RESUMO
Snow cover is a key element in the water cycle, global heat balance and in the condition of glaciers. Characterised by high temporal and spatial variability, it is subject to short- and long-term changes in climatic conditions. This paper presents a unique dataset of snow measurements on Hansbreen, an Arctic glacier in Svalbard. The dataset includes 79 archived snow profiles performed from 1989 to 2021. It presents all available observations of physical properties for snow cover, such as grain shape and size, hardness, wetness, temperature and density, supplemented with organised metadata. All data has been revised and unified with current protocols and the present International Classification for Seasonal Snow on the Ground, allowing comparison of data from different periods and locations. The information included is essential for estimations of glacier mass balance or snow depth using indirect methods, such as ground-penetrating radar. A wide range of input data makes this dataset valuable to the greater community involved in the study of snow cover evolution and modelling related to glaciology, ecology and hydrology of glacierised areas.
RESUMO
Melting glaciers release new ground surfaces, which may be either a source of greenhouse gas emissions or a sink for carbon dioxide. Studies carried out in subpolar and alpine ecosystems confirm the relatively rapid soil development and increase of carbon and nitrogen pools. However, observations from high-mountain glacier forelands in cold and dry climate are very scarce. This study analyses the impact of major environmental factors related to climate, topography, and vegetation, over a time-scale, on soil development and spatial soil differentiation in the foreland of Uisu Glacier, East Pamir Mountains. Moreover, the usefulness of the World Reference Base (WRB) and Soil Taxonomy in the classification of poorly developed soils in the ultracontinental climate was assessed. Geomorphological, pedological, and botanical surveys covered a sequence of terraces, alluvial fans, and end-moraines. Typical characteristics of the soils in the glacier foreland were: very high stoniness, coarse texture, high content of calcium carbonate, alkaline reaction, and low salinity. Soil development has extremely low intensity and was manifested in (a) soil organic carbon pools being among the lowest reported in the world (up to 1.4 kg m-2 in the layer 0-50 cm), and (b) the presence of cambic/calcic horizons only on landforms older than of Mid-Holocene age (estimated). It was concluded that both the extremely cold and extremely dry climate conditions in the Uisu Glacier foreland limit the water flux and availability, suppress vegetation density and variability, and slow down the rate of soil development. Both WRB and Soil Taxonomy were able to reflect the advances in soil development and spatial soil differentiation (Calcaric Hyperskeletic Leptosols - Calcaric Cambisols - Cambic Calcisols, and Gelifluvents - Haplocambids - Haplocalcids, respectively); however, highlighting different features developed under an extremely cold and dry climate conditions of the East Pamir Mountains.
