重庆市秀山县北部大气干湿沉降重金属元素分布特征及来源分析  

Distribution characteristics and source analysis of heavy metals from dry and wet atmospheric deposition in northern Xiushan County,Chongqing

作　　者：蔡柯柯 赵志强 蒙丽 王孝萌 刘键 罗仁凤 CAI Ke-Ke;ZHAO Zhi-Qiang;MENG Li;WANG Xiao-Meng;LIU Jian;LUO Ren-Feng(Chongqing Geological and Mineral Resource Exploration and Development Bureau 607 Geological Team,Chongqing400054,China;Chongqing Institute of Geology and Mineral Resources,Chongqing401120,China;College of Environment and Ecology,Chongqing University,Chongqing400044,China)

机构地区：[1]重庆市地质矿产勘查开发局607地质队,重庆400054 [2]重庆地质矿产研究院,重庆401120 [3]重庆大学环境与生态学院,重庆400044

出　　处：《物探与化探》2024年第1期237-244,共8页Geophysical and Geochemical Exploration

基　　金：重庆市规划和自然资源局项目“重庆1∶5万石堤幅、溶溪幅、龙池幅、花垣幅、秀山幅、石耶幅6幅土地质量地质调查”(渝规资[2020]188号)。

摘　　要：为了解秀山北部大气干湿沉降物中重金属含量情况,使该区环境污染防治和农田土壤安全利用更具针对性,2019年4月~2020年4月,连续接收秀山县北部18个样点大气干湿沉降物,并分析测试其中Cd、Cr、Cu、Ni、Pb、Zn、Hg等7种重金属元素的含量;结合地形、地貌特点,分析秀山县北部大气干湿沉降中重金属的分布规律及来源,并采用地累积指数法评估大气干湿沉降中重金属对土壤的污染状况。结果表明:除Hg外,6种重金属元素存在明显的分区性,沉降高值区集中分布在川河盖两翼及东部,该区域大气干湿沉降物中6种重金属含量远高于全国及重庆市平均值;其余一般沉降区6种元素沉降通量均小于全国均值25%百分位。川河盖两翼较高的大气干湿沉降通量受东部花垣县铅锌矿开采及特殊地形地貌的综合影响,陡增的地形使得沉降中7种重金属通量增加了49倍,应加强该类型地貌区环境安全的监测与评估工作。经地累积指数法评估,川河盖两翼大气干湿沉降重金属中Cd为中度污染—严重至极度污染,Pb为轻度污染—中度污染,Zn为轻度污染—中度至严重污染。This study aims to determine the contents of heavy metals from dry and wet atmospheric deposition in northern Xiushan County for targeted environmental pollution prevention and control and safe farmland soil utilization.Based on the dry and wet atmos-pheric deposition samples continuously received from 18 sampling sites in northern Xiushan County from November 2019 to November 2020,this study tested the contents of seven heavy metal elements,including Cd,Cr,Cu,Ni,Pb,Zn,and Hg.Considering the top-ographic features,this study analyzed the distribution patterns and sources of heavy metals from dry and wet atmospheric deposition in northern Xiushan County.Moreover,this study assessed the soil pollution caused by heavy metals from dry and wet atmospheric deposi-tion using the geoaccumulation index method.The results show that except Hg,the other six heavy metal elements exhibited significant zoning,with their high-value deposition areas distributed primarily in the flanks and eastern segment of Chuanhegai,where their con-tents were much higher than the national and Chongqing's averages.In contrast,their depositional fluxes in other general deposition ar-eas were less than the national averages by 25%.The high dry and wet atmospheric deposition in the flanks of Chuanhegai was subjec-ted to both the mining of the lead-zinc deposit in Huayuan County in the east and the special topography.The abrupt topography in-creased the fluxes of the seven heavy metals in the dry and wet atmospheric deposition by 49 times.Therefore,the monitoring and as-sessment of environmental safety in this type of landform area should be strengthened.According to the assessment results of the geoac-cumulation index method,the flanks of Chuanhegai were moderately-severely to extremely polluted by Cd,slightly-moderately polluted by Pb,and slightly-moderately to severely polluted by Zn.

关 键 词：大气干湿沉降 重金属 来源分析 秀山 

分 类 号：X142[环境科学与工程—环境科学]