Human influence on geomorphic systems is now nearly ubiquitous, exceeding previous periods in scale, intensity, and spatial reach. At the same time, biotic–abiotic feedbacks, geodiversity, and long-term landscape evolution continuously shape ecosystems and societies. This interdisciplinary session provides a platform to examine these connections and strengthen geomorphology’s contribution to Anthropocene research.
Contributions address humans as agents of geomorphic change across all process domains, including direct interventions such as construction, river engineering, and land-use change, as well as indirect drivers like climate change. A central focus is a biogeomorphic perspective that links ecological processes with erosion, transport, and deposition. By analyzing two-way interactions between organisms and landforms - from individual plants to catchments, and from event-scale disturbances to millennial evolution - studies explore how ecosystem–landform feedbacks generate emergent patterns and trajectories. Approaches span fundamental process research, experimental and field studies, remote sensing, and integrative modelling that connect multi-scale observations to conceptual advances. Applications in nature-based solutions, hazard mitigation, and sustainable land and water management are also considered.
The session further addresses the need to assess and manage risks to geodiversity and geoheritage under growing anthropogenic and climatic pressures. Topics include methodological advances for identifying, evaluating, and monitoring threats across urban, rural, mountain, and coastal settings, as well as tools for geoconservation, geoeducation, geodiversity action planning, and community engagement.
Finally, the session highlights the dual role of surface processes as both sustaining and disruptive forces. Weathering, soil formation, and sediment redistribution support habitats and nutrient cycles, while gradual yet pervasive changes can act as “silent disasters” with cascading effects on biodiversity and human well-being.
Orals: Thu, 7 May, 14:00–18:00 | Room G1
Geodiversity and, geoheritage deliver services and benefits for people and nature through the influence of geology, geomorphology soils, hydrology and biogeochemical processes on landscape, habitats and species, ecosystem functioning, economic activities, historical and cultural heritage and people’s health and well-being. However, direct and indirect impacts of human activities present huge challenges both globally and locally for geoconservation in protected and conserved areas. Regardless of how one defines the Anthropocene, human activities have progressively transformed the planet, culminating in the Great Acceleration from the 1950s onwards. Threats arise from urban and infrastructure development, mining and mineral extraction, land restoration, changes in land use, river and coastal management, recreation and tourism. Moreover, these are compounded by the impacts of climate change and sea-level rise. Inventories and assessments of geoheritage sites important for research, education and geotourism have been a prominent focus of geoconservation work, but there has been less emphasis on site management aspects of geoconservation in the face of these threats, particularly the opportunities for proactive management. Protected and conserved areas have a vital part to play in geoconservation but in order to prioritise and target resources effectively, more strategic approaches are required, moving forward from reactive management to planning and preparing for changes and impacts. Based on common standards and definitions, adapted as necessary for local circumstances, there is a need for systematic risk and vulnerability assessments, development of adaptation responses, monitoring and management planning based on understanding geomorphological processes and landscape evolution as part of a more integrated approach to nature conservation that recognises the links between geodiversity and biodiversity. This is particularly timely in the context of the new IUCN programme on Key Geoheritage Areas and their potential links with Key Biodiversity Areas. A management framework for climate change risk assessment and adaptation planning for geoheritage sites is used to illustrate such an approach.
How to cite: Gordon, J. E. and Wignall, R. M. L.: Framing geoheritage management responses to threats in the Anthropocene: moving from reactive management to prioritising risk-based planning , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-8200, https://doi.org/10.5194/egusphere-egu26-8200, 2026.
Geodiversity and geoheritage face increasing pressures from both natural and anthropogenic threats, including inadequate site management, the cumulative effects of infrastructure development, and natural erosion. Geotourism, if not strategically managed, may pose significant threats to geoheritage. However, when properly planned, it plays a crucial role in fostering local sustainable development, increasing the visibility of geoheritage, and promoting geoconservation awareness.
In this context, we present a methodology designed to support the development of strategies for the sustainable management of geosites as tourism resource, ensuring their protection while enhancing their scientific and cultural value. The methodology consists of three main phases and is particularly suitable for territories aiming to strengthen their geotourism strategies or valorize their geoheritage, including geoparks, aspiring geoparks, Key Geoheritage Areas (KGA), and protected areas.
The first phase includes a qualitative assessment of Touristic Potential (TP), aimed at identifying geosites with the greatest potential to be used as tourism destinations of an area. The TP assessment is based on four qualitative criteria: scenery, observation conditions, interpretative potential, and accessibility. The second phase focuses on the identification and evaluation of threats to geoheritage at the geopark scale through a risk assessment matrix, which supports the prioritization of management actions. Finally, the third phase introduces a user-friendly Degradation Risk (DR) assessment tool, developed considering existing methodologies and structured around four core components: sensitivity (SS; 3 criteria), visitor pressure (VP; 5 criteria), protection measures (PM; 3 criteria), and magnitude of loss (ML; 1 criterion). Each criterion is evaluated using a point-based system, and the total DR score is calculated using the formula:
DR = (SS + VP + PM) × ML.
This methodology was tested in the Beigua UNESCO Global Geopark (NW Italy), an area characterized by high geodiversity and contrasting patterns of tourist pressure between the coastal watershed and inland sectors. The application of this methodology first enabled the identification of geosites with high touristic potential; subsequently, a targeted assessment was carried out on the ten most frequently visited geosites to evaluate the method under conditions of higher visitor pressure. The results highlighted the main threats affecting the geopark’s geoheritage as well as the varying degrees of degradation risk among geosites. Moreover, the interpretation of results allowed the identification of the components that mostly contribute to the total DR and the most appropriate management strategies for each site, supporting the development of a sustainable geotourism model tailored to local needs. This integrative method can serve as a practical and flexible tool, ensuring that geotourism becomes a driver for territorial development and geological literacy rather than a threat to geoheritage.
How to cite: Gianoglio, F. and Marescotti, P.: Geotourism between opportunity and threat: a new methodology for geosites assessessment and sustainable management strategies, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-471, https://doi.org/10.5194/egusphere-egu26-471, 2026.
Urban subterranean geosites are among the most fragile elements of geoheritage because limited underground space is highly sensitive to human-induced impacts. Medova Cave, situated within the city limits of Lviv (Western Ukraine), is a small multi-chamber karst cavity developed in Badenian Ratin limestones. For decades, it has been used for student training and casual public visits. Although the site holds a local protection status, ongoing visible deterioration indicates the absence of effective management. The main degrading factors include unregulated access, surface and subsurface vandalism, littering, occasional shelter use, and microclimatic disturbance linked to proximity to urban infrastructure.
This study presents a combined assessment of the geoheritage value and the current risk level of Medova Cave, focusing on the challenges of managing geodiversity within a large urban environment. The geoheritage appraisal follows the criteria proposed by Brilha (2015), including: • scientific value — a representative example of shallow karstification on the southwestern border of the East European Platform;
• educational value — long-term use as a natural field classroom in a major academic center; • cultural and historical relevance — documented public visitation since the pre-WWII period;
• representativeness — one of the very few urban caves in Western Ukraine;
• integrity — moderate and declining, but still allowing meaningful interpretation.
Risk was evaluated via a semi-quantitative matrix adapted from recent geomorphosite vulnerability research (e.g., Kubalíková, 2024). Intensity and likelihood were rated on a five-point scale for seven hazard groups: natural instability, mechanical damage, informal shelter use, unregulated visitation, microclimatic alterations, governance deficiencies, and surrounding urban pressures. The highest risk score is linked to governance deficiencies (R = 25), indicating that degradation results from the lack of management rather than isolated incidents. The next-highest risks are mechanical damage (R = 16) and unregulated visitation (R = 15). Natural and chemical impacts currently remain secondary but tend to increase as uncontrolled access persists.
The results demonstrate that Medova Cave is undergoing active, cumulative degradation, a pattern commonly observed at protected sites where no practical conservation measures are implemented. Despite this, the cave still preserves a level of scientific readability and educational usability, meaning that protective action can still reverse negative dynamics. Simple low-intervention measures — such as controlled entry, marked routes, informational signage, regular inspections, and partial buffering of surface impacts — could slow degradation while maintaining educational use.
Overall, the Medova Cave case underscores the importance of considering management effectiveness as a primary driver of risk in urban geoheritage. In underground environments within cities, degradation rarely stems from a single event; instead, it is the outcome of prolonged permissive access and absence of responsibility for site condition. Addressing this systemic factor is essential for conserving fragile subterranean geodiversity in expanding urban areas.
How to cite: Bubniak, I., Bubniak, A., Vivat, A., and Marko, T.: Geoheritage Values and Risk Assessment of Medova Cave in Urban Lviv (Ukraine), EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-604, https://doi.org/10.5194/egusphere-egu26-604, 2026.
The increasing pressure from climate‑driven and human‑induced disturbances in high-latitude regions has created an urgent need for novel approaches to support existing conservation strategies. The development and utilization of new approaches could be particularly useful in investigating and conserving Arctic and sub-Arctic environments, which are among the most vulnerable to ongoing climate change. The integration of geodiversity information, i.e., the diversity of abiotic features in the Earth surface and subsurface, into environmental research offers high potential for assessing risks to geodiversity and ecosystems.
Varying definitions of geodiversity complicate mapping and analysis efforts, and holistic measures and monitoring schemes of geodiversity are yet to be developed. The fundamental issue in mapping geodiversity is the need to categorize objects into distinct classes that can be judged to be distinctive. To address categorical inconsistency in geodiversity data, Hjort et al. (2024) proposed a hierarchical taxonomy of geodiversity, in which geological (rocks, tectonics) geomorphological (landforms, Earth surface processes), pedological (soil pedons and materials) and hydrological (surface and subsurface water features) components of geodiversity are classified based on their genesis, physico-chemical properties and morphology.
This study uses the proposed taxonomy of geodiversity under field conditions to test its applicability in identifying high-value geodiversity areas. Our main goals were to 1) conduct a holistic geodiversity mapping across a spatially extensive and diverse environment, and 2) explore the spatial distribution of geodiversity and its components. Field work was conducted at 192 study sites using 5- and 20-meter survey radii to map geofeatures in a sub-Arctic environment in northern Finland characterized by a complex glacial footprint and diverse ecological conditions. Overall, 180 different geofeatures were mapped. On average, survey sites contained 17 geofeatures, while the most geodiverse sites hosted up to 30. Thematically detailed information on fine-scale geodiversity can improve our understanding of high-latitude geodiversity, inform geoconservation efforts, and serve as a tool for identifying and monitoring environmental change.
References
Hjort, J., Seijmonsbergen, A. C., Kemppinen, J., Tukiainen, H., Maliniemi, T., Gordon, J. E., Alahuhta, J., and Gray, M.: Towards a taxonomy of geodiversity, Philosophical Transactions A Mathematical, Physical and Engineering Sciences, 382, 20230060, https://doi.org/10.1098/rsta.2023.0060, 2024.
How to cite: Karjalainen, O., Maliniemi, T., Riikonen, A.-M., and Hjort, J.: Local-scale field mapping of geodiversity: a case study from sub-Arctic Finland , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-17810, https://doi.org/10.5194/egusphere-egu26-17810, 2026.
On September 19th, 2021, the last eruption from the Canarian archipelago began on La Palma island. The youngest Spanish volcano, called Tajogaite, produced one of the most complex and extensive lava field ever documented in the Canary Islands. The eruption was a multi-vent fissural eruption with effusive and explosive volcanic activity. With a mean discharge rate of 32.7m3s-1, the Tajogaite volcano emitted 242m3 of volcanic material (Calvari et al., 2026) and covered 1.219e+7m2 of surface with lava flows. The socioeconomic impact resulted in 3.7e+6m2 of cropped area, 3126 edifices, including 75 industrial facilities, 5445 parcels, and 92 km of roads destroyed (Copernicus EMS. https://emergency.copernicus.eu/; BOPC núm.533,14/12/2022). After the eruption, recovery and rehabilitation of the affected areas became challenging, being mainly focused on demolition and clearing land projects. However, this eruption has highlighted the scientific challenge of determining the most valuable volcanic features for protection (Vegas et al., 2022). To ensure a sustainable development of land recovery, the Geological and Mining Institute of Spain (IGME-CSIC) made a fast-response report to the regional authorities with an integral geoheritage assessment and mapping of the most valuable volcanic elements that should be included in the new regional legislation, including precautionary measures for conservation of the best geoheritage elements of this volcano.
