Search Results (141)

Cushion plants, renowned for their resilience to alpine and arctic extremes, remain challenging to delineate at the species level due to dense interwoven canopies and high spectral similarity among species. This study introduces CryoFlora, an instance segmentation framework tailored to cushion species, integrating a large-kernel attention backbone, UniRepLKNetBlock, with a bidirectional attention-based fusion neck, BIMAFPN, to enhance feature representation and boundary precision. CryoFlora was trained on 528 annotated UAV image tiles containing 17,488 instances of Thylacospermum caespitosum and Rhodiola rosea, representing the two principal morphological forms of cushion plants, flat and hemispherical. The model achieved a mean average precision of 0.975 at IoU 0.5 and 0.785 at IoU 0.5–0.95, with only 7.65 M parameters. Field validation across four 100 × 100 m plots in the Bayi Glacier forefield confirmed its ability to map total cover (575.5–999.3 m²), patch density (0.14–1.48 ind/m²), and individual canopy metrics, revealing clear elevational gradients in species dominance and morphology. By automating extraction of ecological indicators directly from UAV imagery, CryoFlora provides a scalable tool for dynamic monitoring of glacier-forefield ecosystems, supporting conservation and adaptive management under accelerating climate change. Full article

Protecting groundwater against pollution from agricultural sources is a key aspect of sustainable management of soil and water resources. Implementation of sustainable strategies for agricultural production can be supported by modeling tools, which allow us to quantify the effects of different agricultural practices in the context of groundwater vulnerability to contamination. In this study we present a method to assess groundwater vulnerability to nitrate pollution based on a combination of the SWAT agro-hydrological model and the DRASTIC index method. SWAT modeling was applied to assess different scenarios of agricultural practices and identify solutions for sustainable management of soil and groundwater and reduction of nitrate pollution. The developed method was implemented for groundwater resources in a study area (Puck Bay region, southern Baltic coast), which represented a complex multi-aquifer system formed in Quaternary fluvioglacial deposits (sand and gravel) separated by moraine tills. In order to investigate the effects of different agricultural practices, 12 scenarios have been defined, which were grouped into four classes: crop type, fertilizer management, tillage, and grazing. An overlay index structure was applied, and ratings and weights to several factors were assigned. All analyses were processed using GIS tools, and the results are presented in the form of maps, which categorize groundwater vulnerability to nitrate pollution into five classes, ranging from very low to very high. The results reveal significant variability in groundwater vulnerability to nitrate pollution in the study area. Agricultural practices have a very strong influence on groundwater vulnerability by controlling both recharge rates and nitrogen losses from the soil profile. The most pronounced increases in vulnerability were associated with scenarios involving excessive fertilization and intensive grazing. Among crop types, potato cultivation appears to pose the greatest risk to groundwater quality. Full article

Groundwater–surface water interactions were investigated in the Highwood River (3952 km²) and Sheep River watersheds (1568 km²), originating in the Rocky Mountains headwaters of the South Saskatchewan River (Alberta, Canada), to improve understanding of hydrological processes that potentially influence water use and vulnerability to climatic change in representative, alpine-fed mixed-use watersheds. Similar to adjacent regions of the Bow, Red Deer and Oldman watersheds, the upper reaches of these watersheds are sparsely populated with significant seasonal glacier and snowmelt influence, while the lower watersheds are currently under increasing water supply pressure from competing agricultural–municipal interests, with notable risk of flooding during high-flow events and drought during the growing season. Investigations included mapping of hydrologic and hydrogeologic controls (aquifers, buried channels, colluvial deposits, etc.,) and synoptic geochemical and isotopic surveys (δ²H, δ¹⁸O, δ¹³C-DIC, ²²²Rn) to characterize evolution in water type and seasonal progression in streamflow sources and underlying mechanisms. Our findings confirm seasonal progression in streamflow water sources, characterized by a pronounced snowmelt-dominated spring freshet, but with a sustained recession fed by colluvial, moraine, fluvial, and fractured bedrock sources. Seasonal isotopic variations establish that shallow groundwater sources are actively maintained throughout the spring freshet, often accounting for a dominant portion of streamflow, which indicates active displacement of groundwater storage by snowmelt recharge during spring melt. The contrast in the proportion of alpine contributions in each watershed suggests these systems may respond very differently to climate change, which needs to be carefully considered in developing sustainable water-use strategies for each watershed. Full article

The small freshwater lakes of Spitsbergen remain poorly studied compared to surrounding marine ecosystems despite their sensitivity to rapid environmental changes. During the short ablation season, these shallow lakes exhibit physicochemical variability influenced by the harsh Arctic climate, local geology, and hydrology. This study analyzed six lakes located on marine terraces, moraine areas, and outwash plains in the Bellsund region to assess how physicochemical variability in their waters affects phytoplankton development. The lakes exhibited local and temporal variations in temperature, conductivity, ion composition, and nutrient levels, with generally low nutrient availability limiting biological productivity. Phytoplankton communities were quantitatively and qualitatively poor, dominated by green algae, either flagellates or mixed communities, including cyanobacteria. Green algae clearly dominated in lakes closest to the fjord shoreline, while dinoflagellates and cryptophytes dominated in inland lakes. Phytoplankton abundance and biomass were extremely low in one of the lakes situated on the raised marine terraces within the tundra vegetation zone (3 × 10³ ind L⁻¹ and 0.004 mg L⁻¹, respectively). In contrast, the much larger lake situated within the tundra zone nearer the fjord shoreline had values that were comparable to fertile lakes in the temperate zone (~30 thousand × 10³ ind L⁻¹ and ~28 mg L⁻¹, respectively). It should be noted that Monoraphidium contortum and Rhodomonas minuta dominated some of the lakes almost entirely. Phytoplankton abundance was related to physicochemical conditions: green algae increased with increasing ion concentrations (Cl⁻, Na⁺, K⁺, SO₄²⁻), P_min, Fe, and Mn; flagellates preferred colder waters with higher N_min and low TOC; cyanobacteria occurred in waters with lower COND, TOC, Ca²⁺, Si, Cu, and Zn. Phytoplankton biomass increased in July with increasing water temperature. Bird activity likely facilitated phytoplankton dispersal, increasing taxonomic diversity in frequently visited lakes. Full article

High-mountain regions such as the Ile-Alatau range of the Northern Tien Shan are highly sensitive to climatic fluctuations, where even minor variations in temperature and precipitation significantly influence glacier mass balance and hydrology. Despite this sensitivity, few long-term studies have examined the links between hydro-climatic trends, glacier retreat, and moraine lake development. This study investigates multi-decadal glacier and lake dynamics (1955–2024) in relation to observed climate variability, using an integrated hydro-climatic and remote-sensing approach. Temperature and precipitation records from four high-altitude meteorological stations were assessed using linear regression and the Mann–Kendall test, while glacier and lake extents were derived from aerial photographs and Landsat, Sentinel-2, and PlanetScope imagery across ten river basins. Results show statistically significant warming at all stations, with mean annual temperatures increasing by 0.14–0.28 °C per decade and summer temperatures by 0.15–0.30 °C, while precipitation remained stable or slightly decreased. Glacierized area decreased from approximately 269.6 km² in 1955 to 141.7 km² in 2021, representing a 47.4% reduction (≈−0.72% yr⁻¹) over six decades and underscoring the rapid regional cryospheric response to sustained climatic warming. Simultaneously, moraine-dammed lakes increased by 16–18% between 2017 and 2024. These trends highlight the dominant climatic control on glacier loss and lake evolution, emphasizing growing glacial lake outburst floods (GLOFs) and the need for adaptive water-resource management in Central Asia. Full article

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