Search Results (136)

Glacial lakes in the Upper Indus Basin (UIB) are rapidly evolving due to accelerated glacier retreat driven by climate change. Here we present a comprehensive inventory of glacial lakes using Sentinel-1 SAR data with adaptive backscatter thresholding, enabling consistent detection under challenging conditions and improving delineation accuracy. In August 2023, we identified 6019 glacial lakes at scales from 0.001 to 5.80 km², covering a cumulative area of 266 km² (~0.06% of the basin). Although more than 90% of the lakes are smaller than 0.1 km², large lakes (>0.1 km²) account for over 57% of the total lake area. Most lakes are concentrated between 4000 and 4600 m, coinciding with the main glacierized zone. Regional patterns reveal that the Hindu Kush and Himalayas are dominated by glacier erosion lakes (GELs) and moraine-dammed lakes (MDLs), reflecting widespread glacier retreat, whereas the Karakoram is characterized by numerous supraglacial lakes (SGLs) associated with extensive debris-covered glaciers. Compared to previous optical-based inventories, our SAR-based approach captures more lakes and better represents small and transient features such as SGLs. These findings provide a more accurate baseline for assessing cryospheric change and glacial lake hazards in one of the world’s most heavily glacierized basins. Full article

Mountain glaciers are sensitive indicators of climate variability, and their retreat since the end of the Little Ice Age (LIA) has strongly reshaped alpine environments worldwide. In the Greater Caucasus, glacier shrinkage has accelerated over the past century, yet detailed multi-temporal reconstructions remain limited for many glaciers. Here, we reconstruct the post-LIA evolution of Tsaneri–Nageba Glacier, one of largest ice bodies in the Georgian Caucasus, and document the development of its newly formed proglacial lake. Using a combination of geomorphological mapping, historical maps, multi-temporal satellite imagery, Uncrewed Aerial Vehicle (UAV) photogrammetry, and sonar bathymetry, we quantify glacier change from ~1820 to 2025 and provide the first direct measurements of a proglacial lake in the Tsaneri–Nageba system—and indeed in the Georgian Caucasus as a whole. Our results reveal that Tsaneri–Nageba Glacier has shrunk from ~48 km² at its LIA maximum to ~30.6 km² in 2025, a loss of −43.5% (or −0.21% yr⁻¹). The pace of shrinkage intensified after 2000, with the steepest losses recorded between 2014 and 2025. Terminus positions shifted up-valley by nearly 3.9 km (Tsaneri) and 4.3 km (Nageba), accompanied by fragmentation of the former compound valley glacier into smaller ice bodies. Long-term meteorological records confirm strong climatic forcing, with pronounced summer warming since the 1990s and declining winter precipitation. A proglacial lake started to form in mid-summer 2015, which by 03/09/15 had a surface area of ~14,366 m², expanding to ~106,945 m² by 10/07/2025. The lake is in contact with glacier ice and is thus prone to calving. It is dammed by unconsolidated moraines and bounded by steep, active slopes, making it susceptible to generating a glacial lake outburst flood (GLOF). By providing the first quantitative measurements of a proglacial lake in the region, this study establishes a baseline for future monitoring and risk assessment. The findings highlight the urgency of integrating glaciological, geomorphological, and hazard studies to support community safety and water resource planning in the Caucasus. Full article

This study focused on the multifunctional characteristics and bioremediation potential of Paracoccus spp. A novel Gram-stain-negative, aerobic, non-motile, ellipsoidal bacterium, named Paracoccus qomolangmaensis S3-43^T, was isolated from moraine samples collected from the north slope of Mount Everest at an altitude of 6109 m above sea level (a.s.l.). To clarify the phylogenetic relationship of this strain within the Paracoccus genus and systematically characterize its features, analyses were conducted using polyphasic taxonomy and comparative genomics. Results revealed two distinct functional characteristics of strain S3-43^T: First, strain S3-43^T exhibits exceptional radiation resistance, particularly tolerance to ionizing radiation. Genome annotation indicates abundant DNA repair and antioxidant-related genes (e.g., vsr, mutL, mutS, ruvC, radA, addA, recA, recN, recO). Second, strain S3-43^T contained several pyrethroids degradation related genes, including cytochrome P450, monooxygenase, and aminopeptidase. The results of the genomic comparison of strain S3-43^T with related type strains also revealed differences and distribution of key genes related to stress response, environmental variables, and bioactive metabolites. Based on the results of the polyphasic taxonomic analysis, strain S3-43^T (=KCTC 8297^T = GDMCC 1.3460^T) should be classified as a novel species of the genus Paracoccus, designated as Paracoccus qomolangmaensis sp. nov. Full article

