中国地质2024，Vol.51Issue(1)：276-289,14.DOI:10.12029/gc20220331001
长江下游干流沉积物重金属特征及生态风险评价
Characteristics and ecological risk assessment of sedimentary heavy metals from the Lower Mainstream of Yangtze River
摘要
Abstract
This paper is the result of hydrogeological survey engineering. [Objective]There are numerous water-intakes along the mainstream of the Yangtze River downstream,in order to ensure water safety and eco-environmental health,relevant situation of heavy metals in the nearshore sediment need to be studied urgently.[Methods]A total of 85 sediment samples were collected on both left and right banks from the upstream to the downstream with the investigation.Descriptive statistics analysis was used to show the characteristics of heavy metals.Correlational analysis and principal component analysis(PCA)were applied to study the sources of heavy metals.Geoaccumulation index and pollution load index were used to analyze the pollution levels,and the potential ecological risk of heavy metals were evaluated by the methods of potential ecological risk assessment index.[Results]The order of average content from high to low is Zn＞Cr＞Cu＞Ni＞Pb＞As＞Cd.From the upstream to the downstream,Cu、Zn、Cr、Ni had a small fluctuating but increasing trend,while As and Pb had a small fluctuating but decreasing trend,Cd showed decreasing trend with an obvious fluctuation.The most polluted one is Cd among seven heavy metals,which were mainly from human activities,such as agriculture.Cd accounted for 1.18%,1.18%,18.82%and 34.12%from polluted Class 1 to 4,respectively.Cr and Ni were non-pollution class,which mainly from industries and geochemical natural source.34.18%of all sampling sites were in moderate pollution(1≤PLIpoint＜2).RI was ranged from 19.48 to 388.62,and the proportions of slight potential ecological risk,medium potential ecological risk,strong potential ecological risk and extremely strong potential ecological risk were 38.82%,42.35%,17.65%and 1.18%,respectively.[Conclusions]Contents of all heavy metals in mainstream sediment of the Yangtze River downstream were at a lower level.The catchment were overall at non-pollution sate(PLI area＜1)with slight to moderate ecological risk.The average contents,pollution levels and potential ecological risks of heavy metals on the right bank were all higher than those on the left bank.关键词
重金属/来源/污染程度/生态风险/水文地质调查工程/长江下游Key words
heavy metal/source/pollution level/ecological risk/hydrogeological survey engineering/the Yangtze River downstream分类
资源环境引用本文复制引用
金阳,侯莉莉,齐秋菊,贾正阳,杨辉,姜月华,周权平,王晓龙,张鸿,梅世嘉,陈孜,杨海,吕劲松..长江下游干流沉积物重金属特征及生态风险评价[J].中国地质,2024,51(1):276-289,14.基金项目
中国地质调查局长江经济带地质资源环境综合调查工程(0531)、长江经济带地质资源环境综合评价项目(DD20190260)和长江经济带暨长三角一体化发展区资源环境承载能力监测评价项目(DD20221728)联合资助.Supported by the project of China Geological Survey"Comprehensive Geological Environment Survey Project of the Yangtze River Economic Belt"(No.0531),"Comprehensive Evaluation of Geological Resources and Environment of the Yangtze River Economic Belt"(No.DD20190260)and"Monitor and Evaluation of Resource Environmental Bear Capacity of the Yangtze River Economic Belt(Yangtze River Delta Integrated Development Zone)"(No.DD20221728). （0531）