Geoheritage mapping was carried out in 2022 through the integration of high-resolution satellite imagery, drone-based photogrammetry, and fieldwork observations. The resulting products included: (1) initial request for the expansion of the Natural Protected Areas of Cumbre Vieja, consisting in one map with three areas of ∼311ha with high scientific value, 10 maps with the scientific, touristic and fragility values and 34 types of Elements of Volcanic Interest (EVI), representing the first approach of a detailed official quantitative value of Tajogaite volcano; (2) A new geoheritage methodology developed for the Tajogaite eruption in accordance with the IELIG and the Spanish Law.42/2007 “on the natural heritage and biodiversity”.
The EVIs were identified based on morphological, textural, lava flow margins and lava tube-related structures. A special case of this eruption is the network of lava tubes that played a unique role transporting lava flows over long distances (Sanz-Mangas et al., 2025), allowing sustained advance to the coast. Due to their unique features, these EVIs have a high potential for research and geotourism. While post-eruption reconstruction is essential for the recovery and well-being of the affected communities, the irreversible destruction of many of the most valuable EVI, still not declared protected natural areas by the Canary Islands Government, has led to the loss of a unique volcanic landscape, hindering scientific progress and limiting future opportunities for society to benefit from this geoheritage.
Calvari et al. (2026). Bulletin of Volcanology, 88,8. https://doi.org/10.1007/s00445-025-01925-x
Sanz-Mangas et al. (2022). Cosmológica, ISSN 2792-7423, p113-115
Vegas et al. (2022). Official Report “Propuesta de Protección de los Elementos de Interés Geológico para el Territorio Afectado por la Erupción de 2021”. Unpublished.
Acknowledgements
This project was developed under the Sub-Project 1 ‘Canary Islands, destiny of Volcanoes’ funded by PROMOTUR Turismo Canarias,S.A. through Next Generation EU-funds, PRTR. 2024krQ00nnn; and MITECO (227G0165-GEOPALMA).
How to cite: Sanz-Mangas, D., Vegas, J., Lozano, G., Ferrer, N., Sánchez, N., and Galindo, I.: Applying the Spanish Inventory of Sites of Geological Interest (IELIG) to the 2021 Tajogaite Eruption: Insights and Lessons Learned, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-11595, https://doi.org/10.5194/egusphere-egu26-11595, 2026.
This study presents the selection and assessment of 13 geological sites in the municipalities of Elche and Alicante (Valencian Community, SE Spain), representative of sedimentary and palaeoenvironmental processes within the Bajo Segura basin linked to the Messinian Salinity Crisis (MSC). This assessment was made using the FOPALI (Fossils and Heritage of Alicante) method, which integrates scientific value, potential use and deterioration risk criteria, thus allowing for an objective and comparative evaluation of the vulnerability and risk factors affecting each site.
The results reveal that the outcrops possess high scientific significance due to the remarkable preservation of fossils and key stratigraphic records, as well as strong potential for educational programmes, public outreach, and geotourism. However, these sites are exposed to both natural and anthropogenic threats, including erosion processes, urban expansion, infrastructural development, insufficient legal protection, and incompatible land use. This compromises their integrity and long-term preservation and highlights the urgent need for proactive conservation strategies.
Overall, this study emphasizes the significance and vulnerability of the MSC-related geological heritage, which is included within a legally recognized context of international relevance (Act 42/2007, December 13, on Natural Heritage and Biodiversity). Beyond scientific analysis, the project aims to foster a sense of territorial identity rooted in the shared geological history of Elche and Alicante. By identifying the main risk factors, it provides a foundation for the development of strategies and practical approaches towards its conservation and sustainable use, contributing to both scientific knowledge and the education and awareness of the wider public.
How to cite: Corbalán Andreu, C., Fierro Bandera, I., Brilha, J., and Aberasturi Rodríguez, A.: Risk assessment of Miocene – Pliocene geoheritage in SE Spain: the Reef Project, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-8079, https://doi.org/10.5194/egusphere-egu26-8079, 2026.
Geodiversity assessment is increasingly recognised as a practical and effective tool supporting the identification, management and monitoring of areas of high natural value, particularly in the context of growing environmental pressures and threats to geoheritage. This presentation has a methodological focus and aims to introduce two geodiversity assessment methods as decision-support tools for identifying the most valuable parts of protected and conserved areas (PCAs), as well as for assessing the rate of change in geodiversity value within a selected study area.
The proposed methods are suitable for the assessment of geo(morpho)sites with a defined area characterised by geomorphometric and geomorphogenetic diversity. They are not intended for the evaluation of point-scale geoheritage features, such as rock outcrops, erratic boulders, caves or waterfalls. Both approaches belong to qualitative–quantitative geodiversity assessment methods and are based on spatial multi-criteria analysis (S-MCA). The first method is designed primarily to identify areas of exceptionally high geodiversity value. It integrates direct spatial data, including geological, geomorphological and soil maps, with indirect variables derived from a Digital Elevation Model (DEM), such as relief energy, the topographic wetness index, total solar radiation and other terrain-based parameters. This approach has proven particularly effective for spatial prioritisation and for supporting geoconservation planning and management. The case studies include established protected areas, such as geomorphosites (Illgraben and Derborence in Switzerland) and a national park (Karkonoski NP in Poland).
The second method relies exclusively on indirect data, specifically geomorphometric parameters calculated from high-resolution LiDAR-derived Digital Elevation Models. The availability of very detailed and up-to-date terrain models allows not only the assessment of present-day geodiversity patterns, but also the identification of temporal changes in geodiversity. This dynamic perspective provides valuable input for risk assessment by enabling the detection of areas undergoing rapid geomorphological change and therefore potentially exposed to increasing threats. The method is demonstrated using a designated nature reserve (Morasko Reserve in Poland) and, for comparison, a dynamically developing urban area under strong anthropogenic pressure.
The applicability of the proposed methods is primarily limited by the availability of spatial data with appropriate temporal and spatial resolution. Both approaches allow for the identification of areas with high geodiversity value and provide a solid basis for management decisions. For these areas, risk assessment can be conducted and strategies for the protection and sustainable management of geoheritage can be developed.
How to cite: Najwer, A.: Geodiversity assessment as a practical tool for risk identification, monitoring and management, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-18664, https://doi.org/10.5194/egusphere-egu26-18664, 2026.
The Elster-Pleiße floodplain south of Leipzig has undergone significant hydromorphological changes over the past few centuries, influenced by both natural processes and anthropogenic interventions (e.g. characterized by the repurposing of former river courses into mill races and other engineered water-management channels). This study employs selected mapping of fluvial-geomorphological features based on a LiDAR DTM (Light Detection and Ranging Digital Terrain Model; 1 x 1 m resolution) and old maps analyses to reconstruct past river dynamics and identify shifts in channel morphology. Geomorphological features, such as oxbows, ridge-and-swale point bar structures, crevasse splays and levees reveal an earlier, more dynamic floodplain characterized by meandering and anabranching channels, which transitioned into a system of stabilized, largely immobile watercourses. Comparative analyses of old maps spanning from the 16th to the 20th century indicate a gradual reduction in river sinuosity and lateral migration, coinciding with increasing human modifications such as mill races, timber rafting canals, and flood protection measures. Key transformations include the straightening of channels, floodplain aggradation, and the impact of open-cast lignite mining in recent centuries. The study highlights the complex interplay of sedimentary processes and anthropogenic activities in shaping the floodplain's evolution. This combined approach allows for a detailed examination of the relative chronology of changes and helps identify topographic legacies left by dynamic floodplain systems, enhancing our understanding of the evolution of these landscapes. Understanding these long-term dynamics provides crucial insights for contemporary river restoration and flood management strategies.
How to cite: Schmidt, J., Lindemann, S., Geißler, F., Hein, M., Lohse, N., Schmidt-Funke, J., and Hardt, M.: Spatiotemporal dynamics of river channel patterns during the last 400 years in Central Germany, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-7094, https://doi.org/10.5194/egusphere-egu26-7094, 2026.
The burgeoning demand for construction materials has led to marked increase in riverbed sand mining in eastern India, particularly through mechanized means. Such mining occurs within the river channel (via dredging) and especially over the exposed sand bars during the low-flow period. This has created a new class of anthropogeomorphic landforms that have seldom been documented before. Such ‘montanogenic’ features were mapped along several rivers of the region from historical and present-day Google Earth images during the period 2016–2024 and classified as sand hollows, sand pools, sand tracks/roads and sand mounds. The identified landforms primarily vary based on the river width, and history and regularity of sand mining in the examined river reaches. Their spatial distribution, hotspots of occurrence, patterns and association were also ascertained. Such multi-temporal analysis highlights the marked growth of sand pools due to continual extraction and the prevalence of more extensive mining regimes in recent times. For example, along the Subarnarekha River, sand pools increased in number by almost five times between 2020 to 2022, while their total areal coverage rose from 7650 m2 to 22477 m2, almost tripling in extent. The seasonal growth of sand roads reveals the progress of the mining season, which typically occurs from late-October to early-June, encompassing the post-monsoon to summer period. High-resolution DEMs from Cartosat-1 stereo images and repeat UAV surveys were used to discern volumetric changes in mined river reaches using the DEM-of-Difference (DoD) approach and assess sediment replenishment and extraction. Generation of Relative Elevation Models (REMs) further revealed the channel morphological alterations induced by mining, while hydraulic simulations (HEC-RAS 1-D) highlighted the alterations in instream flow patterns and velocities within mining sites, in comparison to that in unaffected river reaches. The cumulative effect of such riverbed mining activity is to markedly alter the channel planform morphology. Parameters like Degraded to Active Channel Ratio (DACR), Channel Belt Width (CBW), and Erosion-Deposition Index (E-D Index) were enumerated reach-wise for the examined rivers using high-resolution Resourcesat series LISS-IV MX images to highlight the above channel changes, along with measurement of river centerline and bankline shifts induced by mining. Such channel morphological alterations also change the river’s ecological character, particularly during the peak sand mining period in January–February, when mined river stretches reported high total suspended sediment (TSS) values ranging from 150-350 mg/L, notably in excess of specified standards by India’s Central Pollution Control Board. The extensively mined Damodar River was the most affected in this regard. In contrast, the unaffected reaches of these rivers reported far lower TSS values around 50 mg/L. Sand pools had even higher turbidity levels, regularly reporting TSS values higher than 500 mg/L, denoting hostile conditions for fishes and macroinvertebrate species, and their drying out and disconnection from the river results in the death of trapped fishes. Continued sand mining also exposes coarser substrates on the riverbed, due to removal of finer sand deposits, thereby potentially altering instream habitat conditions. Repeated monitoring of such riverbed mining is thus essential for framing reach restoration guidelines.
How to cite: Patel, P. P., Gupta, S., Ghosh, T., Sarkar, J., and Bhowmick, P.: Gutting the innards: how riverbed sand mining is altering channel morphology, changing ecological conditions and creating new anthropogeomorphic landforms along eastern India’s rivers, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-832, https://doi.org/10.5194/egusphere-egu26-832, 2026.
It was first hypothesised by Church and Ryder (1972) that when a glaciated basin starts to witness declining glacier cover there would be an initial increase in sediment yield associated with enhanced glacier melt and sediment transport and also a landscape response as newly exposed sediment is reworked. This would reach a peak and then decline as glacial erosion and sediment transport capacity decline and the landscape slowly stabilises. The implicit assumption is that this is a transient response from an ice-erosion dominated landscape to a rainfall-erosion dominated landscape and is manifest as a period of “peak sediment” yield. In theory, due to rapid climate warming, we are now in that phase of transience but there are no datasets that describe it, we have little idea at whether peak sediment has been reached or passed, nor how this may vary between river basins with different altitudes, lithologies, geomorphic settings etc. There are no reliable multi-decadal measurements of bedload export from mountain basins let alone ones that are close enough to glaciers to be able to make links to glacier recession.
This paper uses a unique dataset based upon the high frequency (multiple times per week/year) flushing of small hydropower installations to reconstruct decadal-scale bedload export from 20 Alpine glacierized catchments in western Switzerland over the past 50 years. These catchments are heterogeneous in terms of geomorphology, geographic characteristics and glacierized area. Built to divert water from river channels for hydroelectric power generation, the hydropower installations are equipped with sediment traps designed to separate sediments from the water before it is routed to turbines or stored in artificial reservoirs. Once a threshold volume is reached, these traps must be emptied from sediments (an operation known as flushing). By combining information on the annual frequency of flushing events with analysis of the flushing operation and the volumes of sediments released, it is possible to reconstruct the evolution of bedload over recent decades.