This work examines the occurrence of biological soil crusts (BSCs) on glacial foreland moraines and their relationship to other vegetative components of the post-glacial landscape. BSCs on moraines of all ages are biologically complex composites of cyanobacteria, mosses, lichens, liverworts, and fungi. The amount of surface cover by BSCs and other components of the successional communities vary approximately with the ages of the surfaces. During the pioneer successional stage, BSCs are more abundant than other community components and consist primarily of filamentous cyanobacteria. On the youngest moraines, vascular plants, with the exception of graminoids, occur exclusively where BSCs are present. On successively older moraines, the coverage by mosses and vascular plants generally increases while that of BSCs decreases, although substantial variations occur that are attributed to exposure to environmental factors, primarily wind. Overall successional patterns suggest an essential role of BSCs in facilitating vascular plant colonization mainly during the pioneer stage, likely through enhancement of soil moisture and nutrient availability. The importance of facilitation by BSCs appears to decrease on older moraines as BSCs are replaced or subsumed by vascular plants and mosses. Full article

Published cosmogenic ¹⁰Be exposure ages from the terminal moraine of the Laurentide Ice Sheet (LIS) in northeastern North America have been interpreted to date the start of the retreat of the LIS at the Last Glacial Maximum (LGM) about 25 thousand years ago (ka). In contrast, published ¹⁴C accelerator mass spectrometry (AMS) dates for terrestrial plant macrofossils in LIS basal deglacial clay deposits range back to only ~16 calibrated (cal) ka, more consistent with the timing of glacio-eustatic rise and associated meltwater discharge to the North Atlantic and Gulf of Mexico associated with LGM deglaciation. We apply statistical models of geomagnetic secular variation, including dipole moment, to the latitudinal scaling of cosmic ray flux to see how well the age discrepancy can be addressed. A preferred new scaling, which is essentially time-invariant over the relevant LGM age range, shifts the exposure ages only a few thousand years younger. The age discrepancy may thus stem more from potential local biases toward higher ¹⁰Be concentrations (older apparent ages) at the terminal moraine sites, such as much higher ¹⁰Be production rates at the LIS front, and especially from inheritance. Such biases can be tested by obtaining primary ¹⁰Be calibration sites in the LGM time frame, and by more comprehensive sampling strategies for glaciated terrain to discern inheritance. Full article

Glacial-lake outburst floods (GLOFs) threaten more than three million residents of south-east Kazakhstan, yet quantitative data on lake growth and storage are scarce. We inventoried 154 lakes on the northern flank of the Ile-Alatau and selected four moraine-dammed basins with the greatest historical flood activity for detailed study. Annual lake outlines (2016–2023) were extracted from 3 m PlanetScope imagery with a Normalised Difference Water Index workflow, while late-ablation echo-sounder surveys (2023–2024) yielded sub-metre bathymetric grids. A regionally calibrated area–volume power law translated each shoreline to water storage, and field volumes served as an independent accuracy check. The lakes display divergent trajectories. Rapid thermokarst development led to a 37% increase in the surface area of Lake 13bis, expanding from 0.039 km² to 0.054 km² over a 5-year period. In contrast, engineering-induced drawdown resulted in a 44% reduction in the area of Lake 6, from 0.019 km² to 0.011 km². Lakes 5 and 2, which are supplied by actively retreating glaciers, exhibited surface area increases of 4.8% and 15%, expanding from 0.077 km² to 0.088 km² and from 0.061 km² to 0.070 km², respectively. The empirical model reproduces field volumes to within ±25% for four lakes, confirming its utility for rapid hazard screening, but overestimates storage in low-relief basins and underestimates artificially drained lakes. This is the first study in Ile-Alatau to fuse daily 3 m multispectral imagery with ground-truth bathymetry, delivering an 8-year, volume-resolved record of lake evolution. The results identify Lake 5 and Lake 2 as priority targets for early-warning systems and demonstrate that sustained intervention can effectively suppress GLOF risk. Incorporating these storage trajectories into regional disaster plans will sharpen evacuation mapping, optimise resource allocation, and inform transboundary water-hazard policy under accelerating climate change. Full article

