贵阳市城区土壤重金属累积现状研究

由于快速的城市化、工业化,城市土壤质量不断下降。越来越多的重金属在土壤中积累,会给城市居民的身体健康带来威胁。以贵阳市城区为研究区域,在三个城区采集50个土样,调查城区土壤重金属的累积状况并探究其来源。结果表明:城区土壤As、Cd、Cu、Ni、Pb和Zn的含量分别为16.8 mg kg-1、0.984 mg kg-1、66.1 mg kg-1、38.9 mg kg-1、79.5 mg kg-1、243 mg kg-1;三城区6种重金属分布特征总体上存在南明区>云岩区>小河区的趋势;南明区土壤重金属达到轻度污染,云岩和小河两区处于尚清洁状态,Pb和Zn为南明区土壤的主要污染元素,Cd是三城区土壤的主要污染元素;主成分分析和聚类分析显示Cd、Zn、Pb的可能主要来源是人为活动,As和Ni的来源是自然因素-成土母质,Cu的来源可能以人为活动为主。

The Status of Huoeavy Metals Accumulation in Soil of Guiyang City

With urbanization and industrialization increasing quickly,the quality of urban soil is gradually declining.More and more heavy metals have accumulated in soil and this will pose a threat to urban residents’ health.For the study area in Guiyang,a survey was conducted to study the accumulation of soil heavy metals and explore their sources based on 50 soil samples of three functional study area in Guiyang city.The results showed that concentrations of soil As,Cd,Cu,Ni,Pb,Zn were 16.8 mg kg-1,1.0 mg kg-1,66.1 mg kg-1,38.9 mg kg-1,79.5 mg kg-1,243.0 mg kg-1,respectively.On the whole,the distribution characteristics of soil heavy metals in Guiyang city were that the highest was in Nanming district,followed by Yunyan district and Xiaohe district.There was a light pollution of soil heavy metals in Nanming district,while the other two districts were in a clean state.The main pollution elements were Pb and Zn in Nanming district,and Cd was the main pollution element in all these three districts.Principal component analysis and cluster analysis showed that the probable sources of Cd,Zn and Pb were derived from human activities,and natural factors(soil parent materials) caused the As and Ni pollution,and the source of Cu might be contributed to human activities which could not be determined by the study.