Geochemical Characteristics And Spatial Heterogeneity Of Soil Elements In The Yili River Basin

Soil is in an important position in the ecosystem because it is the place where minerals,water,air and organisms react.This paper takes the soil elements of the Yili River Basin as the research object,and uses the classical statistical and geostatistical methods to analyze the geochemical characteristics and spatial differences of 15 elements,TOC,carbonate,and magnetic susceptibility of 40 soil sample collection points in the study area Relevant research was carried out qualitatively;the current pollution assessment of 13 elements in the study area was carried out using Nemero ’s comprehensive pollution index method and geoaccumulation index.The main conclusions were as follows:(1)The variation coefficients of soil elements in the study area from large to small are: χfd > χlf = P > Sr > carbonate > TOC > Cu > Ca > Mg > Zn > V > Pb > Mn > Ba =Fe >Ti > K > Na > Al,the elements all have weak variation;compared with the background values of Xinjiang soil elements,the contents of Ca,Al,Fe,K,Ti,P,Ba,V,Zn exceed the background values of Xinjiang soil,and the average contents of the other6 elements are low Background value.(2)Through correlation analysis,principal component analysis and cluster analysis: 15 elements in the Yili River Basin can be classified into 4 categories,and the spatial distribution pattern is determined by different impact factors.Al,Fe,Mn,Ti,V,Cu,Zn are mainly affected by natural factors such as geological conditions;Ca,Sr are mainly affected by natural factors;Mg,P are mainly affected by natural factors such as precipitation;Ba,K,Pb are mainly affected by Influence of natural factors such as temperature climate.(3)By analyzing the spatial distribution characteristics of 15 elements and TOC,carbonate,and magnetic susceptibility of soil in the study area,it is concluded that the high-value areas of Kriging spatial distribution characteristics of Al,Cu,Mn,V,Fe,Ti are mainly located in Xinyuan County,In Nilek County,the spatial distribution characteristics are mainly affected by natural factors such as geological conditions.The high-value areas of the Kriging spatial distribution characteristics of Ca,Mg,and Sr are mainly located in Huocheng County,Yining City,Qapqal County,and Xinyuan County.The spatial distribution is mainly affected by natural factors and human factors.The Kriging spatial distribution features of K,Zn,and Pb are mainly located in Gongliu County and Nileke County.The spatial distribution features are mainly affected by natural factors such as temperature and climate,and human activities such as coal chemical industry.The impact is more prominent.The high-value areas of the Kriging spatial distribution characteristics of Ba and Na elements are mainly located in Huocheng County,Qapqal County,Yining City and Yining County.The spatial distribution is mainly affected by natural factors and human factors.The Kriging spatial distribution characteristics of TOC and P elements are mainly in Nileke County.The distribution characteristics are mainly influenced by natural factors such as precipitation and human activities such as fertilization,farming measures,and planting.The artificial factors are more prominent.(4)The geochemical baseline is an important reference for distinguishing between natural environment and human activities.In this paper,standardized methods are selected and Fe is used as the standard element to establish geochemical baseline values for 13 heavy metal elements such as Mn,V,Zn,and Mg.Only Mg,Mn,Sr,Cu and Pb are slightly smaller than the Xinjiang soil background values;the geochemical baseline values of 13 heavy metal elements are used as the background values of the watershed to reflect the heavy metal pollution.The results show that: Al,Mg,Ti,Mn,Ba,Sr,The 10 elements V,Zn,Cu and Pb are not polluted and are in a clean state.