北京市东南郊灌区土壤和农产品重金属含量水平评估

Contamination Risk Assessment of Heavy Metal in Soils and Crops of the Irrigation District in the Southeastern Suburbs of Beijing

为明确北京东南郊典型灌区土壤和作物重金属含量和污染水平,2015年对该灌区31个监测点位土壤样品和62个作物样品的6种重金属进行了检测,利用单因子污染指数法、综合污染指数法和综合潜在生态风险评估法对土壤污染状况和生态风险进行了评估,利用皮尔逊相关分析、主成分分析和地统计学分析对土壤重金属来源进行了分析。研究结果表明灌区土壤重金属含量属于安全级别,潜在生态风险较低,农产品重金属含量满足国家食品标准,灌区土壤重金属的主要来源是农业施肥、污水灌溉和大气沉降。

In order to analyze the concentration and pollution characteristics of heavy metals in top soil and agricultural products in irrigation district at the Southeastern irrigation district in Beijing,As,Cr,Cu,Hg,Pb,and Zn in 62 topsoil samples and 62 crops samples were collected from 31 sites in the irrigation district and tested in 2015.The single polluted index,comprehensive polluted index,and comprehensive potential ecological index were used to analyze the pollution levels and potential ecological risk of soil.Pearson correlation coefficient,principal component analysis,and geo-statistical analysis were used to analyze the sources of heavy metal in soil.The results show the soil was not contaminated by heavy metals,the potential ecological risk was low,and the concentrations of heavy metals in agricultural products can meet the requirements of corresponding standard.Utilization of fertilizer,sewage irrigation,and atmospheric deposition were the main sources of heavy metals in soil.