on the ecological development of these landscapes. Renaturation, involving the restoration of natural habitats, was found to be more beneficial for biodiversity than recultivation, which often involves returning areas to agricultural or forestry use. We advocate for long-term management plans in renaturation areas, as these are essential for sustaining species diversity, particularly for areas undergoing ecological succession. Regular mechanical disturbance, applied in a mosaic pattern every 3–5 years using methods such as grazing, brush cutting, or heavy tillage, can further improve biodiversity outcomes. Additionally, after mining activities cease, the creation of a diverse range of landscape structures—such as steep walls, shallow water areas, rubble piles, and stone slabs—can support a variety of species.
This study contributes to our understanding of the potential for post-mining landscapes to serve as important habitats for biodiversity conservation. It also provides practical recommendations for nature conservation organizations, municipalities, and the mining industry. By fostering partnerships and implementing long-term renaturation concepts, we can improve the ecological restoration of mining areas and ensure their role in biodiversity protection.
Keywords: gypsum mining, biodiversity, time-for-space concept, disturbance ecology, post-mining landscapes, nature conservation, Red List species, ecological restoration
Implications for Practice:
The trends observed in renatured and recultivated areas have significant implications for future management plans, particularly those aimed at preserving and promoting floristic and faunal biodiversity. We recommend:
- Long-term management plans are crucial for renaturation areas but not strictly necessary for recultivated sites.
- Regular mechanical disturbance should be applied in a mosaic pattern every 3–5 years.
- A variety of landscape structures should be created after the dismantling of extraction sites.
- Renaturation is preferable to recultivation for biodiversity development
How to cite: Knispel de Acosta, S.: Post-gypsum mining landscapes in Germany - Unveiling Biodiversity , EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-20330, https://doi.org/10.5194/egusphere-egu25-20330, 2025.
Posters on site: Mon, 28 Apr, 14:00–15:45 | Hall X1
Advancements in GPS radiotelemetry have facilitated the collection of extensive data on elusive wildlife species, including brown bears (Ursus arctos), for which direct observations are frequently impractical. Grounded in the premise that individual animals often exhibit temporally consistent behavioral traits, this study investigates habitat use, movement patterns, and resting behaviors of 50 brown bears inhabiting peri-urban forest ecosystems. In total, 61,562 GPS locations were recorded and linked to ecological covariates such as forest type, elevation, slope, land cover, forest biomass, deadwood availability, forest disturbance, and proximity to roads, water, impervious surfaces, and forest edges. The dataset underwent thorough cleaning to remove incomplete and erroneous points, followed by chronological ordering to capture diurnal and seasonal variability. Each location was classified into one of four seasons (winter, spring, summer, autumn) and further categorized into diel periods (dawn, day, dusk, night), adjusted according to season.
Movement analyses incorporated diel cycles, seasonal variation, sex, age, and the presence of cubs. Using clustering algorithms, we identified resting clusters and active movement segments at various spatial scales, subsequently quantifying home ranges across demographic groups and time frames. To ensure robust insights, large temporal and spatial gaps were omitted, and continuous trajectories were used to calculate key metrics, including travel time, distance, elevation change, and slope.
Mixed-effects models indicated significant seasonal and diel effects on bear velocity, with faster travel observed in summer and at dusk, and slower movement in winter and during daytime—particularly in higher-elevation and more rugged terrain. Although demographic factors (sex, age, presence of cubs) exerted limited influence on velocity itself, they were associated with variation in home range sizes and resting cluster distribution. By spatially linking GPS data and movement segments to ecological parameters, this investigation provides a comprehensive perspective on the interplay between landscape structure and bear behavior.
Through this integrative approach, our findings show both active and stationary bear behaviors in human-influenced habitats. By identifying critical periods and key habitats for resource acquisition and rest, these results may offer practical insights for conservation efforts and promote coexistence in peri-urban landscapes.
How to cite: Radu, R. G., Fedorca, M., Fedorca, A., and Petrea, S.: Coexistence Dynamics and Behavioral Analysis of Brown Bears (Ursus arctos) in Peri-Urban Forest Ecosystems, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-8555, https://doi.org/10.5194/egusphere-egu25-8555, 2025.
