三峡库区淹没区土壤重金属形态分布及其对水质影响  

Chemical Fraction Composition Characteristics of Heavy Metals and Effects on Water Quality in Submerged Soil of Three Gorges Reservoir Area

作　　者：王图锦[1] 胡学斌[1] 吉芳英[1] 何强[1] 叶姜瑜[1] 黎司[1] 曹琳[1] 

机构地区：[1]重庆大学三峡库区生态环境教育部重点实验室,重庆400045

出　　处：《环境科学研究》2010年第2期158-164,共7页Research of Environmental Sciences

基　　金：科学技术部国际合作项目(2007DFA90660);教育部科技创新工程重大项目培育资金项目(708071)

摘　　要：结合三峡水库调度模式,在汛期及汛后对库区淹没区土壤中重金属Cu,Pb,Cd,Cr的存在形态、迁移转化特征及其对水体水质的影响进行研究.结果表明:不同重金属在库区土壤中存在形态不同,Cu和Cr主要以残渣态存在,w(残渣态Cu)和w(残渣态Cr)平均值为87.41%和96.04%,而w(可提取态Pb)和w(可提取态Cd)较高,平均值为41.95%和88.14%,生态风险相对高于Cu和Cr.在汛期三峡水库低水位运行,水体重金属含量较高,汛期水体ρ(Pb)和ρ(Cd)分布特征与土壤w(Pb)和w(Cd)分布呈显著相关性,而汛后水库首次172 m高水位蓄水,由于水环境因素的改变,水体中重金属含量显著降低,汛后淹没土壤重金属形态含量变化细微,土壤淹没对库区水体水质影响小,不构成汛期、汛后水体重金属含量波动的主因.According to the off-season regulation model for the Three Gorges Reservoir during and after flood season,chemical fraction composition and the characteristic of transport and transfer of four heavy metals Cu,Pb,Cd and Cr in submerged soil of Three Gorges Reservoir Area were investigated,and their effect on water quality was analyzed.The results indicated that the chemical fraction composition characteristics of heavy metals were different.The amount of residual fraction of Cu and Cr reached 87.41% and 96.04% respectively,and the amounts of extractable Pb and Cd were 41.95% and 88.14% respectively,which have a higher ecological harm than Cu and Cr.High concentrations of heavy metals in water were found in flood season,and a significant positive correlation was observed between the distributions of Pb and Cd in soil and water.After flood season,the water level increased to 172 m,and lowered the amount of heavy metals in the water with the change of environmental condition.There was no significant change in chemical form of heavy metals in the submerged soil after flood season,and the movement and transformation of heavy metals in submerged soil have little effect on water quality.It is not the main reason for the concentration fluctuation of heavy metals in the water during and after flood season.

关 键 词：三峡水库 土壤 重金属 形态 迁移转化 

分 类 号：X143[环境科学与工程—环境科学]