Geochemistry of cryoconite and soils in the Central Caucasus region and its environmental implications  

作　　者：Ivan KUSHNOV Evgeny ABAKUMOV Rustam TEMBOTOV Vyacheslav POLYAKOV 

机构地区：[1]Saint Petersburg State University,7/9 University Embankment,St Petersburg 199034,Russian Federation [2]Tembotov Institute of Ecology of Mountain Territories,Russian Academy of Sciences,37-a I.Armand Str.,Nalchik,360051,Russian Federation

出　　处：《Journal of Mountain Science》2021年第12期3109-3124,共16页山地科学学报（英文）

基　　金：This work is supported by the Russian Foundation for Basic Research,project No.19-05-50107;Saint Petersburg State University grant for research equipment upgrades No.1.40.541.2017.

摘　　要：Climate change and deglaciation are active processes in current changing environments.In the Central Caucasus region rapid degradation of glaciers is caused often by the formation of superficial blackcolored sediments-cryoconite.Cryoconite plays a crucial role in changing ecosystems and may contribute to the formation of primary soils after glacier retreat.Over the past 20 years,the frequency of mudflows and other dangerous mountain events have increased in the Central Caucasus,which is associated with the glacial retreats.Intensification of tourism results in increasing of traffic,recreational activity and environment contamination.Determination of the cryoconites geochemical properties in comparison with other types of sediments and local soils is crucial for investigation of geochemistry and contamination state of superficial glacial sediments.This environmental aspect is important in terms of the Central Caucasus settlements safety under conditions of deglaciation and anthropogenic influence.The sediments studied(cryoconite,mudflow,moraine)were sampled at Garabashi and Skhelda glaciers as well as some local soils at the Baksan gorge.Sampled materials were investigated in terms of physicochemical and agrochemical parameters.The concentrations of trace elements(Cu,Pb,Zn,Ni,Cd)were also determined and contamination indices(geoaccumulation index-Igeo,contamination factor-CF and degree of contamination-Cdegree)were used to evaluate the pollution status of studied material.Data obtained shows much higher content of organic carbon in soils(up to 7.82%)in comparison with cryoconite(max.1.63%)due to presence of vegetation,however,the basal respiration values in some cases were similar betweenсryoconite and soils,indicating high rates of microbial activity in a cryoconite holes.It was found that almost all materials studied have sandy structure.Cryoconite sediments on both of the glaciers are enriched with phosphorus,high values of K_(2)O(max.298 mg·kg^(-1))and N-NH4(max.247 mg·kg^(-1))are identified at Garabashi gl

关 键 词：Cryoconite Trace elements ENTISOLS CONTAMINATION Central Caucasus 

分 类 号：P343.6[天文地球—水文科学] P59[天文地球—地球物理学]