Ecosystem carbon pools are being rapidly transformed by global change factors (GCFs) and trophic interactions within ecosystems. However, despite mounting evidence for the individual impacts of GCFs and herbivores on ecosystem carbon pools, the extent to which these factors interact to transform ecosystem carbon dynamics remains a major uncertainty, impeding efforts to guide ecosystem-based approaches by leveraging trophic managements to climate change adaption. By curating terrestrial and aquatic GCFs and trophic interactions full-factor paired experiments globally (544 paired observations from 121 studies), we revealed that the combined effects of GCFs and herbivores on ecosystem carbon pools were more detrimental than their individual effects, and these synergistic stressors of GCFs and herbivores posited slightly different impacts on vegetation and soil carbon pools, with a more detrimental effect on plant aboveground biomass and microbial biomass carbon. Furthermore, these negative combined effects were amplified in low-latitude regions, and aridity contributed the highest power for explaining the variability in these interactions, suggesting that these effects were more likely to harm ecosystem carbon stocks in regions with higher temperatures or stronger evapotranspiration. Overall, our findings underscore that the interplay between abiotic and biotic stressors can substantially undermine ecosystem carbon sequestration capacity, particularly in already vulnerable regions, calling for a reevaluation of current climate change mitigation strategies to explicitly account for and manage trophic interactions.
How to cite: Xu, C. and Zhu, B.: Enhanced detriment to ecosystem carbon pools by global change factors and herbivory, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-7942, https://doi.org/10.5194/egusphere-egu25-7942, 2025.
Worldwide, amphibians and reptiles are among the most threatened animal classes. In Austria, more than half of the 21 amphibian and 15 reptile species are classified as endangered, critically endangered, or at risk of extinction, primarily due to habitat loss and destruction. Close to nature designed and managed gardens can serve as valuable refuges, yet they remain largely unexplored in systematic monitoring.
The “BIOM-Garten” project leverages citizen science to collect monitoring data from private properties in Austria, which are otherwise inaccessible to conservation scientists, helping to close critical gaps in amphibian and reptile monitoring. Citizen scientists use a browser-based reporting platform to submit data on species occurrence, including location, address, photos, details of sightings, and detailed descriptions of their gardens. However, inaccuracies or ambiguities in user-reported locations can hinder the scientific usability of the data.
To address these issues, we developed a workflow that integrates reported data with OpenStreetMap as well as cadastral and municipal datasets to optimize geolocation and assess data quality. By combining address information, pinned map locations, and image data of reported species recorded by cameras and mobile phones, we optimize the point location of each entry and assign uncertainty levels and a quality class to ensure scientific accuracy for subsequent environmental modeling.
In the first project year, following the platform's launch in June 2024, we received more than 700 reports. These submissions were successfully processed, geocoded, and classified, showcasing the platform's effectiveness in engaging citizen scientists and generating high-quality research data. Of the valid reported species sightings, 63% could be located at the parcel level, 29% at the municipality level, and 8% of the data had to be discarded due to insufficient localization.
How to cite: Iglseder, A., Leeb, C., Danzinger, F., Meixner, C., Linhard, D., Lettner, C., and Hollaus, M.: Closing Biodiversity Monitoring Gaps: A Workflow for Validation and Quality Assessment of Citizen Science Location Data for Amphibian and Reptile Monitoring in Private Gardens , EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-9242, https://doi.org/10.5194/egusphere-egu25-9242, 2025.
Rewilding has emerged as a transformative restoration approach, promoting ecosystem self-regulation by restoring key processes like trophic complexity and reducing human influence. As a nature-based solution, rewilding plays a vital role in both climate adaptation and mitigation, offering pathways to address challenges like biodiversity loss and carbon sequestration. Trophic rewilding, in particular, focuses on reintroducing keystone species such as large herbivores to restore ecosystem functionality. While rewilding's impacts on biodiversity and aboveground carbon dynamics are increasingly documented, its influence on soil carbon storage—particularly the underlying dynamics—remains poorly understood. Large herbivores can influence soil carbon both directly and indirectly through mechanisms such as trampling, defoliation, and defecation. Trampling alters soil bulk density and porosity, affecting soil aeration and microbial activity. Defoliation simulates biomass removal, redistributing aboveground carbon inputs to the soil. Defecation contributes to nutrient cycling and modifies the C/N ratio in soils. Despite observational studies, laboratory experiments, and meta-analyses pointing to these mechanisms, there is a lack of comprehensive modeling frameworks to capture their cumulative effects on soil carbon dynamics.
Here we used LPJ-GUESS, a dynamic vegetation model (DGVM), to simulate rewilding scenarios across Europe, from single points to regions. The point estimates are based on data from sites in Poland and Denmark; the Białowieża Forest (BIA) in Eastern Poland, one of Europe's last lowland primeval forests, where 23 years of herbivore exclusion has allowed undisturbed regeneration within fenced areas, and the Mols Laboratory (ML), a former agricultural landscape in Denmark rewilded since 2016. These sites represent two stages of a ‘Northern European rewilding trajectory’: BIA as a late-successional system, and ML as a system in a state of early secondary succession. Preliminary results indicate that the model performs well in simulating single-point scenarios of passive rewilding and realistic land-use and land-cover changes (LUCC). Comparisons with global MODIS and FLUXNET-derived daily GPP data yield R² values of 0.86 for Białowieża and 0.84 for Mols.