This article presents a comprehensive assessment of mudflow risk in the Talgar River basin through the application of Multi-Criteria Decision Analysis (MCDA) methods and numerical modeling using the Rapid Mass Movement Simulation (RAMMS) environment. The first part of the study involves a spatial assessment of mudflow hazard and susceptibility using GIS technologies and MCDA. The key condition for evaluating mudflow hazard is the identification of factors influencing the formation of mudflows. The susceptibility assessment was based on viewing the area as an object of spatial and functional analysis, enabling determination of its susceptibility to mudflow impacts across geomorphological zones: initiation, transformation, and accumulation. Relevant criteria were selected for analysis, each assigned weights based on expert judgment and the Analytic Hierarchy Process (AHP). The results include maps of potential mudflow hazard and susceptibility, showing areas of hazard occurrence and risk impact zones within the Talgar River basin. According to the mudflow hazard map, more than 50% of the basin area is classified as having a moderate hazard level, while 28.4% is subject to high hazard, and only 1.8% falls under the very high hazard category. The remaining areas are categorized as very low (4.1%) and low (14.7%) hazard zones. In terms of susceptibility to mudflows, 40.1% of the territory is exposed to a high level of susceptibility, 35.6% to a moderate level, and 5.5% to a very high level. The remaining areas are classified as very low (1.8%) and low (15.6%) susceptibility zones. The predictive performance was evaluated through Receiver Operating Characteristic (ROC) curves, and the Area Under the Curve (AUC) value of the mudflow hazard assessment is 0.86, which indicates good adaptability and relatively high accuracy, while the AUC value for assessing the susceptibility of the territory is 0.71, which means that the accuracy of assessing the susceptibility of territories to mudflows is within the acceptable level of model accuracy. To refine the spatial risk assessment, mudflow modeling was conducted under three scenarios of glacial-moraine lake outburst using the RAMMS model. For each scenario, key flow parameters—height and velocity—were identified, forming the basis for classification of zones by impact intensity. The integration of MCDA and RAMMS results produced a final mudflow risk map reflecting both the likelihood of occurrence and the extent of potential damage. The presented approach demonstrates the effectiveness of combining GIS analysis, MCDA, and physically-based modeling for comprehensive natural hazard assessment and can be applied to other mountainous regions with high mudflow activity. Full article

The water level of Lake Neuchâtel (Switzerland) was lowered 150 years ago, initiating soil formation and colonization by riparian forests of the previously submerged areas. Although the soils of the whole area are young and have probably quite similar parent material (lacustrine sediments and moraine), the present soils show a large diversity of horizon structures and contents. The aim of this study is to describe the respective processes of accumulation, integration, and stabilization of organic matter and assess the soil variables influenced by these processes in the various types of riparian forests with different moisture levels. The investigation employed a semi-quantitative, holistic approach that combined field observations, laboratory analyses, and micromorphological examination of soil thin sections. The results indicate that the accumulation and stabilization of organic matter are primarily governed by physicochemical factors associated with the parent material, particularly soil texture and calcium cation saturation. Soil moisture and groundwater elevation were found to mainly influence biological activity and vegetation types. Additionally, the incorporation of organic matter is affected by both soil texture and bioturbation processes. Overall, this study underscores the complexity of the mechanisms regulating organic matter dynamics in young soils. Full article

With ongoing global warming, glacier lake outburst floods (GLOFs) and associated debris flows pose increasing threats to downstream communities and infrastructure. Glacial lakes differ in their triggering factors and breach mechanisms, necessitating event-specific analysis. This study investigates the GLOF risk of Jiongpuco Lake, located in the southeastern part of the Tibetan Plateau, using an integrated approach combining remote sensing, field surveys, and numerical modeling. Results show that the lake has expanded significantly—from 2.08 km² in 1990 to 5.43 km² in 2021—with the most rapid increase observed between 2015 and 2016. InSAR data and optical imagery indicate that surrounding moraine deposits remain generally stable. However, ice avalanches from the glacier terminus are identified as the primary trigger for lake outburst via wave-induced overtopping. Mechanical and geomorphological analyses suggest that the moraine dam is resistant to downcutting erosion, reinforcing overtopping as the dominant failure mode. To assess potential impacts, three numerical simulation scenarios were conducted based on different avalanche volumes. Under the extreme scenario involving a 5-million m³ ice avalanche, the modeled peak discharge at the dam site reaches approximately 19,000 m³/s. Despite the high flood magnitude, the broad and gently sloped downstream terrain facilitates rapid attenuation of flood peaks, resulting in limited impact on downstream settlements. These findings offer critical insights for GLOF hazard assessment, disaster preparedness, and risk mitigation under a changing climate. Full article

