塔里木河流域东部大气降水化学特征及来源解析OA

This study collected a total of 128 atmospheric precipitation samples along a north-south gradient in the eastern Tarim River Basin(Bayingolin Mongol Autonomous Prefecture)during 2021-2022,and systematical-ly analyzed their chemical composition characteristics and ion sources using multiple analytical methods.The re-sults show that the precipitation in the eastern Tarim River Basin is generally near neutral,with no strongly acidic rain,although some samples had pH values ranging from 6.62 to 6.99 and EC values ranging from 158.84 to 383.17 μS·cm-1.Ion concentrations exhibited a spatial pattern of'higher in the south and lower in the north'and showed seasonal characteristics of higher values in spring and winter and lower values in summer and autumn.Ca2+and SO2-4 were the dominant ions,with average concentrations of 1401.20 μeq·L-1 and 516.21 μeq·L-1,re-spectively.The SO2-4/NO-3 ratio indicated overall mixed pollution.Source analysis revealed that Na+and Cl-mainly originated from inland saline soil wind erosion;Mg2+and Ca2+were primarily from terrestrial sources;while NH+4,SO2-4,and NO-3 were mainly influenced by human activities.The PMF model quantitatively indicat-ed that the contributions of six major sources were as follows:secondary inorganic aerosols(28.41％),evaporite/salt soil weathering(26.81％),dust(21.46％),biomass burning(9.83％),industrial emissions(8.32％),and agricul-tural sources(5.17％).This study enriched the precipitation chemistry database of arid regions in China and pro-vided a scientific basis for regional air pollution prevention and control.