Building on this, we aim to enhance LPJ-GUESS by representing animal-driven processes such as trampling, defoliation, and defecation in the model, to compare the impact of trophic (animal introductions) and passive rewilding (land abandonment), continued agriculture, and traditional grassland nature management (mowing) on carbon dynamics. Future work will explore the regional impacts of large herbivores on soil carbon dynamics and greenhouse gas fluxes through advanced modeling and field data integration. This research will contribute to understanding the role of large herbivores in ecosystem restoration and carbon cycling, supporting the emerging discipline of zoogeoscience.
How to cite: Cheng, Y., Kristensen, J. A., Roux, L. L., Philipsen, F. N., Keeffe, J. O., Larsen, K. S., Müller, C. W., Christiansen, J. R., and Vesterdal, L.: Modeling the effects of rewilding on soil carbon dynamics and greenhouse gas mitigation in Europe, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-11704, https://doi.org/10.5194/egusphere-egu25-11704, 2025.
Globally, the encroachment of human activities on protected areas is accelerating, posing new challenges for biodiversity conservation. As the United Nations’ 2030 goal of protecting 30% of the planet's landmass for nature draws closer, understanding the lesser-known dimensions of human disturbances becomes critical. Anthropogenic seismic noise, such as that produced by mining, oil drilling, and heavy infrastructure development, represents a largely unexplored but potentially substantial threat to sensitive ecosystems. Recent studies have revealed that large mammals, including elephants, are sensitive to seismic waves, detecting seismic signals and potentially using them for long-distance communication.
This research explores the interplay between seismology and conservation biology by investigating the impact of seismic noise from extractive operations on wildlife spatial behavior and habitat use in Murchison Falls National Park, Uganda. Using seismometers, camera traps, and machine learning models, this study uncovers correlations between seismic activity patterns and shifts in large mammal movements. The findings highlight how seismic disturbances propagate into wildlife behavior, contributing to an emerging understanding of how human activities affect ecosystems beyond visible or audible dimensions. By bridging the fields of geophysics and biodiversity conservation, this research underscores the need for holistic environmental impact assessments in protected areas and provides a foundation for mitigating seismic noise effects on biodiversity.
How to cite: Boudinot, L., Lecocq, T., Almasri, F., Koelemeijer, P., Montgomery, R., and Mortimer, B.: Assessing the Impact of Anthropogenic Seismic Activity on Wildlife in Protected Areas, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-20230, https://doi.org/10.5194/egusphere-egu25-20230, 2025.
Nature-based solutions to climate change, e.g. restoring ecosystem processes that translocate GHG from the atmosphere to biomass, are recognized as cost-effective methods to simultaneously mitigate climate change and reverse ecosystem degradation. The importance of large ungulates as part of nature-based solutions has been emphasized due to their critical role in maintaining and improving diversity in ecosystems, while the extent of large ungulate-mediated effects on radiative forcing and greenhouse gas balance is unclear due to lack of observations and apparent context-dependencies across biomes. We particularly lack direct measurements of large ungulate-mediated feedbacks on soil GHG fluxes despite their substantial influence on atmospheric concentrations of GHG’s. Large ungulates shape their environments e.g. via biomass consumption, alteration and redistribution, seed dispersal and trampling, affecting plant diversity and productivity as well as soil physicochemical conditions. Together, these impacts may govern the direction and magnitude of soil GHG fluxes.
Here, we present a study conducted in a Danish rewilding area, where cattle and horses were released for year-round grazing in 2016. Within the 120 ha area, we studied eight fenced experimental blocks located in common broom (Cytisus scoparius) dominated shrublands on well-drained sandy soils. We aimed to detect effects of three treatments resembling possible nature management strategies: Trophic rewilding (large ungulate presence) passive rewilding (large ungulate absence) and annual mowing (traditional nature management) on soil GHG fluxes. We were particularly interested in identifying the ungulate-mediated effects on soil physicochemical parameters that drive soil GHG fluxes. Our experimental approach included both chamber measurements in the field and laboratory incubations of intact soil cores. During both types of campaigns, we measured fluxes of CO2, CH4 and N2O. To elucidate mechanistic relationships, we also measured soil parameters related to physical structure, soil C & N concentrations, and N mineralization rates.
