Deng Jiancai, Wang Yuansheng, Liu Xin, Hu Weiping, Zhu Jinge, Zhu Lin
State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73# East Beijing Road, Nanjing City, Jiangsu Province, 210008, China.
Jiangsu Taihu Planning and Design Institute of Water Resource Co., Ltd., Suzhou, China.
Environ Monit Assess. 2016 May;188(5):296. doi: 10.1007/s10661-016-5301-8. Epub 2016 Apr 18.
The concentrations and spatial distributions of eight heavy metals in surface sediments and sediment core samples from a shallow lake in China were investigated to evaluate the extent of the contamination and potential ecological risks. The results showed that the heavy metal concentrations were higher in the northern and southwestern lake zones than those in the other lake zones, with lower levels of As, Hg, Zn, Cu, Pb, Cr, and Ni primarily observed in the central and eastern lake regions and Cd primarily confined to areas surrounding the lake. The concentrations of the eight heavy metals in the sediment profiles tended to decrease with increasing sediment depth. The contents of Ni, Cu, Zn, Pb, and Cd in the surface sediment were approximately 1.23-18.41-fold higher than their background values (BVs), whereas the contents of Cr, As, and Hg were nearly identical to their BVs. The calculated pollution load index (PLI) suggested that the surface sediments of this lake were heavily polluted by these heavy metals and indicated that Cd was a predominant contamination factor. The comprehensive potential ecological risk index (PERI) in the surface sediments ranged from 99.2 to 2882.1, with an average of 606.1. Cd contributed 78.7 % to the PERI, and Hg contributed 8.4 %. Multivariate statistical analyses revealed that the surface sediment pollution with heavy metals mainly originated from industrial wastewater discharged by rivers located in the western and northwestern portion of the lake.
对中国某浅水湖泊表层沉积物和沉积岩芯样品中8种重金属的浓度及空间分布进行了调查，以评估污染程度和潜在生态风险。结果表明，湖泊北部和西南部区域的重金属浓度高于其他湖区，中部和东部湖区主要观测到较低水平的砷、汞、锌、铜、铅、铬和镍，镉主要集中在湖泊周边区域。沉积物剖面中8种重金属的浓度随沉积物深度增加而降低。表层沉积物中镍、铜、锌、铅和镉的含量比其背景值高出约1.23 - 18.41倍，而铬、砷和汞的含量与背景值几乎相同。计算得出的污染负荷指数（PLI）表明，该湖泊表层沉积物受到这些重金属的严重污染，且镉是主要污染因子。表层沉积物的综合潜在生态风险指数（PERI）在99.2至2882.1之间，平均为606.1。镉对PERI的贡献率为78.7%，汞为8.4%。多元统计分析表明，表层沉积物重金属污染主要源于湖泊西部和西北部河流排放的工业废水。