This study assesses the risks of glacial lake outburst floods (GLOFs) from moraine sediment dams around Gurudongmar Lake in the Northern Sikkim Himalayas at an elevation of 17,800 feet. It focuses on three moraine sediment dams, analysing the implications of slope failure on the upstream side and the downstream stability under steady seepage conditions, as well as the risks posed by permafrost thawing. Using a comprehensive methodology that includes geotechnical evaluations, remote sensing, and digital elevation models (DEMs), the research employs finite element analysis via PLAXIS2D for the stability assessment. The main findings indicate a stratification of sediment types: the upper layers are loose silty sand, while the lower layers are dense silty sand, with significant variations in shear strength, permeability, and other geotechnical properties. Observations of solifluctions suggest that current permafrost conditions enhance the dams’ stability and reduce seepage. However, temperature trends show a warming climate, with the average days below 0 °C decreasing from 314 (2004–2013) to 305 (2014–2023), indicating potential permafrost thawing. This thawing could increase seepage and destabilise the dams, raising the risk of GLOFs. Numerical simulations reveal that scenarios involving water level rises of 5 and 10 m could lead to significant deformation and reduced safety factors on both the upstream lateral dams and downstream front dams. The study emphasises the urgent need for ongoing monitoring and risk assessment to address the potential hazards associated with GLOFs. Full article

Understanding glacier and climate variations since pre-Industrial times is crucial for evaluating the present-day glacier response to climate change. Here, we focus on twelve small glaciers (≤2.0 km²) on both the northern and southern slopes of the Greater Caucasus to assess post-Little Ice Age glacier–climate fluctuations in this region. We reconstructed the Little Ice Age glacier extent using a manual detection method based on moraines. More recent glacier fluctuations were reconstructed using historical topographical maps and satellite imagery. Digital elevation models were used to estimate the topographic characteristics of glaciers. We also used the accumulation area ratio (AAR) method and a regional temperature lapse rate to reconstruct glacier snowlines and corresponding temperatures since the 1820s. The results show that all selected glaciers have experienced area loss, terminus retreat, and equilibrium line altitude (ELA) uplift over the last 200 years. The total area of the glaciers has decreased from 19.1 ± 0.9 km² in the 1820s to 9.7 ± 0.2 km² in 2020, representing a −49.2% loss, with an average annual reduction of −0.25%. The most dramatic reduction occurred between the 1960s and 2020, when the glacier area shrank by −35.5% or −0.59% yr⁻¹. The average terminus retreat for all selected glaciers was −1278 m (−6.4 m/yr⁻¹) during the last 200 years, while the average retreat over the past 60 years was −576 m (−9.6 m/yr⁻¹). AAR-based (0.6 ± 0.05) ELA reconstructions from all twelve glaciers suggest that the average ELA in the 1820s was about 180 m lower (3245 ± 50 m a.s.l.) than today (3425 ± 50 m a.s.l.), corresponding to surface air temperatures <1.1 ± 0.3 °C than today (2001–2020). The largest warming occurred between the 1960s and today, when snowlines rose by 105 m and air temperatures increased by <0.6 ± 0.3 °C. This study represents a first attempt at using glacier evidence to estimate climate changes in the Caucasus region since the Little Ice Age, and it can be used as a baseline for future studies. Full article