Initial results from our incubation experiment suggest that trophic rewilding increased soil respiration, which is in contrast to field measurements that showed higher respiration rates from passive rewilding plots. The former result may be attributed to higher soil C concentrations under trophic rewilding, and the latter to greater autotrophic respiration under passive rewilding. Conversely, CH4 uptake rates and N2O emissions were reduced under trophic rewilding, which could partially be explained by changes soil structure and nitrification rates. Annual mowing management exhibited similar responses in CO2 and CH4 fluxes to trophic rewilding, while the production of N2O was substantially reduced compared to the other management types. Our study demonstrates that introducing large ungulates in nature management may influence soil GHG fluxes, highlighting their role in soil biogeochemical processes and nature-based climate solutions.
How to cite: Philipsen, F. N., O'Keeffe, J., Larsen, K. S., Kristensen, J. A., Le Roux, E., Cheng, Y., Müller, C. W., Vesterdal, L., and Christiansen, J. R.: Effects of different nature management strategies on soil GHG fluxes: Trophic rewilding, passive rewilding and mowing, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-17711, https://doi.org/10.5194/egusphere-egu25-17711, 2025.
Evaluating how land cover is being transformed is essential to identify patterns necessary to infer the change trajectories and the driving factors. This study considers the case of Nigeria, where various natural ecosystems are being converted and for which a current national scale assessment at high spatial resolution is lacking. Producing 30 m Landsat-based time-series data, we analyze change among land cover types (i.e. tree-covered area, grassland, wetland, waterbody, cropland, artificial surface, and otherland) across seven agroecological zones. The annual change intensity was assessed at multi-levels across three time-intervals (i.e. 1986-2000, 2000–2013, 2013–2022). Distinguishing between natural land cover and human activity-related land-use, we estimate the extent of change signifying how humans have appropriated natural land cover (HANLC) over almost four decades. Focusing on major processes of observed change patterns, transitions between categories were aggregated into three HANLC classes for each time point (i.e. 1986, 2000, 2013, 2022). The HANLC classes are: 1) Cropland expansion, 2) Settlement and infrastructure development (SID), and 3) Natural regeneration and afforestation (NRA) comprising areas of NLC recovery. The first and second classes are areas where HLU expanded into NLCs. We then estimated the extent and changes of HANLC during the three time-intervals. The latter formed the basis for identifying the drivers and processes underlying the observed HANLC changes across AEZ and at the national level.
Insights from analysis at the interval level reveal that land transformation accelerated from 2.7% yr−1 during 1986 – 2000 to 3.3% yr−1 during 2000 – 2013 and peaked at 4.5% yr−1 during 2013 – 2022 in all agroecological zones (e.g. rainforest, mangrove), except in Sudan savannah and Sahel savannah where speed was higher in 2000–2013 as grasslands were increasingly cultivated. Cropland expanded almost two-fold (22% to 37%), whereas tree-cover declined from 50% to 31% and wetland from 7% to 3.7% over the 23 years. Much loss of natural land cover (e.g. tree-cover, grassland, and wetland) to cropland occurred in 2000–2013 (22%) when most irrigation schemes in Nigeria were established. In contrast, the loss of mostly natural land cover to settlement (0.6%) during 1986 – 2000 increased to 0.9% in 2000–2013 and to 2.0% in 2013–2022. Of all agroecological zones, the mangrove zone was most disturbed as its persisting land cover areas reduced from about 80% during 1986 – 2000 to 69% in 2000–2013 and to 5% in 2013–2022. The amount of persisting land cover increased in the Sudan savannah at 16% in 1986 – 2000, 44% in 2000–2013 and 49% in 2013–2022. Processes of human-appropriated natural land cover in Nigeria are related to urbanization and cropland expansion into natural areas with some instances of natural regeneration, especially in croplands and abandoned settlement areas. Studies to identify measures to halt the high rate of conversion of natural land covers to croplands are thus needed.
Relevant links:
- https://doi.org/10.1080/10095020.2024.2362759
- https://zenodo.org/doi/10.5281/zenodo.8205098
How to cite: Akinyemi, F. O. and Ifejika Speranza, C.: Human-appropriated natural land cover in Nigeria are related to urbanization and cropland expansion from 1986 to 2022, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-13362, https://doi.org/10.5194/egusphere-egu25-13362, 2025.
