金矿开采活动区土壤-农作物系统重金属污染特征及风险评价  

Heavy Metal Pollution Characteristics and Risk Assessment of Soil-crop System in Gold Mine Activity Area

作　　者：田志君 何付兵 姜昱聪 赵云峰 张涛 李佳颖 TIAN Zhi-jun;HE Fu-bing;JIANG Yu-cong;ZHAO Yun-feng;ZHANG Tao;LI Jia-ying(Beijing Institute of Mineral Geology,Beijing 101500,China;Beijing Institute of Geological Survey,Beijing 100195,China;Beijing Municipal Staff Innovation Studio(AFSM),Beijing 100195,China)

机构地区：[1]北京市矿产地质研究所,北京101500 [2]北京市地质调查研究所,北京100195 [3]北京市示范性职工创新工作室(活动断裂调查与监测),北京100195

出　　处：《环境科学》2024年第12期7218-7225,共8页Environmental Science

基　　金：北京市矿山地质环境监测系统运行维护项目(11000022T000000439565)。

摘　　要：基于土壤重金属Hg、Cd、Cr、Pb、As元素含量及七步形态组成和同位置农作物重金属含量,采用内梅罗综合污染指数法、富集系数法和风险评价编码法等开展土壤和农作物重金属污染特征及生态风险分析评价,探索重金属在土壤-农作物系统中的吸收富集规律,为研究区土壤污染防治及农作物食用安全提供科学依据.结果表明,研究区存在土壤重金属污染,Cd、Pb和As为主要污染元素,重度、中度和轻度污染等级占比分别为26.09%、4.35%和10.87%;各元素含量相较于环境治理前有所降低,但生态风险依然存在,元素Hg、Cr、Pb和As为低生态风险,元素Cd为高生态风险,是主要土壤生态风险因子;水果类、坚果类和谷物类农作物未受到污染,瓜果类、根茎类和叶菜类受到不同程度污染,重污染作物主要有小白菜、韭菜、萝卜和茄子,Cd和Pb元素是主要污染贡献因子;农作物重金属元素富集同金矿及其开采活动关系密切,农作物中Cd元素富集主要与土壤中Cd高可利用态有关,Pb元素富集主要与土壤中Pb高含量有关.平谷金矿开采区土壤重金属元素含量及其可利用态共同决定了农作物重金属元素富集,影响农作物重金属污染空间分布.由于农作物本身的生理特异性,在金矿开采活动区内,农作物种植类别也可形成重金属富集差异,大小表现为:叶菜类>瓜果类>根茎类>谷物类>水果类>坚果类.研究区现有农业种植条件下,瓜果类中的辣椒和茄子以及叶菜类的韭菜和小白菜等尚处于限制级种植品种.A contamination analysis was conducted on the soil and crops in the Liu Jia Dian gold mining area of the Pinggu District,Beijing,utilizing the contents and seven-step forms of heavy metals(Hg,Cd,Cr,Pb,and As)in soil and the heavy metal contents in crops at the same location.An assessment of ecological risk caused by heavy metal contamination in the soil and crops was carried out using the enrichment coefficient method and the risk assessment coding method.The study investigated the process of heavy metal absorption and enrichment in the soil-crop system,aiming to establish a scientific foundation for preventing and controlling soil pollution,as well as ensuring the safety of edible crops in the study area.Evidence indicated the presence of soil contamination by heavy metals in the study area,with Cd,Pb,and As being the primary pollutants.Moreover,the distribution of pollution levels could be categorized as severe,moderate,and mild,with proportions of 26.09%,4.35%,and 10.87%,respectively.The content of each heavy metal decreased following the implementation of environmental governance;however,the ecological risk remains present.Hg,Cr,Pb,and As posed minor ecological risks;however,Cd had a high ecological risk,making it the primary soil ecological risk factor.Fruits,nuts,and cereals in the Pinggu gold mining area remained uncontaminated.Various degrees of contamination were found in melons,rhizomes,and leafy vegetables.The Chinese cabbage,Chinese chive,radish,and eggplant were heavily contaminated,with Cd and Pb being the primary sources of contamination.The accumulation of heavy metals in crops was intricately linked to gold mines and their mining operations.The accumulation of Cd in crops was mainly influenced by the high availability of Cd in soil,whereas the accumulation of Pb was mainly influenced by the high concentration of Pb in the soil.The concentration of heavy metals in the soil and their bioavailability in the Pinggu gold mining area indicated the accumulation of metal elements in crops and impacted th

关 键 词：金矿 土壤重金属 农作物 生物富集系数(BCF) 平谷区 

分 类 号：X171.5[环境科学与工程—环境科学]