Results show an upward trend in sediment transport since the late 1980s for most of the catchments analysed, coinciding with the onset of rapid Alpine warming in the mid 1980s. Bedload transport slowed in the 1990s, seemingly associated with a series of years with reduced up-glacier snowline recession, before accelerating again in the early 2000s. There is some evidence of peak sediment export in the 2010s. An observed relationship exists between glacierized area and sediment export: bedload export in catchments with a glacier cover lower than about 1 km2 invariably appear to have gone through a shift from ice-erosion driven to summer-rainfall driven. However, some glaciers show anomalous behaviour, including emerging evidence of the direct effects and legacy of glacial overdeepenings. This can lead to site-specific, geomorphologically-influenced responses of bedload transport on top of the underlying regional-scale trend of climate warming.
How to cite: Gianini, M., Repnik, L., Argentin, A.-L., Pitscheider, F., Bizzi, S., Comiti, F., and Lane, S.: Human-induced climate warming, “peak water” and “peak sediment” in deglaciating Alpine catchments, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-10066, https://doi.org/10.5194/egusphere-egu26-10066, 2026.
The Brahmani River Basin (BRB), located within the Eastern Ghats and encompassing the Chhotanagpur Granite Gneissic Complex and Singhbhum Craton, represents a morphodynamically active system governed by structural, climatic, and anthropogenic interactions. Spanning approximately 40,000 km², the basin displays pronounced physiographic contrasts, transitioning from steep, dissected highlands in its upper reaches to low-gradient alluvial and deltaic plains along the coastal outlet. Quantitative morpho-tectonic analyses using stream-length gradient (SL), normalized channel steepness (Ksn), and χ-integral metrics revealed systematic variations that indicate active drainage rearrangement and ongoing surface uplift.
Higher χ values and steep Ksn indices within the Lawa, Sankh, South Koel, and Karo sub-basins signify tectonically rejuvenated terrains, whereas low values in the lower Brahmani and Tikera systems denote mature, equilibrium conditions. Notably, abrupt increases in Ksn and SL values immediately downstream of Rengali Dam correspond to both reservoir-induced base-level perturbations and reactivation of structural lineaments, including the Kerajang Shear Zone (550–500 Ma) and the Barakot Fault (950–700 Ma). Spatial χ-gradient reversals identify active drainage divide migration, toward the northwest in the Lawa Basin, northeast in the Sankh and Koel systems, and southeast within the South Karo Basin. The alignment of these divide shifts with major fault systems (e.g., NOBF, Akul Fault, Malaygiri Lineament) implies tectonic rejuvenation possibly linked to Himalayan compressional stresses. A total of 154 knickpoints were identified, 60% of which are structurally controlled, with 34% lithologically derived, underscoring the interplay between tectonic inheritance and rock erodibility. Basin-wide Ksn values (1.54–29.40 m⁰·⁹) confirm heterogeneity in uplift and incision dynamics, supporting relatively active tectono-geomorphic evolution across the region.
Hydromorphic assessment using the Revised Universal Soil Loss Equation (RUSLE) indicated intensified anthropogenic erosion. The mean soil erosion rate between 2015 and 2025 was estimated at 12.6 t ha⁻¹ yr⁻¹, with nearly 9% of the basin undergoing severe erosion (>40 t ha⁻¹ yr⁻¹), concentrated in structurally deformed uplands. Stable alluvial plains recorded significantly lower values (~3.2 t ha⁻¹ yr⁻¹). Under future climatic scenarios (RCP8.5), basin-wide soil erosion is projected to increase by approximately 16% between 2050 and 2070, driven by enhanced monsoonal erosivity and rapid cropland and built-up expansion.
Sediment connectivity analysis further revealed spatial variability in sediment transfer efficiency. The IC_channel index ranged from –6.97 to 3.03, highlighting steep, narrow valleys in the plateau margins as transport-active corridors. Conversely, low IC_outlet values (–8.59 to 4.25) along low-slope alluvial belts indicate sediment storage zones, reinforced by reservoir-induced trapping. A clear scale-dependency in the Sediment Delivery Ratio (SDR) was observed, with smaller sub-watersheds (>0.40) showing higher transfer efficiency compared to larger basins. Among the 280 delineated sub-watersheds, SW46 recorded the maximum SDR (≈0.47), whereas SW261 represented the lowest (~0.23).
Collectively, these results establish that sediment transfer within the Brahmani Basin is dominantly controlled by tectonic reactivation, topography, and anthropogenic pressures. Steep, structurally active uplands act as primary sediment sources, while downstream plains function as depositional sinks regulated by geomorphic and human interventions, providing a comprehensive understanding of erosion–connectivity coupling under evolving climatic and structural regimes.
How to cite: Roy, A., Pravin, P. P., and Sen, A.: Tectonic, Litho-Structural, and Anthropogenic Controls on River Profile Characteristics in the Brahmani River Basin, Eastern India, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-395, https://doi.org/10.5194/egusphere-egu26-395, 2026.
Throughout the Quaternary, glacial lake outburst megafloods (discharge >106 m3/s) sourced from the Tibetan Plateau played an important role in shaping the mountainous landscape of the Yarlung-Siang River (YSR). While these floods are famous for their landscape disruptions and intense erosional scars, the depositional legacy of megafloods may be equally important for landscape evolution—creating and maintaining the low-relief terraces that today support human settlement and agriculture in this otherwise rugged terrain.
Along the main flood pathway, megaflood-transported boulders can generate localized low-relief zones. We observe >100 boulder bars in the YSR that have boulders too large to be moved by annual, or even historic flows. Where boulder bars are deposited in close proximity during a flood, they locally decrease erosion rates, causing a decrease in slope between consecutive bars over a few thousand years. These low slope reaches of the YSR likely experience enhanced deposition during monsoon flooding, potentially forming low-relief terraces adjacent to the YSR as the channel incises and abandons these surfaces. Regardless of genesis, any low-relief surface that is inundated during a megaflood (whether formed by megaflood boulders or through other unrelated processes like landsliding) will experience low bed shear stresses during the flood, causing these surfaces to act as sites of preferential megaflood deposition. Hydraulic modeling demonstrates that once these surfaces exist, subsequent megafloods can easily deposit on them, reinforcing their low-relief character through repeated cycles of inundation and deposition. Along the YSR, there are often co-occurrences of towns/agricultural fields, large boulders, and slackwater deposits.
Megafloods also generate substantial deposition far beyond the mainstem flood pathway through backflooding of tributaries. Hydraulic modeling shows that backwater inundation likely extended ~60 km up the anomalously low-relief Siyom River from its confluence with the main flood pathway along the YSR. In the Siyom River valley, aggradational terraces preserve distinct sedimentary facies including laminated sands, clays, and peat consistent with slackwater deposition from temporarily impounded waters. Radiocarbon ages from these deposits (10 ka) overlap temporally with inferred occurrences of Tibetan paleolakes, while detrital zircon geochronology reveals that young Tibetan zircons are present in these slackwater deposits—consistent with a megaflood source for these deposits. The low-relief landscape of the Siyom River valley will naturally become a depo-center if inundated by a megaflood, during which low bed shear stresses are produced due to complex backflooding flow dynamics. This deposition will further reinforce the low-relief character of this valley—a valley that is now home to the town of Aalo(ng), the fourth most populous town in the state of Arunachal Pradesh as of 2011.
Together, these processes demonstrate how catastrophic floods can paradoxically generate geomorphic stability in these low-relief surfaces. While megafloods represent extreme disruptive events, their depositional products create zones of sustained low-relief landscapes that persist for tens of thousands of years, the coincidence of modeled low shear stress zones, depositional facies, and modern agricultural lands reveals this legacy: catastrophic surface processes that disrupt the broader landscape while simultaneously creating resilient, habitable spaces within it.
How to cite: Morey, S., Huntington, K., Lang, K., and Shobe, C.: Of Boulders and Backflow: how catastrophic megafloods create temporally sustained low-relief surfaces in eastern Himalayan river valleys , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-21285, https://doi.org/10.5194/egusphere-egu26-21285, 2026.
Mountain rivers have always been of crucial importance to human societies, as they serve as a source of drinking water, irrigation, and energy supply, but also pose dangers in the form of flooding. In prehistoric times, water in fluid and frozen form was the main natural processes shaping the landscape, and human impact were mostly minimal. Early agricultural societies began modifying rivers through irrigation channels, terracing, livestock grazing and last but not least dam constructions, which mostly changed river morphology and sediment load only at the local level. Nowadays, a large proportion of the rivers worldwide have been altered by hydraulic engineering projectsat a global level. In the Anthropocene Discourse, dams are considered one of the important indicators of the anthropogenic transformation of river landscapes.
Against this background, the present study investigates when and in what ways humans began to alter watercourses and flood regimes through water infrastructure, in particular by the constructions of dams and relataed infrastructure in mountain regions using the Harz Mountains as a case study. As highest upland region in Northern Germany, it is naturally prone to flooding, especially the more rugged regions in the W-Harz. Since historical times, floods have altered the landscape and led to extensive destructions for settlements in the mountains and their forelands. The high extent of damage caused by flooding was one of the reasons for the construction of six large dams in the W-Harz during the 20th century. They have drastically reduced the occurrence of floods, thereby altering the natural flow dynamics of the rivers.
However, already in historical times, rivers were modified by the water management for mining activities and timber rafting. In the Early Modern Period, the Harz Mountains represented one of Europe's largest mining regions for the extraction of ores such as silver, copper, and lead. To supply the mines with energy, an extensive water management system with artificial ponds, ditches and underground waterways was constructed between the 16th and 19th centuries, the largest energy supply system for mining of its time, and since 2010, part of the UNESCO World Heritage in the Harz. The study provides an overview of anthropogenic changes or river systems and flooding events, examining their spatial and temporal distribution from a historical perspective with a special emphasis on the former mining district of St. Andreasberg in the catchment areas of the rivers Oder and Sieber. The study is based on field work carried out since 2016 in the Harz Mountains, the analysis of historical archives (reports, maps, photographs) and digital elevation models. In the context of the predicted increase in extreme hydrological events in Germany, knowledge of the historical development of rivers and the extent of anthropogenic influence is crucial for landscape management, nature conservation, risk management and the preservation of historical monuments in mountain regions.
How to cite: Iturrizaga, L.: Hybrid River Landscapes in Mountain Regions: Anthropogenic Changes of Rivers and Flood Events in the W-Harz (Germany) from a long-term perspective, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-11325, https://doi.org/10.5194/egusphere-egu26-11325, 2026.
Abstract: Heterogeneity of ground substrates is a key controlling factor for vegetation differentiation in mountainous regions. However, the cascading regulatory mechanism involving lithological differences, substrate structure, water retention, and vegetation response remains unclear. This study focuses on three typical ground substrate areas in the Yanshan Mountains of northern China—granite, gneiss, and dolomite regions—located within the ecological barrier zone of the Beijing–Tianjin–Hebei region. By integrating multi‑source data from field trenching, shallow well excavation, in‑situ electrical detection, vegetation quadrat surveys, and remote sensing inversion, the regulatory mechanism of lithological differences on vegetation coverage was revealed. The results indicate that: (1) The development of bedrock fractures and the appropriate grain size composition of the substrate directly affect the water‑holding capacity of the ground substrate, influencing root distribution and plant water‑use strategies, thereby controlling the spatial distribution characteristics of vegetation. (2) Bedrock fracture density shows a significant positive correlation with vegetation coverage (r2= 0.79), with the order being granite > gneiss > dolomite. Ground substrate moisture content is positively correlated with the proportion of silt‑clay particles (<0.063 mm) (r=0.82) and negatively correlated with the proportion of sand particles (≥0.063 mm) (r=−0.76). Lithological differences result in a water‑holding capacity order of dolomite > gneiss > granite. (3) The thickness of the bedrock weathering layer (granite > gneiss > dolomite) and fracture density jointly control vegetation root distribution, providing a scientific basis for differentiated vegetation restoration strategies based on lithological characteristics in mountainous regions of northern China.
Keywords: lithological differences; vegetation type; vegetation coverage; constraining mechanism; Yanshan Mountain
Funding: This study was supported by the National Natural Science Foundation of China (Grant No. U2344227)
How to cite: Yin, Z. and Sun, Z.: Constraining Mechanism of Lithological Differences in Ground Substrates on Vegetation Coverage in the Yanshan Mountain of Northern China, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-2370, https://doi.org/10.5194/egusphere-egu26-2370, 2026.
