基于GIS的杭州市居民区土壤重金属污染现状及空间分异研究

研究了杭州市50个代表性居民小区土壤重金属(Cd、Cr、Cu、Ni、Pb和Zn)的含量,按照国家《土壤环境质量标准》对该市居民区土壤重金属污染状况做出了评价,并在GIS技术支持下,研究了土壤重金属污染的空间变异性。结果表明,杭州市居民区土壤均受到了不同程度的污染。其中4%的土壤轻度污染,54%的土壤中度污染,42%的土壤严重污染。土壤重金属污染具有显著的空间分异特征,严重污染区域大致呈西北-东南走向,包括了城北的大部分地区、市中心和城东南一些地区。工业生产和居民区形成时间对居民区土壤重金属积累有较大的影响。

GIS-Assisted Assessment and Spatial Variation of Heavy Metal Pollution in Soils of Residential Areas of Hangzhou City

The objective of this study was to assess spatial variation of heavy metal pollution in the soils of residential areas of Hangzhou city. Fifty soil samples were collected respectively from fifty residential areas in Hangzhou city to analyze heavy metals, including Cd,Cr,Cu,Ni,Pb and Zn. The heavy metal pollution of the soils was assessed using single pollution index and comprehensive pollution index methods on the base of the Chinese Soil Environment Quality Standard. In addition,a database of heavy metal concentrations was established with the support of GIS to analyze spatial variation of the pollution. A spatial distribution map of the heavy metal pollution was attained. The results showed that all the soils had been contaminated by heavy metals to a different extent. About 4% of the residential soils were low-level polluted, and 54% were medium-level polluted, and the rest were high-level polluted. The high-level polluted soils were mainly distributed in the northwest-southeast orienting areas of the city which included most of the north, center regions and part of the southeast regions of the city. Industrial activities and age of the residential areas were the most important factors affecting accumulation of heavy metals in the soils.