Chemical Characteristics and Geochemical Processes of High Arsenic Groundwater in Different Regions of China(PDF)
《地球科学与环境学报》[ISSN:1672-6561/CN:61-1423/P]
- Issue:
- 2013年第03期
- Page:
- 83-96
- Research Field:
- 水资源与环境
- Publishing date:
Info
- Title:
- Chemical Characteristics and Geochemical Processes of High Arsenic Groundwater in Different Regions of China
- Author(s):
- GUO Hua-ming; GUO Qi; JIA Yong-feng; LIU Ze-yun; JIANG Yu-xiao
- 1.Key Laboratory of Groundwater Circulation and Evolution of Ministry of Education, China University of Geosciences, Beijing 100083, China; 2. School of Water Resources and Environment, China University of Geosciences, Beijing 100083, China
- Keywords:
- groundwater; arsenic release; water chemical characteristic; hydrogeochemistry; arsenic enrichment mechanism; arsenic species; reductive dissolution; desorption
- PACS:
- P641
- DOI:
- -
- Abstract:
-
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 these environments, mass concentrations of SO42- and NO3- are generally low. Mass concentration of SO42- 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.
Last Update: 2014-01-20