Cold scree slopes are fascinating geomorphological features governed by a complex reversible internal ventilation system known as the chimney effect, which leads to a pedoclimate that is wetter and around 10 to 15°C colder than surrounding environments. They typically occur in montane and subalpine belts in the Alps (900-2,000 m a.s.l.) and are found across most temperate mountains worldwide. The constantly overcooled scree area harbours small azonal environments (a few hectares at most) with sparse dwarf trees, surrounded by the usual fir, beech or spruce forests. These conditions engender an open understorey, thereby fostering the establishment of boreo-arctic communities dominated by ericaceous shrubs, terricolous lichens, and bryophytes. The combination of the high primary productivity of bryophytes, which is due to the availability of light and wetness, and the cold pedoclimate, which inhibits the activity of soil fauna, results in atypical soils with remarkable accumulations of raw organic matter. Overall, the isolation provided by the thick layer of soil organic matter and bryophytes strengthens the ventilation system.
Thanks to their stable cold micro-pedoclimate, these unique ecosystems are considered as microrefugia: their boreo-arctic islands harbour isolated cold-adapted species surrounded by mountain forests since the end of the Pleistocene. Yet the cold scree slopes that we know today are under threat from climate change, as the chimney effect requires sufficiently cold winters in order to function. However, new ones are likely to occur at higher altitudes in the future, where similar ventilation systems are appearing on today's unvegetated scree slopes in the alpine belt. Identifying where such geomorphological processes could sustain future microrefugia is therefore critical for the conservation of cold-adapted species in warming temperate mountains.
How to cite: Meynier, S.: How geomorphology shapes unique alpine microrefugia: Plants and soils in cold scree slopes, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-6879, https://doi.org/10.5194/egusphere-egu26-6879, 2026.
Braided rivers represent extraordinary wetland ecosystems due to their high disturbance regimes. Their riparian vegetation needs to be adapted to these harsh conditions. At the same time, braided river systems are sensitive to changes in the underlying environmental factors. Additionally, their open gravel and sand banks represent germination sites for invasive alien plant species. There is a risk that invasive species can spread over large areas and thus alter river reaches, even leading to morphological changes in the entire river system.
The aim of this study was to identify similarities and differences in the key functional traits and strategies of invasive alien plants compared to the dominant native plant species in braided rivers around the world. The analysis of what makes invasive species more successful than the native species was carried out in seven globally distributed mountain regions with braided rivers, including parts of the European Alps, the mediterranean Vjosa river system, Iceland, Alaska, Patagonia, Central Asia, and New Zealand. Studied river system cover different climate zones, with varying degrees of human influence.
We used a plot design (10m by 10m) covering all occurring biogeomorphic succession phases (Corenblit et al. 2007) in the investigated river reaches. In each plot, we recorded general information on the habitat conditions and vegetation characteristics. We combined the field data with response and effect trait data from the TRY trait database (Kattge et al. 2020). The traits of the dominant native and invasive alien plant species were compared using a PCA analysis to reveal differences in trait combinations that can explain the success of invasive species.
First findings indicate that successfully invading alien species enter the braided river systems in the pioneer succession phase and comprise traits for dealing with the high hydromorphodynamic disturbances, for example a short lifespan. They have rather smaller specific leaf area and plant height. By decreasing the disturbance impact through dense vegetation cover and trapping of fine sediment they push their growing areas to the following biogeomorphic succession phase. Here, especially invasive ecosystem engineer species improve their own growing conditions and may create dense vegetation covers in the formerly open active channel.
Across our study areas, a wide range of the magnitude of plant invasion was visible: While in the Alaskan rivers with extreme arctic to boreal climate and low human impact no invasive alien plants occured, the braided rivers in the intensively agriculturally used Canterbury region on New Zealand's South Island were highly invaded. Here, many formerly sparsely vegetated active channels were densely covered with alien species and the later succession phases prevailed.
References
Corenblit, D., Tabacchi, E., Steiger, J., & Gurnell, A. M. (2007). Reciprocal interactions and adjustments between fluvial landforms and vegetation dynamics in river corridors: a review of complementary approaches. Earth-Science Reviews, 84(1-2): 56-86.
Kattge, J., Bönisch, G., Díaz, S., Lavorel, S., Prentice, I. C., Leadley, P., Tautenhahn, S., & Werner, G., et al. (2020). TRY plant trait database - enhanced coverage and open access. Global Change Biology, 26(1): 119-188. doi:10.1111/gcb.14904
How to cite: Becker, I., Egger, G., and Eichel, J.: Which strategies enable alien plant species to invade braided river systems? , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-11344, https://doi.org/10.5194/egusphere-egu26-11344, 2026.
Riparian and channel vegetation play a crucial role in fluvial sediment dynamics and riverbank stability. We investigated vegetation-sediment interactions along the Saja and Besaya rivers (northern Spain) through two complementary analyses combining LiDAR and multispectral imagery.
First, we assessed the influence of riparian vegetation on bank stability by delineating 100-m longitudinal reaches classified as erosive or stable. LiDAR data were used to quantify total woody vegetation cover, tree cover, and the mean vegetation height (as a proxy for maturity) across riparian strips of varying widths (10, 20, 30, and 50 m). Logistic regression models showed that riparian vegetation significantly reduced the probability of bank erosion, with minimal variability among predictors. The strength of these vegetation metrics was highest when calculated at a 10-m stripe, and it broadly decreased at 50 m, which suggests that vegetation adjacent to the bank was sufficient to mitigate erosion risk. These findings support the conservation and restoration of riparian woody vegetation as a potential nature-based solution for bank erosion prevention in sensitive areas.
Second, we examined in-channel sediment balances at 10x10 m pixels using multitemporal LiDAR (2018-2023) and Sentinel-2 imagery. Sediment balance was derived from LiDAR elevation changes and expressed as continuous (m3) and binary (erosion vs. non-erosion). We analyzed Sentinel-2 series to derive pixel history (yearly frequency and persistence of in-channel vegetation) and harmonic metrics (decomposing the NDVI series). Random Forest models indicated that pixels with decreasing vegetation persistence and negative NDVI trends were more likely to experience erosion. While predicting the magnitude of the balance was challenging, classification into erosion vs. stability achieved better performance. These results highlight the capabilities of multispectral image series to assess erosion and sediment processes in fluvial ecosystems and complement LiDAR data in river monitoring.
Overall, our study shows that riparian vegetation strongly influences bank stability and that vegetation dynamics within the channel are linked to sediment deposition and erosion. By integrating high-resolution LiDAR and multispectral imagery, we provide evidence that maintaining riparian vegetation can serve as an effective nature-based solution for reducing bank erosion processes. Furthermore, our approach underscores the value of combining remote sensing techniques to improve the understanding and management of sediment processes in highly dynamic river systems.
How to cite: Fernández-Menéndez, Á., Concostrina-Zubiri, L., Cecchetto, M., Taffetani, E., Bizzi, S., and Barquín, J.: Vegetation-sediment interactions and bank stability in Atlantic rivers: Linking multispectral approaches and LiDAR data, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-16612, https://doi.org/10.5194/egusphere-egu26-16612, 2026.
Significant progress has been made in the field of fluvial biogeomorphology in the last two decades regarding how vegetation and fluvial landforms co-adjust to shape rivers within different rivers and disturbance regimes. However, the understanding of biogeomorphological behaviors that emerged is largely built on studies made in temperate regions with a focus on flood regime. While over 20% of the worldwide continental surface lay in cold climate, rivers in these regions have been largely underrepresented in biogeomorphology and are worth exploring considering the presence of fluvial ice dynamics. These rivers are subjected to an array of ice forms and processes that are known to affect flow structure, sediment dynamics, fluvial landforms and vegetation through ice-related flood and scour disturbances. Combining previous research results and literature reviews, this presentation aims to integrate fluvial ice dynamics into existing biogeomorphological concepts to generate new hypotheses about river behavior in cold climate. We first present and describe known ice forms and processes and their effects on riverscapes that may have significant implications for river-vegetation co-adjustment mechanisms. Then, we discuss how fluvial ice dynamics may modulate the expression and structure of biogeomorphological interactions. Based on study cases, we emphasize from evidence-based interpretation that ice dynamics do have a significant role to play in the trajectories and evolution of cold rivers. We use core frameworks from the field of biogeomorphology to trace these modulations across scales, from individual plant traits to landscape spatial organization. Reflections and hypotheses that are presented through out this discussion reveal the wide gradient of control ice dynamics can exert on different fluvial contexts and highlight key research gaps and avenues essential to increase our understanding. It is proposed that efforts must be put into long-term monitoring, comparative studies and numerical modeling to test different hypothesis and frame the place of ice dynamics within biogeomorphological frameworks. Not only these suggestions are of particular interest for theoretical advancements in understanding cold rivers behavior, but they would also provide invaluable insights for better prediction and management in a context of climate change.
How to cite: Prugne, M., Buffin-Bélanger, T., Boivin, M., and Corenblit, D.: The biogeomorphology of cold rivers: exploring the effects of ice dynamics from plants traits to landscapes, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-5628, https://doi.org/10.5194/egusphere-egu26-5628, 2026.
Beavers modify rivers and floodplains by building dams, increasing sediment and carbon storage, and creating habitat for biota. In the Rocky Mountain region, USA, beavers are being reintroduced for river restoration, with goals that include promoting sediment storage in incising reaches and decreasing downstream fluxes of sediment and associated constituents. Human-built dams that impound rivers and create reservoirs also store sediment within river corridors, but they lack the significant ecosystem benefits associated with beaver activity. Here, we ask: what is the relative magnitude of potential beaver-induced sediment storage compared to sediment storage in human-built reservoirs? We modeled beaver dam capacities in river corridors with the beaver restoration assessment tool (BRAT), which leverages landcover and topographic geospatial data to determine the maximum potential density of beaver dams on the river network. Based on potential dam density, we estimated potential beaver-related sediment storage across the region using field-derived statistical relationships between pond characteristics and sediment volumes. We used national sedimentation models trained on repeat reservoir survey data to estimate reservoir sediment storage. These sedimentation models are built upon ResNet, a dammed reservoir network that links US dams with the US National Hydrography Dataset. We found that if beaver were at 100% capacity, the magnitude of potential beaver-related sediment storage in the Rocky Mountain region would be ~2.8 km3. This is similar to sediment storage in human-built, dammed reservoirs in the region modeled for the years 2025 (~2.2 km3) and 2050 (~2.8 km3). For some drainage basins in the region, potential beaver-related sediment storage exceeds sediment storage in human-built reservoirs. To date, most studies of beaver-induced sediment storage in river corridors have occurred over relatively small spatial extents (individual ponds, reaches, and small watersheds). However, estimating potential sediment storage due to beaver over larger spatial extents is important for informing management of landscape-scale sediment storage, especially if a goal is to reduce downstream sediment loading to reservoirs. Our results allow for assessing the relative impact of beaver dams versus human-built dams on distributed sediment storage at the watershed and regional scales.
How to cite: Lininger, K., Scamardo, J., Shobe, C., Sholtes, J., Hurst, A., Eckland, A., and Foster, M.: Comparing Potential Beaver-related Sediment Storage to Human-built Reservoir Sediment Storage in the Rocky Mountain Region, USA, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-11161, https://doi.org/10.5194/egusphere-egu26-11161, 2026.
River corridors, i.e. channels and the adjacent floodplains, are hotspots of biodiversity and provide manifold ecosystem services. Their landscapes emerge from strong interactions between hydromorphology and vegetation. These biogeomorphic feedbacks not only shape planform development but also control riverine ecosystem functioning as underlying foundation of biodiversity and ecosystem service provision. Understanding these hydromorphology-vegetation interactions is central to the growing sub-discipline of biogeomorphology. Regular disturbances such as floods and droughts reorganize channels, generating pronounced spatiotemporal variability in hydrology and landform heterogeneity that promotes the recruitment of biogeomorphic keystone species such as Salix, Populus or Hippophae. Following establishment, these species can cross engineering thresholds, modify habitat conditions, and shape successional trajectories. The fluvial biogeomorphic succession model is a central framework for conceptualizing and studying these hydromorphology-vegetation feedbacks. Today, many rivers exhibit reduced geomorphic dynamics due to anthropogenic modifications and, simultaneously, face hydrologic change driven by climate change.
In our contribution, we apply the biogeomorphic succession model to the Naryn River in Kyrgyzstan, a still free flowing river on a length of more than 600 km. However, dams are under construction and expected to strongly modify hydromorphological and ecological dynamics in future. We found that within-channel hydrogeomorphic processes and disturbances exert a substantial – yet often overlooked – control on floodplain habitat development and their ability to provide ecosystem services. Even small changes amplified by biogeomorphic feedbacks can trigger the crossing of tipping points and shift ecosystem trajectories at reach scale. A fundamental mechanism is the determination of habitat availability for plant communities by the interplay of hydrologic connectivity and biogeomorphic feedbacks. Landforms arising from these feedbacks and associated with shallow groundwater are particularly important, acting as key habitat patches and biodiversity reservoirs along river corridors. Beyond the widespread anthropogenic influence on river corridors, climate change may shift discharge regimes and other boundary conditions, subtly reorganizing vegetation–hydromorphology couplings and potentially driving changes in river typology and riparian ecosystems. As biogeomorphic feedbacks and their response to anthropogenic river modifications and climate change are a key driver of riverine ecosystem functioning, it is crucial to further extend our existing scientific understanding and transform it into science-based, integrated river and floodplain management.
