摘要
通过对小江流域消落带土壤重金属分布特征和评价分析,结果表明,重金属Cr、Cu、Zn、Pb、Cd、Ni含量均值分别为23.76mgkg-1、20.78mgkg-1、82.92mgkg-1、36.84mgkg-1、0.064mgkg-1、38.08mgkg-1,均未超过国家土壤环境质量标准(GB15618-1995),其中Zn、Pb、Ni均高于重庆市土壤背景值。Cr与Cd、Cu与Zn、Cu与Cd,Cu与Ni的相关系数分别为0.9077、0.7969、0.4217、0.4347,呈正相关性。但其他元素间相关性不显著。Ni是本区表层土壤重金属污染的主要因子,重金属元素的污染程度依次为Ni>Zn>Cu>Cd>Pb>Cr。土壤重金属单项污染指数均值小于0.7,综合污染指数为0.47,总体上,污染水平为清洁,土壤重金属潜在生态风险为轻度生态危害。不同功能区潜在生态危害程度上以三中最大,其次为中原和铺溪,产生潜在生态危害的主要重金属是Cd、Pb,Cu、Cr次之。
Distribution characteristics of soil heavy me tals in water-level-fluctuating zone in Xiaojiang River were investigated and analyzed.The results showed that contents of the heavy metals were 23.76 mg kg^-1,20.78 mg kg^-1,82.92 mg kg^-1,36.84 mg kg^-1,0.064 mg kg^-1 and 38.08 mg kg^-1,respectively.The results of statistical analysis indicated that concentrations of the heavy metals detected in the studied soils did not exceed the National Standard for Soil Environment Quality （GB15618-1995）.Zn,Pb,Ni were higher than background values of Chongqing soil.Correlation coefficients of Cr-Cd,Cu-Zn,Cu-Cd and Cu-Ni were 0.9077,0.7969,0.4217 and 0.4347,respectively.There were positive correlations among with them,but not significantly with others.Ni was considered as a dominant element causing soil heavy metal pollution in the area.the order of typical heavy metal pollution extent was NiZnCuCdPbCr.the mean value of single-factor indices of soil heavy metals in all soil samples was less than 0.7.Comprehensive pollution index of soil heavy metal was 0.470,the level of pollution was cleaner.The potentially ecological risk of heavy metal was also light as the mean integrated index was low.The levels of potential ecological hazard for soils in different functional zones were subsequently decreased from Shanzhong,Zhongyuan and Puxi.Pb and Cd brought the dominating potential ecological hazard,followed by Cu and Cr.
出处
《土壤通报》
CAS
CSCD
北大核心
2010年第1期206-211,共6页
Chinese Journal of Soil Science
基金
重庆市发展改革委员会和重庆市科学技术委员会专项基金项目(03-26)资助
关键词
土壤重金属
分布特征
潜在生态风险评价
小江流域
Soil heavy metal Distribution characteristics Potential ecological risk assessment Xiaojiang River
