污灌区土壤中重金属污染状况与磁化率的相关性分析

CORRELATION ANALYSIS OF HEAVY METAL POLLUTION AND MAGNETIC SUSCEPTIBILITY IN SOIL OF A SEWAGE IRRIGATION AREA

根据乌鲁木齐某典型石油化工废水灌溉区土壤样品重金属(Cr、Cu、Ni、Pb、Zn、As、Hg、Cd)总量结果,对其进行风险评价,并依据相关性分析结果,尝试用土壤磁化率指示污灌区重金属污染程度。结果表明:研究区土样中8种重金属含量均未超过GB 15681—2018《土壤环境质量农用地土壤污染风险管控标准(试行)》。除Pb以外,其余7种重金属含量均超出新疆农田土壤背景值,其中As、Hg和Cd超出背景值较多。内梅罗综合指数评价结果表明,土壤样品中除Pb以外,其余7种重金属均表现出不同程度的污染,其中Hg与Cd属于重度污染。地质累积指数评价结果表明,土壤样品中As、Hg和Cd的污染状况较重。相关性分析结果表明,该污灌区土壤磁化率与重金属含量之间存在一定程度的相关性,具有很好的指示作用。

To evaluate the pollution risk of heavy metals(Cr,Cu,Ni,Pb,Zn,As,Hg,Cd)in soil samples from typical petrochemical waste water irrigation areas in Urumqi.According to the results of correlation analysis,we tried to indicate the degree of heavy metal pollution with soil magnetic susceptibility.The results showed that the content of eight kinds of heavy metal in the soil samples did not exceed Soil Environmental Quality-Agricultural Land Soil Pollution Risk Management and Control Standard(Trial)(GB 15681—2018).Except Pb,the other seven kinds of heavy metal content exceeded the background values of Xinjiang farmland soil,especially for As,Hg and Cd.The evaluation results of the Nemero comprehensive index indicated that except for Pb,the other seven heavy metals in the soil samples showed different extents of pollution,and Hg and Cd were the most serious.While according to the geological accumulation index method,Hg,Cd and As were in serious pollution extent.Correlation analysis results showed that there was a certain degree of correlation between soil magnetic susceptibility and heavy metal content,which has a good indicating function.