How to cite: Lauermann, M. and Betz, F.: Linking biogeomorphic feedbacks and hydrologic connectivity as key drivers of riverine ecosystem functioning, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-13991, https://doi.org/10.5194/egusphere-egu26-13991, 2026.
The world is facing many challenges, most of them associated with nature. And yet, much of the focus of nature within these challenges has been on biodiversity. In contrast, geodiversity remains underutilised by policymakers and still relatively unknown to the general public. Moreover, it is being exposed to various risk and threats, e.g., urban development, changes of land-use, irresponsible and intensive quarrying or mining, overexploitation of geodiversity sites by visitors, social pressure regarding the use of geodiversity, climatic changes or emphasizing the protection and management of living nature at the expense of geodiversity. Recognising the importance of geodiversity in many of the questions facing society, we identify four Geodiversity Challenges that require attention:
- Recognition: Geodiversity needs to become a publicly recognised concept, on a par with biodiversity. If successful, the public would increasingly identify geodiversity and its components as important parts of nature.
- Understanding: Geodiversity should be represented in school curricula, and recognized and effectively interpreted at heritage sites, protected areas and tourist trails. This will also increase the number of young people attracted to choose geoscience for their career and higher education as well as effectively contribute to the awareness of geodiversity among the general public.
- Conservation: Similarly to biodiversity sites, sites containing significant geodiversity features need protection and management. Besides this, every geoconservation effort should be accompanied by consideration of possible risks and threats and effective proposals for the future management. This requires the inclusion of geodiversity in policy decision making, e.g., via monitoring Essential Geodiversity Variables or developing the concept of geosystem services and disservices. If effective, this may contribute to a more effective engagement and action of policymakers, and to the respect, acceptation and support of geoconservation by general public.
- Utilisation: Geological resources are essential to our way of life, especially as technology becomes more dominant as society works towards a green economy. These resources need to be utilised in a sustainable way. Essential minerals for the green economy should be extracted and processed in a sustainable and ethical manner in accordance with SDGs.
Science has increasingly become an interdisciplinary enterprise, especially as we seek to confront more difficult challenges. We should also recognise that the aspects of our planet are interconnected, and that solutions to the threats nature faces will not be as strong as we wish if geodiversity is forgotten by scientists and policymakers, and not acknowledged by the general public. The time has come for geodiversity to take its place alongside biodiversity as a recognised and useful part of nature.
References:
Matthews, J., Kubalíková, L., Štrba, L., & Tukiainen, H. (2024). Geodiversity challenges for a sustainable future. Nature Geosciences, 17, 948. https://doi.org/10.1038/s41561-024-01551-w
Justice, S., Crofts, R., Gordon. J.E., & Gray, M. (2025). The meaning of Nature: Clarification for strengthened protection and management. IUCN WCPA Issues Paper Series No. 5, Gland, Switzerland: IUCN. Available at: https://iucn.org/sites/default/files/2025-01/meaning-of-nature_pdf-final.pdf
This work was supported by the Czech Academy of Sciences under the project Strategy AV 21 - Dynamic Planet Earth and by the Slovak Research and Development Agency under the project no. APVV-24-0554.
How to cite: Kubalíková, L., Matthews, J. J., Štrba, Ľ., and Tukiainen, H.: Can We Save The Planet Without Saving The Planet? Geodiversity challenges for a sustainable future, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-3351, https://doi.org/10.5194/egusphere-egu26-3351, 2026.
The conservation of geosites is a central aspect of geoconservation, as they represent
critical and unique records of Earth’s history, past biodiversity and processes. Effective
conservation requires systematic management and continuous monitoring to mitigate
both natural and human-induced threats. Despite the increasing recognition of geological
heritage, standardized approaches for evaluating and maintaining the conservation
status of geosites remain limited. This study proposes a structured framework for
monitoring and managing geosites that is adaptable across diverse contexts. The
methodology integrates a multi-phase process, beginning with identification of potential
threats, and selection of relevant indicators that reflect the quality and conservation
status of each site. Subsequent stages include defining measurable parameters,
establishing minimum acceptable standards, and implementing monitoring techniques
that capture temporal changes and degradation patterns. Both direct and indirect
methods are considered to detect impacts arising from natural processes and
anthropogenic activities. We also proposed the possible incorporation of interpretive and
promotional strategies to support public awareness and the sustainable use of geological
resources. Preliminary application of this framework allows for systematic evaluation of
site conditions and enhances the capacity of managers to make evidence-based
decisions. By linking indicators to conservation priorities, the framework enables the
identification of critical areas requiring intervention, facilitates the establishment of short-
, medium-, and long-term management goals, and supports adaptive strategies that
respond to evolving threats. Additionally, the integration of ecosystem service
considerations and educational tools strengthens the societal relevance of
geoconservation initiatives. The expected outcomes include improved understanding of
the dynamics affecting geosites, enhanced capacity to detect degradation early, and a
standardized approach that promotes consistent monitoring across sites. Ultimately, this
model provides a robust and flexible tool for advancing geoconservation strategies,
fostering sustainable management, and safeguarding geological heritage for future
generations. By formalizing monitoring procedures and linking them to conservation
objectives, the study contributes to the establishment of clear cause–effect relationships,
effective communication of geosite value, and the long-term resilience of geological
features within protected areas.
This project was funded by Portuguese Foundation for Science and Technology (FCT)
reference number SFRH/BD/146016/2019
How to cite: Siqueira, T., Pereira, P., and Vegas, J.: Geosite monitoring: a framework for practical application, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-3890, https://doi.org/10.5194/egusphere-egu26-3890, 2026.
Teide National Park (TNP), declared in 1954, is one of Spain’s 16 national parks. It covers 189.9 km² and ranges from 1,600 to 3,718 m a.s.l. Its volcanic landscape results from eruptions of mafic to felsic magmas, with eruptive styles from Hawaiian to sub‑Plinian. The park hosts a wide variety of volcanic geoforms—such as a large caldera of debated origin, the active stratovolcanoes Teide and Pico Viejo, numerous domes, monogenetic basaltic cones, hornitos, dikes, and diverse lava flows (ʻAʻā, pāhoehoe, blocky, and obsidian). Lava tubes, lava channels, and other minor morphologies are also present, along with non-volcanic features produced by torrential processes, hillslope dynamics, landslides, subsidence, glacial and periglacial activity, aeolian processes, and historical quarrying. In addition to its natural heritage, TNP preserves important cultural elements, including archaeological remains and traditional agricultural and pastoral uses, as well as current activities such as beekeeping.
TNP is the most visited protected natural area in Spain, with an annual average exceeding 3 million visitors; in 2025, visitation surpassed 5 million. The aim of this study is to relate the volcanic geoheritage to TNP’s use zoning as a first step toward identifying threats derived from visitor pressure. For this purpose, the geomorphosites defined in TNP’s four geomorphological units—Teide–Pico Viejo, Las Cañadas wall, Las Cañadas courtyard, and the monogenetic volcanic field—were analysed according to their zoning categories (reserve, restricted, and moderate use).
A total of 23 geomorphosites were identified: 8 in Teide–Pico Viejo, 4 in Las Cañadas wall, 6 in the courtyard, and 5 in the volcanic field. Of these, 5 fall within reserve zones (Pico Viejo crater, Fortaleza, Diego Hernández Cañada, Las Cañadas taluses, and the Fasnia historical eruption), where no recreational use is allowed; therefore, no conflicts exist. Thirteen geomorphosites lie within restricted use zones (including Teide, Chahorra, Guajara, Los Gemelos, Montaña Blanca, Montaña Rajada, the Roques Blancos and Pico Cabras domes, Montaña Negra, obsidian lavas, and Corrales volcano). Here, visitor impact is limited because access is confined to established trails; however, some sites (notably Samara and Guajara) receive visitor levels that may threaten their integrity.
The greatest pressures occur in the five geomorphosites located in moderate-use areas (Mostaza cone, Roques de García, Llano de Ucanca, the eastern volcanic field, and Guamasa cone), where pedestrian access is unrestricted and regulated vehicle traffic is still permitted. Among these, mass visitation has the most significant impacts at Roques de García, and to a lesser extent at Llano de Ucanca and the viewpoints of the eastern volcanic field.
Mass visitation has been a concern for managers and scientists for years. At the end of 2025, a new management plan was approved that restricts private vehicle access and prioritizes sustainable mobility. However, it does not directly address the core issue: the concentration of visitors at specific sites and times. Therefore, scientific studies focused on the geoconservation of TNP’s volcanic geoheritage are essential, as they can serve as key reference documents for the management of both natural and cultural heritage.
How to cite: Dóniz-Paéz, J., Becerra-Ramírez, R., Rodríguez, O., and Pérez, N. M.: Identifying threats of the volcanic geoheritage in the Teide National Park (Tenerife, Spain) based on visitor’s use, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-13812, https://doi.org/10.5194/egusphere-egu26-13812, 2026.
The Dolomites (NE Italy) are among the most famous and popular mountains in Europe and the world. Due to their outstanding aesthetic value and striking geological and geomorphological features, the Dolomites have been recognised as a UNESCO World Heritage Site.
However, like other high mountain areas, the Dolomites are characterized by intense geomorphological dynamics, which are partly exacerbated by climate change and compounded by growing anthropogenic pressure. These dynamics lead to the constant evolution of the landscape and its landforms. In turn, this evolution could constitute a risk factor for the degradation of the area's geological heritage. Therefore, in order to conserve and manage the geological and geomorphological attributes that led to the UNESCO recognition, it’s important to assess their degradation risk and, if necessary, monitor their evolution over time.
This research focuses on developing and testing a methodological framework to assess the risk of degradation and identify geoindicators for geosite monitoring within the Dolomites World Heritage Site. The proposed workflow consists of the following main phases: i) geomorphological field surveys, aimed at characterising the sites and identifying the geomorphological, biological or anthropogenic processes currently active in the area; ii) qualitative assessment of the risk of degradation using the criteria of fragility, natural vulnerability, anthropogenic vulnerability and sensitivity to climate change (sensu Garcia-Ortiz et al., 2014); iii) definition of desirable conditions of conservation; iv) identification of site-specific indicators for monitoring.
The methodology has been tested on several sample sites, for which the preliminary results are given. High fragility and natural vulnerability were mainly associated with small, finite sites (e.g. paleontological sites, earth pyramids); in some sites there are also incipient effects of greening. Anthropogenic vulnerability was assessed as low to medium for all the analysed sites – however, some large, complex sites include geological features that are more vulnerable to human impact than the site as a whole. The sensitivity to climate change of the analysed sites is low to medium. In general, the conditions of conservation observed in the field correspond to the desirable conditions.
The proposed methodology provides an operational, evidence-based protocol for integrating geomorphological analysis into geoheritage monitoring and geoconservation, and offers a transferable framework for other World Heritage properties, Geoparks and protected areas.
How to cite: Ferrando, A., Carton, A., Coratza, P., Soldati, M., and Vandelli, V.: Degradation risk assessment and geomorphological mapping for geoconservation at the Dolomites UNESCO World Heritage Site (Italy), EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-20474, https://doi.org/10.5194/egusphere-egu26-20474, 2026.
High-mountain regions attract increasing numbers of visitors and provide ecosystem services related to recreation and spiritual activities. At the same time, these environments are geomorphologically sensitive and can be readily degraded when tourism and recreational use are insufficiently managed. Such degradation may reduce recreational potential and increase risks to visitors and local communities.
This study documents and maps landscape degradation associated with tourism and tour-operator activities in high-altitude terrain (>4000 m a.s.l.) in the Miyar Valley, Himachal Pradesh, India. In recent years, the area has experienced a rapid increase in visitor numbers, including large organised groups (>20 individuals), resulting in pronounced impacts on the physical landscape.
Field investigations were carried out during the 2025 field season. Geomorphological mapping combined systematic field-based surveys with the interpretation of high-resolution satellite imagery (WorldView and Pleiades). Dominant morphogenetic processes were identified and characterised using ground observations, photographic documentation, and remote-sensing data.
