FEI Zhijun1, WANG Zhuhong1, TANG Yang2
(1. School of Public Health, Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang 550025, China;
2. State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China;
3. Key Laboratory of Karst Environment and Geohazard Prevention, Guizhou University, Guiyang, 550025, China)
Abstract: Aha lake, a seasonal anoxic lake and a drinking water source in southwestern China, was selected for this research. Summer (July, rain season) and winter (November, dry season) water samples were collected from 12 locations around the reservoir. Thirteen trace elements (As, Co, Cr, Cd, Fe, Cu, Zn, Ni, Pb, Mo, Mn, Hg and Se) were determined and compared with different water quality standards, furthermore, the distribution characteristics and possible sources were analyzed by correlation analysis and principal component analysis. The results showed that the order of heavy metal concentrations in summer was: Mn>Fe>Ni>Co>Zn>Cu>As>Cr>Cd>Pb>Hg, while, the order in winter was: Mn>Fe>Zn>Ni>As>Cu>Co>Cr>Pb>Hg>Cd. The temporal variations of heavy metal concentration was influenced by the seasonal Fe-Mn redox reaction. Youyu River, as the main tributary of the reservoir, was significantly impacted by the coal mining activities that contribute a lot of Fe and Mn in the water system. Baiyan River and Jinzhong River were mainly influenced by the agricultural cultivation and urban domestic sewage, respectively. Correlation and principal component analysis showed that Co, Cd, Fe were significantly positively correlated with Zn, Ni and Mn in summer, and As was positively correlated with Cr, Mo and Se. Besides, there was a distinct positive correlation between Cu and Pb, while insignificant correlation was found between Hg and other heavy metals. Cd, Zn, Ni, Co、Fe and Mn were the main heavy metal elements around the reservoir and had the same origin that was influenced by the mineral exploitations.
Key Words: Aha lake; Heavy metal; Distribution characteristics; Source
EARTH AND ENVIRONMENT Vol.49, No.1, Tot No.339, 2021, Page 42-50