Environmental Characteristics Recorded In The Sediments Of The Ny-Ålesund Glacier In The Arcti

Knowledge of the past is the key to the future.To accurately assess the specific historical status of the current environment and its future trends,it is first necessary to understand the patterns and evolutionary mechanisms of past climate and environmental change,and sediments are the best object of study.Since the 20th century,changes in the geochemical properties of continuous sediments such as lakes,loess,paleosols and marine sediments have been considered an important indicator of environmental change.As an important component of the global dust system,glacial sediments can indicate changes in global climate,aerosol sources,ocean elements and productivity.The international community is expressing increasing concern about climate change in the 21st century,and global warming is most evident in the Arctic region.The study reveals the climate change since the Little Ice Age in the Ny-?lesund region of the Arctic,and also analyzes the global and regional differences in environmental change by making regional comparisons with mountain glaciers on the eastern edge of the Tibetan Plateau and other glaciers around the world.As global warming continues to intensify,the shrinking ice caps and retreating glaciers at high latitudes have raised concerns.To understand the response of glacial to environment and climate in modern high-latitude ice-marginal environments,this paper investigated glacial sediments in the Ny-?lesund region of the Arctic and clarified the response of polar environmental to global changes through geochemical characteristics of glacial sediments.The results showed that:（1）main factors affecting the elements distribution of the Ny-?lesund glacial sediments were thought as soil formation（42.46%）,bedrock and weathering（28.68%）,and biological activity（10.16%）;Variations of Si O₂/Al₂O₃、Si O₂/Al₂O₃+Fe₂O₃ and Na₂O/K₂O,indicating low weathering of the soil.The ratio of Na₂O/K₂O was negatively correlated to the CIA with the average CIA of Ny-?lesund glacial sediments 50.13,which implied glacial sediments at the early stage of chemical weathering and depletion of Ca and Na;（2）the Ny-?lesund glacial sediments and stone circle for main minerals of quartz,feldspar,and muscovite as well as dolomite and calcite.Heat conduction and frost erosion are the main reasons for the formation of stone circle.The degree of weathering of the stone circle is low in cold and dry climatic environments.The main minerals at the edge of the stone circle are albite and quartz,and the low content of albite leads to the inapplicability of Na₂O/K₂O to explain the degree of weathering of the stone circle.（3）changes of carbonate content in sediments with glacier front retreating in different period implied that weathering rate of calcite averagely reached an estimate of 0.0792%wt/year in glacier A.The succession of vegetation made biological weathering become an important driving force for carbonate leaching from glacial sediments.