Five dominant geomorphological processes contributing to landscape degradation were identified: (1) vegetation trampling by hikers and pack animals, primarily horses; (2) soil erosion on exposed surfaces, leading to rill development and enhanced surface runoff; (3) soil compaction, resulting in surface hardening that promotes accelerated runoff and increased downslope water erosion; (4) freeze–thaw cycles, which weaken soil and regolith structure and increase susceptibility to erosion; and (5) dry–wet cycles, which further predispose soils to degradation.
These processes produce characteristic trail-related geomorphological features, including deeply incised trail surfaces, wide unvegetated trail treads indicative of vegetation loss and high erosion potential, water ponding in low-gradient sections leading to muddy conditions and subsequent trail widening due to avoidance behaviour, and litter accumulation. Based on the collected data, a trail classification scheme was developed that incorporates a functional model of trail behaviour under contrasting topographic settings (sloping versus flat terrain).
The results indicate that, in this high-mountain environment, rapid increases in visitor numbers can lead to long-lasting geomorphological changes. Management interventions, particularly focused on trail design and maintenance, are therefore important for limiting environmental degradation, improving visitor safety, and reducing impacts on the surrounding landscape.
The research was funded by the Polish National Science Centre, Poland - Project number 2021/43/B/ST10/00950
How to cite: Tomczyk, A. and Ewertowski, M.: Mapping and characterisation of geomorphological impacts of tourism in a high-mountain environment: a case study from the Miyar Valley, India, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-15289, https://doi.org/10.5194/egusphere-egu26-15289, 2026.
How to cite: Singh, M., Ranga, V., Kumar, A., Mukherjee, J., Shukla, S. S., Singhal, M., Raj, A., Dubey, P., Pani, P., Chauhan, N., Thakur, S., Laskar, A. H., Jain, V., and Tooth, S.: Human-nature interactions in the Chambal Badlands, India: geomorphological perspectives on the dual challenges of land degradation and geoheritage promotion, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-15887, https://doi.org/10.5194/egusphere-egu26-15887, 2026.
Industrialization has reshaped the availability, transport, and storage of fluvial sediments, with direct consequences for long-term geomorphic development and for ecological and socioeconomic conditions. A central feature of this shift is the transition between supply- and transport-limited states, which influences river channel stability, floodplain functioning, and habitat dynamics. Reconstructing such sediment regime changes before the mid-20th century is, however, difficult due to sparse or missing data on river geometry, hydraulics, and sediment characteristics.
We propose a probabilistic modeling framework to infer reach-scale tendencies toward supply- or transport-limited behavior across successive phases of industrialization under tight data constraints. The approach links sub-catchment sediment delivery to a reach-scale sediment mass balance, accounting for sediment supply, transport capacity and possible retention.
Sediment delivery to individual sections is estimated with a RUSLE-SDR scheme, incorporating temporal variability through historical land cover reconstructions and by scaling hydrological and climatic inputs based on instrumental and reconstructed discharge and precipitation data. Channel hydraulics and transport capacity are approximated without explicit bathymetry by assigning a planform channel type to each section for each industrialization phase and linking those types to probabilistic distributions of width, depth and roughness drawn from empirical parameter libraries. The present, well-documented river state is used as geometric and hydraulic reference, while historical states are reconstructed according to their map-derived channel type using process-based translation rules.
Uncertainty from incomplete geometry, historical reconstructions, and parameter variability is propagated through Monte Carlo sampling, yielding distributions of sediment transport capacity, export, and retention rather than individual deterministic values. Resulting reach-scale sediment mass balances are evaluated probabilistically to classify reaches based on their likelihood of aggradation, erosion, or near-equilibrium conditions for each industrialization phase.
By emphasizing relative sediment regime tendencies instead of absolute fluxes, this approach enables a systematic comparison of how different phases of industrialization are reflected in sediment dynamics, channel stability, and disturbance regimes of ecological relevance across different river types.
How to cite: Schmalfuss, L., Schmid, M., and Hauer, C.: Reconstructing Reach-Scale Sediment Regime Shifts Across Successive Stages of Industrialization, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-13016, https://doi.org/10.5194/egusphere-egu26-13016, 2026.
Bedforms exert a fundamental control upon water and sediment transport processes in alluvial systems, including the initiation of flow separation, the generation of shear layers and turbulence, flow resistance, bedload transport and sediment trapping. Dunes are common bedforms in alluvial river channels, having characteristic geometries (height, wavelength and lee-slope angles) and reflect the dominant hydraulic and sedimentological conditions in which they are formed. Yet, alluvial reaches are increasingly impacted by anthropogenic activities - including sand mining – which causes instantaneous changes to riverbed morphology, bedform geometries, and therefore water flow and sediment transport.
Here, we compare the anthropogenic morphological signatures of differing sand extraction methods at two reaches using high-resolution bathymetry surveys. Riverbed morphology was classified into five distinct bedform classes: dunes, scour patches, and three different extraction mechanisms: trawled, suction-mined and crane-mined.
Features associated with crane-mining exhibit the greatest roughness (maximum of 5.3) and mean lee-side angle (x̄ =13.04o, maximum 59o, where x̄ = the sample mean); however, trawled features have the largest average roughness (x̄ = 0.67). Dunes display the greatest mean wavelengths (x̄ 44.5 m), yet all mined bedforms display the greatest mean amplitudes (x̄ = 0.87 m, x̄ = 0.65 m, and x̄ = 0.98 m for crane-mined, suction-mined and trawled, respectively). Each sand mining mechanism causes geometrically distinct bedforms than those formed naturally in equilibrium with prevailing flow and sediment conditions, and therefore will have differing effects on flow conditions in which they occur. In particular, mined features with relatively higher roughness may impart greater flow depths beyond observed water levels and localised flood risk. Our work shows that human activitiy can fundamentally alter flows of water and sediment through river reaches, impacting flood risk.
How to cite: Hackney, C., Runeckles, H., Large, A., Do, N., and Le, H.: Differing sand mining mechanisms generate distinct bedform morphologies, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-18491, https://doi.org/10.5194/egusphere-egu26-18491, 2026.
Rivers are highly dynamic environments shaped by strong interactions between riparian vegetation and geomorphic processes, which are influenced by both climatic drivers and human activities. Understanding the functioning of river–floodplain systems is essential for river management, including flood protection and conservation of riparian zones. Satellite imagery provides an effective tool for analysing river and floodplain dynamics, as it offers high temporal resolution and spatial resolutions adequate for medium to large river systems.
The Drava River is one of the best-preserved large lowland rivers in the wider Pannonian region, largely due to its relatively wide riparian corridor. However, the river has experienced substantial human impacts, including channel straightening and meander cut-offs since the 19th century, as well as the construction of three hydropower plants and their associated reservoirs in the Croatian reaches during the 1970s and 1980s. These interventions have led to reduced sediment load, resulting in channel incision and narrowing. Although the Drava River is now protected as a natural area, detailed studies of vegetation–morphology interactions remain scarce. Existing research is largely based on spatially limited field surveys or historical maps with low temporal resolution.
In this study, we employ Landsat satellite data to investigate long-term vegetation and morphological dynamics within the Drava River channel and floodplain, using cloud-based data processing and statistical modelling. The objectives are to analyse changes in channel planform and vegetation coverage, and to examine phenological patterns of floodplain vegetation in relation to groundwater levels and climatic variables. We hypothesize that altered sediment and hydrological regimes following dam construction promote channel narrowing and vegetation expansion within the channel and floodplain. Additionally, we assess how these changes, together with climate variability, affect floodplain forest phenology along a downstream gradient from hydropower dams. Preliminary results derived from classifications using vegetation and water indices indicate a slight but statistically significant increase in vegetation cover. This trend is consistent with findings from other European rivers and is likely linked to reduced sediment flux and prolonged dry climatic periods. The study aims to provide insights into biogeomorphic processes relevant for river management and restoration of the Drava River floodplain.
This work was supported by the Croatian Science Foundation for the ALCAR project: “Assessment of the Long-term Climatic and Anthropogenic Effects on the Spatio-temporal Vegetated Land Surface Dynamics in Croatia using Earth Observation Data” (Grant No. HRZZ IP-2022-10- 5711).
How to cite: Pavlek, K., Gašparović, M., and Radić, F.: Floodplain vegetation and channel dynamics of a dam-impacted large lowland river: Satellite-based study of the Drava River, Croatia, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-6711, https://doi.org/10.5194/egusphere-egu26-6711, 2026.
Climatic variables as well as geological and biotic factors in the Alps have been recorded for decades by various sensors with increasing spatial, spectral and temporal resolution. A changing climate has clearly triggered morphological (hillslope and river dynamics) and biotic (vegetation cover and production) responses. However, understanding these dynamics well enough to predict future changes in coupled bio-geo-systems such as pore fluid pressure, landsliding, and vegetation, remains challenging. Changes in the system dynamics itself cannot be directly observed in remote sensing time series but have to be inferred from climate variables in combination with local factors (e.g. topographic metrics, lithology, vegetation cover).
We employ Google Earth Engine (GEE) and its wealth of freely available topographic, climate, and satellite datasets to compute spatiotemporal gradients of biotic and abiotic factors across the Eastern Alps. Using GEE's Python interface and the novel high-performance computing facility at University of Salzburg, we implemented a swath profile modelling framework that applies a curvilinear approach with signed distance metrics to capture variability across complex mountainous terrain. While previously only applied at local or regional scales, this study provides the first orogen-scale, swath-profile based assessment of spatial and temporal gradients across the Eastern Alps.
Our analysis quantifies past, present, and the projected changes in precipitation, temperature, and vegetation patterns, identifying regions of high landscape sensitivity. These results improve our understanding of climate-driven variability in the European Alps and establish a solid basis for future orogen-scale analyses of spatiotemporal gradients.
How to cite: Wilks-Stebbings, H., Robl, J., Meier, W., Tribsch, A., Trutschnig, W., and Hergarten, S.: Spatiotemporal Gradients of Environmental Forcing across the Eastern Alps: Quantifying Drivers of Landscape and Ecosystem Dynamics, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-5449, https://doi.org/10.5194/egusphere-egu26-5449, 2026.
In recent decades, greening has been a widely observed phenomenon across the European Alps, and the importance of biogeomorphic feedbacks in mountain environments has been increasingly recognised. Yet, research remains limited on the extent to which these vegetation changes interact with geomorphic activity and slope stability at catchment scale. Understanding these interactions is essential for improving interpretation of the development of alpine landscapes under ongoing climate forcing, as they influence sediment redistribution, slope stability and downstream ecosystem functioning.
This research investigates how these vegetation-slope dynamics interact in alpine environments, with particular focus on the development of the treeline ecotone, species-specific contributions to greening and the control of landform-specific variations on vegetation dynamics. We focus on the Meretschi catchment, a geomorphically dynamic valley in the Swiss Alps. Greening is quantified using NDVI from Landsat imagery (1984-2024) and tree establishment mapping in the treeline ecotone from historical orthophotos. Species-level field surveys were conducted, terrain variables were derived from a digital elevation model, and a detailed geomorphological map was constructed. All these aspects were compared across space and time to assess the controls on greening and their interactions.
Vegetation greening, indicated by NDVI increase, was strongest between 1900-2500 m, coinciding with the treeline ecotone. Tree establishment shifted upslope and intensified over time, with densification in localised microclimatic patches contributing more to greening. Clusters of more than 20 trees contributed significantly more to greening, highlighting the importance of both tree density and establishment rate.
Species contributions varied, with Larix decidua dominating greening among newly establishing trees compared to Pinus cembra. Across the catchment, woody vegetation (dwarf shrubs and forest) contributes more to greening than grassland and pioneers only recently started contributing. These patterns appear to be largely controlled by species functional traits and microclimatic sensitivities, but also by anthropogenic effects, in particular grazing practices.
Geomorphic activity strongly influenced greening, with more stable landforms with high soil development potential showing more pronounced greening compared to rocky, unstable landforms, and with gravitational landforms displayed the highest variability. This variability reflects episodic disturbance and recovery, which highlights the impact of biogeomorphic feedbacks.
Overall, the research shows that alpine greening in the Meretschitälli catchment develops from a synthesis of climatic facilitation, species traits, geomorphic activity and anthropogenic influence, producing spatially heterogeneous vegetation change. By linking greening to geomorphic activity and characteristics, this research advances our understanding of catchment-scale eco-geomorphic feedbacks and provides a basis for predicting how vegetation-slope-species interactions may shape alpine landscape with ongoing climatic changes.
How to cite: van Elswijk, L., Duurkoop, L., Kraaijenbrink, P., and Eichel, J.: Complex Greening in the Meretischitälli Catchment, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-10669, https://doi.org/10.5194/egusphere-egu26-10669, 2026.
