用户名: 密码: 验证码:
Chemical Characteristics and Geochemical Processes of High Arsenic Groundwater in Different Regions of China
详细信息   
摘要


     High arsenic groundwater has been widely found in two kinds of regions including arid inland basin and humid river delta in China, which seriously affects resident health. Hetao Basin, Huhhot Basin, Yinchuan Basin and Datong Basin were selected as the arid inland basins, and Pearl River Delta and Jianghan Plain as the humid river deltas. Chemical characteristics and hydrogeochemical processes of high arsenic groundwater in different regions of China were analyzed. The type of high arsenic groundwater is HCO3-Ca in Jianghan Plain, HCO3-Na in Datong Basin, Hetao Basin and Yinchuan Basin, and Cl-Na in Pearl River Delta. Oxidation- reduction potential in high arsenic groundwater is low, indicating reduction environment. In theseenvironments, mass concentrations of SO4^2- and NO3 are generally low. Mass concentration of SO4^2- in Jianghan Plain is the lowest among all the six regions, while that of NO3 in Hetao Basin is the lowest. There is no significant correlation between mass concentrations of As and Fe. Mass concentrations of Fe and Mn are the highest, but As is relatively lower in Pearl River Delta, and mass concentrations of Fe and Mn are the lowest, but As is relatively higher in Datong Basin. Weathering, cation-exchange adsorption and reduction occur in high arsenic groundwater system. Pyrite precipitation may be an important process for controlling mass concentrations of Fe and As in addition to reductive dissolution of Fe/Mn oxides in Hetao Basin and Huhhot Basin. However, reductive dissolution of Fe/Mn oxides and Fe II re adsorption are the major hydrogeochemical processes in Jianghan Plain. Desorption of adsorbed arsenic also contributes to arsenic enrichment in groundwater of arid inland basins with weak alkaline environment.

© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号

地址:北京市海淀区学院路29号 邮编:100083

电话:办公室:(+86 10)66554848;文献借阅、咨询服务、科技查新:66554700