Soil fauna, particularly its microarthropod content, is key to soil functioning. However, the interactions of agricultural practices and the functioning of its soil biodiversity are not fully understood. We evaluated how vegetation cover affects microarthropod diversity in three Mediterranean agroecosystems - almond and olive orchards and a vineyard in Israel. Soil samples were collected from vegetated and non-vegetated areas and analyzed using the Soil Biological Quality method (QBS-ar). Higher QBS-ar, higher microarthropod richness, and distinct assemblage composition were measured in vegetated soils compared to soils without vegetation. Acari, Collembola, Diplura, Coleoptera, Chilopoda, and Symphyla were identified by indicator value analysis as biological indicators of vegetation cover. These findings highlight the positive impact of vegetation cover on soil biodiversity in agroecosystems, which is likely to support ecosystem services. Such research can aid Mediterranean farmers, land managers, and policymakers develop sustainable soil management practices that balance biodiversity conservation with agricultural productivity. Developing soil fauna bioindicators and indexes can be essential to monitoring soil status. Such monitoring tools can support establishing solid scientific knowledge to inform practitioners and policymakers on how to implement sustainable management solutions.
How to cite: Shelef, O., Tadesse, Z., Fireman, J., Belayneh, R., and Coll, M.: Aboveground Vegetation and Soil Fauna Activity - Land Use effects on Soil Biodiversity, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-16310, https://doi.org/10.5194/egusphere-egu25-16310, 2025.
Biodiversity degradation in intensive agricultural landscapes has been a pressing issue, as agricultural systems cover a significant portion of land and greatly influence habitats crucial for species diversity. Understanding the impact of historical agricultural land use on recent biodiversity is essential to uncovering legacy effects and developing strategies for ecological restoration and long-term sustainability. Plant diversity is critical for maintaining ecosystem functionality, enhancing resilience, and supporting sustainable agriculture. However, the extent to which agricultural intensification has impacted biodiversity remains poorly quantified. This study investigates how historical land-use changes have influenced biodiversity in Denmark by combining historical land-use data with records from Flora Danica, a comprehensive dataset documenting the occurrence and distribution of Danish plants. By analysing spatial and temporal patterns, we aim to address the effect of agricultural intensification and land-use changes on recent biodiversity patterns or biodiversity richness.
The research explores the legacy effects of historical agricultural land use at selected hotspots of change and how these insights can inform sustainable future management practices and biodiversity restoration. Our approach provides a unique opportunity to link historical developments with present-day biodiversity richness – or poorness offering valuable knowledge on the timeframes of degradation and potential restoration. These findings are crucial for addressing contemporary challenges in biodiversity conservation and sustainability. This study emphasises the importance of historical perspectives in ecological research and highlights the need for integrative approaches to safeguard biodiversity in agricultural landscapes.
How to cite: Lohrum, N., Storgaard Danielsen, A.-C., Graversgaard, M., Normand, S., and Dalgaard, T.: From Fields to Flora: Decoding Historical Land-Use Intensification and Its Impact on Danish Plant Biodiversity, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-17877, https://doi.org/10.5194/egusphere-egu25-17877, 2025.
Posters virtual: Thu, 1 May, 14:00–15:45 | vPoster spot 2
EGU25-6325 | ECS | Posters virtual | VPS29
The different responses of planktonic bacteria and archaea to water temperature maintain the stability of their community diversity in dammed riversThu, 01 May, 14:00–15:45 (CEST) | vP2.5
Planktonic bacteria and archaea play a key role in river nutrient biogeochemical cycling; however, their respective community assembly and how to maintain their diversity are not well know in dammed rivers. Therefore, a seasonal survey of planktonic bacterial and archaeal community compositions and related environmental factors was conducted in 16 cascade reservoirs on the Wujiang River and the Pearl River in southwest China to understand the above mechanisms. The result showed that deterministic processes dominated bacterial and archaeal community assembly. Planktonic bacteria and archaea in dammed rivers had different biogeographic distributions, and water temperature was a key controlling factor. Water temperature can directly or indirectly affect the microbial diversity. Planktonic bacterial diversity increased with increasing water temperature, while archaea showed the opposite trend; the overall diversity of bacteria and archaea was no significant changes with changeable water temperature. Abundant microbes had a stronger distance-decay relationship than middle and rare ones, and the relationship was stronger in winter and spring than in summer and autumn. The different responses of planktonic bacterial and archaeal diversity to water temperature could be due to their different phylogenetic diversity. This ultimately maintained the stability of total microbial community diversity. This study reveals the different responses of planktonic bacteria and archaea to water temperature and perfects the theoretical framework for planktonic microbial biogeography in dammed rivers.
How to cite: Liu, N., Wang, B., and Yang, M.: The different responses of planktonic bacteria and archaea to water temperature maintain the stability of their community diversity in dammed rivers, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-6325, https://doi.org/10.5194/egusphere-egu25-6325, 2025.