Measuring and predicting sediment transport is a fundamental objective of geomorphology, yet research in rivers focusses almost exclusively on the transport of mineral sediment by water. In reality, material transported over river beds also includes organic sediment and is transported both hydraulically and through the actions of animals. Caddisfly (Trichoptera) are a widespread aquatic insect group which transport sediment over river beds in the form of case bioconstructions. While mineral sediment typically requires high discharge to mobilise, organic material and animal transported sediment may occur under any flow, potentially accounting for a significant proportion of total river bedload. Here, we measure bedload transport for a UK river and partition the contributions of mineral grains, organic materials and case-building caddisfly. Sampling was conducted every two months for a year and captured low-medium discharge conditions.
For particles >2 mm, organic material contributed approximately 50% of total bedload transport, with strong seasonal variation, peaking in autumn. Finer size fractions were dominated by mineral sediment. Caddisfly-transported sediment consisted primarily of medium to coarse sand (D₅₀ = 0.91 mm) and accounted, on average, for 30% of bedload transport of this size fraction, equivalent to 1.27 g m⁻¹ day⁻¹ (465 g m⁻¹ yr⁻¹). Caddisfly contributions were especially important during very low flows when hydraulic sediment transport was minimal. These results demonstrate that invertebrate activity can play a significant role in bedload transport, particularly under low-flow conditions, by altering both the magnitude and grain-size distribution of transported sediment. Our findings highlight the importance of explicitly incorporating biological processes into our understanding of sediment dynamics in rivers.
How to cite: Mason, R., Sanders, C., Johnson, M., Wood, P., and Rice, S.: Animal, vegetable or mineral? The relative contributions of hydraulic and animal-mediated transport to bedload in a gravel-bed stream, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-21416, https://doi.org/10.5194/egusphere-egu26-21416, 2026.
Before humans took on a dominant role in modifying streams and floodplains, native species were the primary agents of ecosystem engineering and surface change within river-floodplain systems. These natural, pre-human condition of European rivers and their floodplains remains poorly understood. In periods when human activity became a major driver of river and floodplain evolution, it is often difficult to distinguish between human and faunal impacts, especially in the absence of clear physical evidence. In this pilot study, we aim to reconstruct the pre-human environmental conditions of low-order streams and their floodplains in central Europe. We also develop a methodology to identify the dominant ecosystem engineers at specific riparian sites. Three research sites in central Europe were selected, where we reconstruct palaeo-environmental conditions using a combination of sedimentary ancient DNA (sedaDNA), botanical macroremain analysis, and chrono-stratigraphy to detect the presence or absence of key wetland plant species. Additionally, we investigate the presence of key animal ecosystem engineers which are now globally or locally extinct but were once critical to the functioning of sustainable riparian ecosystems. Identifying when and where these species were present will not only enhance our understanding of natural, resilient riparian conditions but also provide a baseline for interpreting subsequent human-environment interactions.
How to cite: Larsen, A., Nota, K., van der Sleen, P., Brouwers, T., Ramirez-Cortes, B., Sperisen, C., Kleijwegt, Z., and Vernot, B.: Using sedimentary ancient DNA to identify past ecosystem engineering in rivers, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-15208, https://doi.org/10.5194/egusphere-egu26-15208, 2026.
Ghost nets - abandoned, lost or discarded (ALD) fishing nets – account for a significant anthropogenic pressure on coastal geomorphic systems, negatively affecting benthic habitats and marine life. This study investigates the potential for efficient detection of ghost nets in shallow water coastal environments using high-resolution orthophotos in Lillebælt, Denmark from 2021 to 2025 (Andersen et al., 2026).
The primary method applied was visual interpretation of annual orthophotos generated by the Danish Agency for Climate Data based on aerial photos recorded in spring and autumn from 2021 to 2025 with a spatial resolution of approximately 10–12 cm. Morphometric analyses on airborne lidar bathymetry (ALB) data were integrated to support the identification of ghost nets. Ground-truth data for validation consisted of remotely operated vehicle (ROV) video footage and removal of nets in selected areas.
A total of 73 ghost nets were identified and assigned a confidence level ranging from one (uncertain) to three (certain). Approximately 30% of the detected nets were classified with high confidence (level three), while 46% were assigned confidence level two. In total, 64 of the 73 appointed nets were verified through ROV observations and net removal campaigns (North Nature, 2026). Further analyses revealed that ghost nets affect local vegetation coverage as well as local seabed erosion and deposition.
The results demonstrate that high-resolution orthophotos provide a cost-effective and time-efficient tool for detecting ghost nets in shallow coastal waters. A relatively high temporal resolution of imagery enhances detection capabilities and may support targeted mitigation efforts, contributing to reducing negative impacts on coastal ecosystems.
This project highlights the potential of integrating airborne remote sensing data (orthophotos and bathymetry) and ROV validation data to assess human-induced pressures on coastal environments at local to regional scale.
Acknowledgements
The project was funded by the Danish Environmental Protection Agency. The verification and removal of ghost nets were carried out by Nature North for the Danish Environmental Protection Agency in November 2025.
References
Andersen MS, Larsen IR, Nielsen NLJ, Hansen LØ, Larsen M, Andersen SB, Rödel L-G, Al-Hamdani Z & Ernstsen VB (2026). Near coastal seabed mapping in Lillebælt 2024-2025 (in Danish). GEUS Report for the Danish Environmental Protection Agency.
North Nature (2025). Removal of ghost nets in Lillebælt (in Danish). North Nature Report for the Danish Environmental Protection Agency.
How to cite: L. J. Nielsen, N., S. Andersen, M., R. Larsen, I., Ø. Hansen, L., N. Blok, C., Al-Hamdani, Z., and B. Ernstsen, V.: Spotting ghost nets from above - Airborne imaging to detect ALD fishing nets in shallow water in Lillebælt, Denmark, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-18090, https://doi.org/10.5194/egusphere-egu26-18090, 2026.
Landscape evolution continuously reshapes habitat availability, heterogeneity, and connectivity, thereby influencing patterns of biodiversity, endemism, and ecosystem resilience. Over geological timescales, surface processes such as uplift, erosion, and river capture generate spatially complex mosaics of habitats, while simultaneously creating barriers that isolate populations and alter connected pathways. Despite their central role in structuring ecological patterns, local geomorphic controls are rarely quantified explicitly in biodiversity analyses. Here, we present a framework to quantify how geomorphic processes shape habitat, isolation, and transience. The framework is applied across contrasting geomorphic and climatic settings, including the tropical Andes (Puracé National Natural Park, Colombia), a volcanic oceanic island (Gran Canaria, Canary Islands, Spain), and tectonically active arid mountain landscapes (California, USA).
We derived landform-based habitat patches by integrating multi-scale topographic position index classes and slope to explicitly capture the imprint of long-term surface processes and incorporated temperature and water-balance variables (CHELSA) to approximate the climatic constraints of the landscape. Vegetation was evaluated using an independent, remote-sensing–based product, derived by clustering multispectral imagery, vegetation indices, and canopy height. The landform-based habitat patches and remote-sensing-based vegetation product were verified using an official vegetation map from each region as independent biological reference. The isolation of the habitat patch classes is quantified from spatial connectivity using geomorphic barriers such as valleys, rivers, and relief contrasts, while habitat patch transience is explored using activity-related geomorphic indicators that capture ongoing landscape reorganization.
By evaluating geomorphology–vegetation relationships across multiple regions, the framework uses isolation and transience metrics to distinguish stable habitat patches that constrain vegetation distribution from dynamically reorganizing patches that promote fragmentation and turnover. Preliminary analyses indicate that vegetation diversity, based on vegetation maps, within geomorphic habitat patches tends to be lower than regional diversity, suggesting that they capture a meaningful ecological structure. Association strength appears to increase with elevation, pointing to a potentially important role of climate–topography coupling. Using this approach the framework can assess habitat fragmentation and dynamics within a region, serving as a proxy for tectono-geomorphic influences on biodiversity.
How to cite: van Wees, R. M. J., Zong, S., Willett, S., Fang, X., and Pellissier, L.: A framework for assessing geomorphic control on habitat patch isolation and transience, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-21036, https://doi.org/10.5194/egusphere-egu26-21036, 2026.
Fluvial biogeomorphic feedbacks happen on multiple spatial and temporal scales, and between them within a nested, hierarchical organization of river systems. Entities such as reach or catchment are often used to place a study in a spatial and temporal context. While hydrogeomorphic units are well defined and operationalized in fluvial geomorphology (e.g., catchment, reach, geomorphic unit etc.), transferring this logic to biogeomorphic units is not straightforward because vegetation and other biota both respond to and actively modify hydrological and geomorphological processes on a wide range of scales potentially not matching with the ones of fluvial geomorphology. Thus, such units inherently reflect the complex nature of riverine process regimes. Considering the two-way interactions of hydro-morphology and vegetation makes the delineation of (fluvial) biogeomorphic units of specific spatial and temporal scales particularly challenging.
With our contribution, we provide a synthesis of how hydrogeomorphic and biogeomorphic units have been defined in their spatio-temporal extent across literature from small entities with fast turnover rates to long lasting units like the catchment. We contrast (i) biogeomorphic units defined as standalone entities (e.g., pioneer or mature island), with (ii) biogeomorphic units defined as attributes or states of pre-defined geomorphic units (e.g., bars, islands, banks) within a hierarchical framework. Furthermore, we merge insights into the distribution of the units across scales with the phases of the Fluvial Biogeomorphic Succession model (geomorphic, pioneer, biogeomorphic and ecologic phase). We suggest that such integrated hierarchical perspective can guide research design and monitoring for management purposes.
How to cite: Lauermann, M., Pöppl, R., Heckmann, T., and Betz, F.: Revisiting fluvial biogeomorphic units across scales, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-13911, https://doi.org/10.5194/egusphere-egu26-13911, 2026.
The remote sensing model ‘Google4Habitat’ (Egger et al. 2024) enables large-scale vegetation classification based on freely available satellite imagery in combination with ground truth data. In a current project, it was further developed to predict hydrogeomorphology-driven vegetation succession phases at the Naryn River in Kyrgyzstan. This river has high hydrologic and morphologic dynamics over its entire length of 600 km (Betz et al. 2023). Additionally, drought stress due to the continental climate of Central Asia causes specific succession pathways (Lauermann et al. 2024). This makes the Naryn an interesting case study for demonstrating the capabilities of the ‘Google4Habitat’ model for analyzing the spatial pattern of vegetation communities and their biogeomorphic implications.
The ‘Google4Habitat’ model runs on the Google Earth Engine platform. By using globally available satellite data together with recorded reference points for each classified habitat type, it performs a spatial and temporal analysis for each habitat. Specifically, Sentinel-2 scenes from one year are selected and monthly spectral values and vegetation indices are calculated. Orthophotos are integrated and texture parameters are added. Pixel values at training points are used to create the classification model (358 collected in the field, supplemented by 987 points from aerial image interpretation), which is then validated, evaluated, and used to create the classification map of the study area. To obtain precisely delineated habitat maps, a segmentation of habitat structures is carried out based on a high resolution orthophoto. Then, the classification map is intersected with the segments and final habitat types are assigned using zonal statistics. The habitat map is intersected with the three succession series delineated on the orthophoto and area balances are created.
On the Naryn River, nine different habitat types were obtained using this supervised classification approach. The freshly to moderately dry sites of the sedimentation series are characterized by pioneer vegetation located within the active channel, Salix-Myricaria shrub, and softwood riparian forests of varying ages with Populus talassica, as well as extensive Hippophae shrubs. The shallow sites of the aggradation series are, however, much more sparsely vegetated than the sedimentation series and are characterized by the presence of Tamarix ramosissima. Both series end with an Artemisia steppe. Finally, the siltation series is characteristic of the former side arms that are in the process of silting up and are particularly dominated by Typha minima and Phragmites australis.
References
Betz, F., Lauermann, M., & Egger, G. (2023). Biogeomorphology from space: Analyzing the dynamic interactions between hydromorphology and vegetation along the Naryn River in Kyrgyzstan based on dense satellite time series. Remote Sensing of Environment, 299, 113890.
Egger, G., Preinstorfer, S., Kollmann, M., Becker, I., Izquierdo-Verdiguier, E. & Paul, P. (2024). Google4Habitat - a novel method for remote sensing-based habitat classification using Google Earth Engine. Carinthia II, 3/1, 8–28.
Lauermann, M., Heckmann, T., Poeppl, R., Egger, G., Eichel, J. & Betz, F. (2024). How does Hydrological Connectivity Influence Fluvial Biogeomorphic Succession in Semiarid Regions? A Case Study from the Naryn River in Kyrgyzstan, Central Asia. AGU Fall Meeting 2024, Poster No. 1302, EP43C-1302.
