土壤重金属污染调查与评估的误区及其改进方法

Error and its Improvement of Soil Heavy Metal Pollution Survey and Evaluation

我国目前对土壤重金属污染调查与评估的方法是分析土壤重金属全量,并对照《GB15618-1995土壤环境质量标准》,得到超标比例和超标倍数等评估结论,不能反映土壤重金属对食品安全和饮用水安全的威胁程度。滇池东岸土壤的研究在分析重金属全量的基础上,通过对土壤中重金属的交换态、碳酸盐结合态(碳酸态)、铁锰氧化物结合态(铁锰态)、有机质硫化态(有机态)、残渣态等分析,评估土壤重金属全量中对农业生产和饮用水水源有威胁的速效态和有效态元素含量,结果显示:研究区土壤中Cu、Zn、Ni安全,Pb、Cd不安全。有针对性地提出环境保护措施,能有效指导农业生产和饮用水水源管理工作。

Theinvestigation and evaluationmethod of soil heavy metal pollution in our country at present is to detect the content of heavy metal and compare the results with the soil environment quality standard ( GB15618 -1995 ) and calculate the ratio of the excessive proportion and excess ratio. This method could not reflect the degree of the threat of soil heavy metal to food safety and the safety of drinking water. On the basis of the study on the analysis of the full content of heavy metals, the exchange state, carbonate state of heavy metals in soil ( carbonate) , iron, manganese oxide combination state ( Fe^ Mn) , organic sulfide ( organic) , residue analysis, evaluation of soil heavy metal quantity threating to agricultural production and drinking water sources in the available state and effective state element content were tested. Environmental protection measures were put forward accordingly,which would effectively guide the safe agricultural production and drinking water management.