浙江省金华市农用地重金属污染及安全利用分区

On evaluation and safe utilization subregion of heavy metal polluted agricultural land in Jinhua

为全面了解金华市农用地土壤重金属的污染状况,提升土地资源的配置效率,利用描述性统计和地统计分析等方法研究金华市农用地土壤重金属含量特征,并结合单因子指数法、内梅罗综合指数法和潜在生态危害指数法开展土壤重金属污染评价,进而对金华市农用地安全利用进行分区,提出针对性安全利用调控策略.结果表明:1)研究区土壤重金属含量空间分布较为集中,呈现西北部高、中部和东南部较低的特点.2)单项污染指数结果表明,研究区土壤中镉污染最为严重,污染点位占比为13.86%,铜污染次之,占比为1.29%;内梅罗综合污染指数结果显示,研究区土壤以清洁水平为主,清洁点位占比为79.81%,部分地区存在中度、重度污染;潜在生态危害指数结果显示,研究区土壤主要为低风险和中风险,低中风险点位总占比为94.42%,不存在高风险地区.3)研究区安全利用分区结果显示,各类区域占地面积由大到小依次为风险监控区、清洁安全区、风险预警区、基本清洁区、严格管制区.

In order to comprehensively understand the pollution status of heavy metals in farmland soil of Jinhua City and improve the allocation efficiency of land resources,the content characteristics of heavy metals in farmland soil of Jinhua City were studied by using descriptive statistics and geostatistical analysis,the single factor index method,Nemerow comprehensive index method and potential ecological hazard index method were combined to carry out soil heavy metal pollution assessment.The safe use of agricultural land in Jinhua City was divided into different zones,and the corresponding control strategies were put forward.The results showed that:1)the spatial distribution of soil heavy metal content in the study area was relatively concentrated,which was higher in the northwest,and lower in the middle and southeast.2)the results of single pollution index showed that cadmium pollution was the most serious,accounting for 13.86%,followed by copper pollution,accounting for 1.29%;The results of Nemero comprehensive pollution index showed that the soil in the study area was mainly clean,and the proportion of clean sites was 79.81%.There were moderate and severe pollution in some areas;The results of potential ecological hazard index showed that the soil in the study area was mainly low-risk and medium risk,and the total proportion of low and medium risk sites was 94.42%.There was no high-risk area.3)according to the results of the study area,the order of the area from large to small was risk monitoring area,clean safety area,risk warning area,basic clean area,strict control area.