How to cite: Egger, G., Becker, I., Damm, C., Lauermann, M., and Betz, F.: Remote sensing-based classification of floodplain vegetation along the Naryn River, Kyrgyzstan, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-7587, https://doi.org/10.5194/egusphere-egu26-7587, 2026.
Mountain regions are globally recognized as biodiversity hotspots, yet habitat heterogeneity alone cannot fully explain their exceptional diversity. During orogeny, horizontal and vertical tectonic forces, as well as surface erosion, act on the landscape, generating dynamic, transient landscapes with reorganizing drainage networks and changing topography. Because aquatic habitats are tightly coupled with river topography, freshwater species are particularly insightful to study how landscape evolution influences biodiversity.
In this study, we investigated freshwater fish diversity in northern Taiwan, a tectonically active area with high island endemism. Taiwan is dominantly a convergent orogenic belt. However, an exception is the NE corner of the island, where extension associated with the Okinawa back-arc basin has propagated on land. Active crustal stretching and subsidence with normal faulting has resulted in formation of the Ilan Plain and a new drainage system. The largest river in this system is the Lanyang River, which flows parallel to the mountain belt, along an active normal fault system. To investigate if and how basin formation and drainage reorganization impact biodiversity, we collected environmental DNA (eDNA) from 22 riverine sites within and surrounding the Lanyang River basin. We amplified a 420 bp fragment of the mtDNA cytochrome B (cytB) gene and denoised the sequences to retrieve amplicon sequence variants (ASVs). We then examined variations in richness and assemblage composition among basins (interspecific), as well as within one endemic genus (intraspecific).
Our results reveal clear geographic patterns, indicating the existence of geographic barriers, as well as dispersal corridors. The Lanyang River basin emerged as a distinct biodiversity hotspot, with patterns of interspecific and intraspecific diversity suggesting that its high richness has been generated through repeated influx of genetic material from neighboring basins. These patterns are consistent with a history of river capture events driven by drainage divide migration as the Lanyang River basin has increased in size by headwater growth, highlighting how coupled tectonic and geomorphic processes act to shape freshwater fish diversity.
How to cite: Krug, C., Chen, I., Pellissier, L., and Willett, S. D.: Coupled tectonic and geomorphic forces create a local fish diversity hotspot, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-19145, https://doi.org/10.5194/egusphere-egu26-19145, 2026.
The Oceano Dunes in San Luis Obispo County, California, is a known source of fugitive dust emissions. Under conditions of elevated wind speed exceedances of the US Federal standard (150 μg m−3) and the State of California standard (50 μg m−3) for 24-hour time-integrated concentrations of particulate matter ≤10 μm aerodynamic diameter (PM10) have been observed downwind of the dunes. Part of the dune system lies within the Oceano Dunes State Vehicular Recreation Area (ODSVRA) and the off-highway recreational activity on the dune areas is known to augment dust emission potential. A Stipulated Order of Abatement (SOA) requires the California Department of Parks and Recreation to reduce the PM10 attributable to the ODSVRA lowering the potential health risk for people living downwind. As amended in 2022, the SOA requires that by the end of 2028, PM10 emissions from the ODSVRA be reduced to those modeled to approximate the conditions that existed in 1939. This is prior to high levels of off-highway vehicle (OHV) activity. The SOA requires that the annual modeling evaluation show that the total emissions (tonnes day-1) of the current year be less than the total emissions from the 1939 scenario for the same meteorological conditions. As of July 1, 2024, Parks achieved compliance with the SOA. Compliance with the SOA has also been reported for 2025. To reduce regional PM10 levels has required direct intervention of this dynamic geomorphic system by implementing dust abatement management efforts, based largely on planting of vegetation and re-establishing a foredune area.
We use 14-years of hourly PM10 (µg m-3) concentration and wind data to quantify the change in hourly PM10 concentration that has resulted from the evolution of dust management methods implemented from 2013 through 2025. Here we demonstrate that the PM10 concentrations downwind of the ODSVRA are lower now, for similar wind conditions, than prior to the establishment of dust controls. Additionally, a machine learning regression approach, based on the Random Forest (RF) algorithm, was used to evaluate how effective dust management was for reducing the potential number of exceedances of the State and Federal air quality standards compared to the number of exceedances prior to 2013, i.e., before the implementation of the dust management program.
How to cite: Gillies, J., Furtak-Cole, E., Henao, J., and Mejia, J.: Dust Control Management Methods Achieve Air Quality Objectives, Oceano Dunes State Vehicular Recreation Area, Oceano CA, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-8439, https://doi.org/10.5194/egusphere-egu26-8439, 2026.
Geomorphology provides the potential to design new landforms based on understandings of hydrology and sediment transport. An example of this need are post mining landscapes where large areas (hundreds of hectares) are disturbed. Post-mining landscapes require reconstruction to support an agreed landuse. The landscape also requires integration with underlying materials and surrounding unmined or undisturbed catchments with consideration of the post-mining land use. At many sites, pre-mine landscapes with hillslope curvature are replaced with linear hillslopes. These landscapes are easy to construct and result in a surface which can be easily traversed by agricultural machinery, while the benches often rely on drainage control structures to manage runoff and resultant erosion. An alternative to linear hillslopes is to employ a catchment focus for post-mining landscape shape using an understanding of geomorphology. Here, a new method for catchment design is presented where a computer-based Landscape Evolution Model (LEM) is used to design the post-mining landscape. The LEM employs site and material specific hydrology and erosion parameters which produce a landscape which potentially represents the geomorphological evolution of the catchment and also has a more natural appearance. Results demonstrate that a computer generated landscape produces sediment output within that of target erosion rates with low gully depths.
How to cite: Hancock, G., Martin-Duque, J., and Coulthard, T.: Using Landscape Evolution Models to create new catchments, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-3655, https://doi.org/10.5194/egusphere-egu26-3655, 2026.
Soil transport through the turning of root systems of uprooted trees represents a crucial soil disturbance agent in many forest ecosystems. In addition to tree species and forest structure, treethrow dynamics strongly depend on the character of wind flow and specifically on extreme wind events. Extreme cyclonic flow is typically west-east in Europe and causes major pulses in forest slope dynamics. In the regime of rare but powerful winds alternating with long periods of disordered flow, slope exposure can be a significant geomorphological driver. Slope orientation can hypothetically affect the frequency of uprooting events and the direction of tree fall relative to the fall line. The long-term effect is a different trajectory of soil evolution and different slope dynamics. Tree orientation determines how much of the uprooted soil will return to the treethrow pit and how much will be eroded. These aspects were explored for the first time using extensive repeated tree census data spanning from 1975 to 2007, collected in the Žofínský Primeval Forest Reserve in the Novohradské Mountains, Czech Republic. We analyzed the differences between the spatial configuration and biogeomorphic potential of uprootings under two scenarios: extreme windthrow related to a strong disturbance event and selective uprooting associated with forest gap dynamics. Wind data observations (direction and speed) were used to define the relationship between uprooting intensity and spatiotemporal linkages of uprootings' tree stems features (azimuths) with wind and terrain properties (elevation and aspect).
We found differences in tree stem azimuths of uprootings, in their spatial configuration against elevation contour lines, and terrain aspect for two classes – upslope and downslope uprootings, and two forest developmental trajectories – dominated by gap formation (selective), and excessive (extreme) damage caused by the Kyrill storm in January 2007. Azimuths of uprootings followed prevailing wind directions, suggesting this metric can be used as a bioindicator of wind properties in places without standard meteorological measurements. Norway spruce (Picea abies) was the most commonly uprooted and broken tree species, and its damage rate increased during the Kyrill windstorm. Upslope uprooting was more common, potentially involving a higher volume of soil mass being subjected to mixing than erosion.
Our results indicate that slope aspect influences the path of old-growth forest development and soil formation. It happens repetitively during extreme wind events (pulses of energy "injected" to forest ecosystems by wind currents of extreme speeds and specific directions), acting occasionally but with great force over the European land. It is essential to emphasize the synergistic and critical impact of geomorphic features such as slope aspect and strong wind events on soils and forests, particularly in the context of the anticipated increase in the extremity of various climate parameters, including wind speed and the frequency of strong winds.
The study has been supported by the Czech Science Foundation (project No. 24-11119S).
How to cite: Pawlik, Ł., Šamonil, P., Kral, K., Adam, D., and Godziek, J.: Strong wind patterns and slope surface exposure change the biogeomorphological component of the soil transport and development in old-growth temperate forests, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-12243, https://doi.org/10.5194/egusphere-egu26-12243, 2026.
Carbon redistribution along with accelerated erosion in agricultural landscapes is an important component of the global carbon cycle. However, it remains largely untested whether soil particles and soil organic carbon (SOC) are always preserved synchronously across hillslopes, and what mechanisms govern potential decoupling. In hilly Northeastern China, carbon-rich black soils have experienced only recently severe agriculture-induced erosion over the past ~130 years, providing an ideal setting to examine sediment and carbon behaviour over the Holocene and to assess how accelerated anthropogenic erosion influences long-term carbon dynamics. In this study, we investigated single-grain post-infrared infrared stimulated luminescence (pIRIR) signals of feldspar along two black soil catenae with contrasting slopes. 31 luminescence samples collected from five soil profiles along a catena with a slope gradient of 0.37°, 19 luminescence samples from three soil profiles along a catena with a slope gradient of 1.91°. Geochronological constrains from luminescence and 137Cs were combined with soil properties to trace soil redistribution and reconstruct Holocene erosion phases along the catenae. We identified a clear topographic control on whether sediment and carbon are redistributed synchronously. On gentle slopes, colluvial deposits formed primarily at backslope positions, yet no buried carbon horizons were preserved. This decoupling results from prolonged soil residence times for sufficient bioturbation , as indicated by abundant krotovina and distinct equivalent dose (De) distributions between krotovina and non-krotovina samples from same depth (~80 cm) in the summit profile. In contrast, steeper slopes favour rapid deposition and carbon burial at toeslope position due to higher erosion relative to soil mixing. Overall, our findings demonstrate that topography and post-depositional bioturbation jointly determine whether sediment flux translates into long-term carbon preservation. Gentle slopes promote redistribution without carbon burial, while steeper slopes facilitate synchronous sediment and carbon accumulation. This contrast is further amplified by anthropogenic erosion, leading to situations in which sediment transported is enhanced while carbon burial lags behind. These results highlight the critical role of landscape configuration and biological processes in mediating carbon fate in cultivated soils and emphasize the need to account for such controls when quantify carbon dynamic under human-induced erosion.
How to cite: Pan, X., Reimann, T., van der Meij, W. M., Yang, F., and Zhang, G.: When Sediment Moves but Carbon Lags: Topography and Bioturbation Control Soil Carbon Burial jointly, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-19810, https://doi.org/10.5194/egusphere-egu26-19810, 2026.
Posters virtual: Tue, 5 May, 14:00–18:00 | vPoster spot 3
EGU26-5549 | ECS | Posters virtual | VPS26
Can vegetation root simulation in the laboratory lead to better understanding of flow-vegetation interactions?Tue, 05 May, 14:54–14:57 (CEST) vPoster spot 3
Study of flow-vegetation interactions in river channels is necessary to comprehend its importance in sediment transport and morphological changes. Numerous laboratory experiments, numerical modelling, and field data have been collected and analyzed by researchers throughout decades. Previous laboratory experiments simulating vegetation majorly studied the impacts from vegetation shoot width and density. However, studies showed that along with the shape and size of vegetation, root-soil binding capacity also plays an important role in the morphological changes in the channel. To test this theory, we conducted experiments using a flume of 15 m in length and 1.8 m in width at the University of British Columbia. The main channel and floodplain width considered is 60 cm each. Two sets of experiments with and without vegetation roots in the floodplains were conducted. 3D printer was used to model the floodplain vegetation (see Figure). In the case of vegetation with roots, we considered it as a taproot system with a spiral structure attached to the simple root-shoot system as seen in the figure. Preliminary tests showed vegetation with roots was able to sustain the force of flow in different discharges in a better way without getting uprooted compared to vegetation without roots. Furthermore, there is also a difference in the morphology of the channels between the with and without roots experiments. The initial study showed that incorporating vegetation roots in the laboratory provides a more effective means of understanding flow-vegetation interactions and channel evolution. Furthermore, this study will also be helpful for the advancement of nature-based solutions like soil bioengineering techniques.
Simple root-shoot system Taproot-shoot system
How to cite: Barman, J. and Hassan, M.: Can vegetation root simulation in the laboratory lead to better understanding of flow-vegetation interactions?, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-5549, https://doi.org/10.5194/egusphere-egu26-5549, 2026.