Anemone altaica Fisch. ex C. A. Mey., a component of the tertiary boreo-nemoral vegetation complex, exhibits a disjunct distribution from European Russia to Central China. The Khamar-Daban Ridge, extending along Lake Baikal’s southern coast, has served as a refugium preserving mesophilic forest remnants in South Siberia since the Pleistocene. This study aimed to elucidate the phylogenetic relationships and historical biogeography of A. altaica within the Khamar-Daban refugium using plastid DNA markers (trnL + trnL-trnF). Phylogenetic and mismatch distribution analysis revealed polyphyly (more specifically diphyly) among A. altaica lineages, suggesting past hybridization events with related species followed by backcrossing. Estimation of isolation by distance effect, spatial autocorrelation analysis, PCoA, and AMOVA indicated a clear spatial genetic structure for A. altaica on the Khamar-Daban Ridge. The most reliable geographical model suggests that during periods of Pleistocene cooling, A. altaica persisted in at least six microrefugia within the ridge. Populations associated with these microrefugia formed western, central, and eastern genetic supergroups with limited gene flow among them. Gene flow likely occurred more easily during glaciations or early interglacials when the subalpine zone shifted closer to Lake Baikal due to the depression of the snow boundary, allowing adjacent populations to intermingle along the glacial edges and terminal moraines in mountain forest belt. Full article

Investigations of CO₂ emissions in the context of different tillage systems are relevant not only for studying the effects of climate change but also for evaluating the sustainability of soil management. To better understand the influence of soil physico-chemical properties on CO₂ emissions, an experiment was conducted to measure the direct and indirect effects of these soil properties on CO₂ efflux. Soil CO₂ efflux is measured using a closed chamber method (LI-COR LI-8100A) under various tillage in two soil textures. Our research revealed that soil temperature, water content, soil organic carbon, total nitrogen, available phosphorus and pH significantly affected the soil–atmosphere CO₂ exchange rate. Soil CO₂, volumetric water content and soil temperature were higher in loam soil than in sandy loam soil. Soil CO₂ efflux was 8.6% lower in conventional tillage than under reduced and no tillage. Total nitrogen and soil organic carbon contents are dependent on tillage and decreased from no tillage to conventional tillage. Soil agrochemical properties such as SOC, total nitrogen, available phosphorus, available potassium and soil pH were higher evaluated in loam soil than in sandy loam soil. The results of this research are valuable contributions to knowledge on soil management in relation to CO₂ emissions on morainic loamy soil. Full article

Shielings are seasonal settlements found in upland pastures across Scandinavia and the North Atlantic. New investigations in the county of Møre and Romsdal, Norway, demonstrate the existence of this transhumant system by the Viking Age and Early Middle Ages. Sub-terranean features in these pastoral mountain landscapes have been identified by remote sensing technologies, but non-invasive methods still face challenges in terms of practical applicability and in confirming the presence of archaeological sites. Generally, aerial surveys, such as LiDAR and image-based modelling, excel in documenting visual landscapes and may enhance detection of low-visibility features. Thermography may also detect shallow subsurface features but is limited by solar conditions and vegetation. Magnetic methods face challenges due to the heterogeneous moraine geology. Ground-penetrating radar has yielded better results but is highly impractical and inefficient in these remote and rough landscapes. Systematic soil coring or test-pitting remain the most reliable options for detecting these faint sites, yet non-invasive methods may offer a better understanding of the archaeological contexts—between the initial survey and the final excavation. Altogether, the study highlights the dependency on landscape, soil, and vegetation, emphasising the need to consider each method’s possibilities and limitations based on site environments and conditions. Full article

Terrestrial small mammal species typically assemble according to plant communities, but multiple factors, including large-scale geographic patterns, influence their assemblage structure. Despite their ecological significance, small mammals are often underrepresented in biodiversity assessments, and many Polish national parks lack comprehensive surveys. This is also the case for Wolin National Park (WNP), Poland’s only national park on a coastal marine island, which is known for its unique bat fauna. Here, we surveyed small mammals in WNP using live and pitfall trapping, identifying only nine species—the lowest richness among the five regional national parks (which host 11–13 species based on trapping data alone). Rarefaction analysis indicated a very low probability of detecting additional species with further sampling. This unexpectedly low richness is likely linked to insular isolation and the park’s location at the edge of the regional distributions of three species. Cluster analysis revealed a key pattern in WNP’s small mammal assemblages: a division between two distinct landscape units—moraine hills and the alluvial delta—where Apodemus flavicollis and Apodemus agrarius were the predominant species, respectively. This division had a greater influence on assemblage clustering than local vegetation. Full article