Assessment on environmental quality of heavy metals in agricultural soils of Chongming Island, Shanghai City
Assessment on environmental quality of heavy metals in agricultural soils of Chongming Island, Shanghai City
复制标题
DOI：
10.1007/s11442-010-0135-8
复制
发表时间：
2010-02
影响因子：
4.9
通讯作者：
Chao Sun;C. Bi;Zhenlou Chen;Dongqi Wang;Cui Zhang;Yuedi Sun;Zhongjie Yu;Dong Zhou
中科院分区：
文献类型：
--
作者：
Chao Sun;C. Bi;Zhenlou Chen;Dongqi Wang;Cui Zhang;Yuedi Sun;Zhongjie Yu;Dong Zhou
在大规模调查的基础上，采用国家、地方和行业标准对崇明岛农业表层土壤重金属（Pb、Cd、Cr、As、Hg）的环境质量进行了评价。结果表明，重金属Pb、Cd、Cr、As和Hg的平均含量分别为21.6mg·kg-2、0.176mg·kg-2、69.4mg·kg-2、9.209mg·kg-2和0.128mg·kg-2。与上海市土壤背景值相比，崇明岛农业表层土壤中除Pb和Cr外，其余重金属平均含量均超过相应的自然背景值。Cd、As和Hg的含量分别比上海市背景值高33.0%、1.2%和26.3%。此外，还利用地理信息系统的反距离插值（IDW）工具研究了重金属的空间变异。结果表明，大部分农用土壤质量良好，生态土壤、良好土壤、合格土壤和不合格土壤的比例分别为1.26%、97.1%、1.47%和0.12%。土壤中Pb、Cd、Cr、As和Hg超标率分别为10.1%、85.7%、27.0%、55.4%和55.2%。在这三种土地利用类型的土壤中，菜地土壤重金属污染最为严重，这可能与农药的过量使用有关。Pb、Cd、As和Hg的年沉降通量分别为7736 μg·m−2·a−2、208 μg·m−2·a−2、2238 μg·m−2·a− 2和52.8 μg·m−2·a−2。农作物秸秆焚烧是大气沉降中重金属的重要来源，大气沉降对崇明岛农业土壤中重金属的贡献较大。
The environmental quality of heavy metals (Pb, Cd, Cr, As, Hg) in agricultural surface soil of Chongming Island was assessed by national, local and professional standards based on a large scale investigation, in which 28 samples from vegetable plots, 65 samples from paddy fields and 9 samples from watermelon fields were collected from whole island area. Results showed that the average concentration of Pb, Cd, Cr, As and Hg was 21.6 mg·kg−2, 0.176 mg·kg−2, 69.4 mg·kg−2, 9.209 mg·kg−2and 0.128 mg·kg−2, respectively. Compared with the background value of Shanghai City soil, except for Pb and Cr, all the other heavy metals average concentrations in Chongming Island agricultural surface soil exceeded their corresponding natural-background values. The concentrations of Cd, As and Hg were 33.0%, 1.2% and 26.3% higher than the background value of Shanghai City, respectively. In addition, inverse distance interpolation (IDW) tool of GIS was also applied to study the spatial variation of heavy metals. The results indicated that most of agricultural soil quality was good, and the ratio of ecological, good soil, certified soil and disqualified soil were 1.26%, 97.1%, 1.47% and 0.12%, respectively. About 10.1%, 85.7%, 27.0%, 55.4% and 55.2% soil samples exceeded the Pb, Cd, Cr, As and Hg background value of Shanghai City, respectively. Among these three land use type soils, vegetable soil was most seriously polluted by heavy metals, which is probably related to the over-application of pesticides. The annual deposition fluxes of Pb, Cd, As and Hg were 7736 μg·m−2·a−2, 208 μg·m−2·a−2, 2238 μg·m−2·a−2and 52.8 μg·m−2·a−2, respectively. Crop straw burning was the important source of heavy metals of atmospheric deposition, and atmospheric deposition contributed a lot to heavy metals in agricultural soil in Chongming Island.