Qibo H.,Wuhan University |
Qibo H.,Chinese Academy of Geological Sciences |
Qibo H.,Karst Laboratory of Karst Dynamics |
Xiaoqun Q.,Chinese Academy of Geological Sciences |
And 7 more authors.
Environmental Earth Sciences | Year: 2016
Karst groundwater is one of the most important water resources for agriculture and industry in Fenyang City of Shanxi province, northern China. In the last few decades, excessive exploitation of groundwater and other human activities have caused serious environmental problems in this area. Hence, it is essential to identify the resources of pollutants that deteriorate the water quality in the area. A total of 16 water samples were collected to assess the hydrochemical characteristics from wells and springs in bare karst area, northern Fenyang and covered karst region, south of the city. The chemical composition of groundwater was characterized by a dominance of Ca2+, Mg2+, HCO3 −, and SO4 2−, which accounted for more than 85 % of the total ion concentrations, indicating that limestone dissolution by weathering controls water chemical composition. SO4 2− in the groundwater showed high positive significant correlation with HCO3 − and δ13CDIC, showing that carbonate dissolution by sulfuric acid has important contribution to groundwater chemical composition and δ13CDIC value. The relationship between δ34S and 1/SO4 2− revealed that the sources of SO4 2− are different in various types of groundwater. In the bare karst area, SO4 2− in springs mainly came from atmospheric precipitation, while in the shallow wells it mainly came from human activities; in the covered karst region, SO4 2− in quaternary pores water was mainly from anthropogenic inputs, while in the deep wells it was mainly from gypsum dissolution; in gypsum mine water, SO4 2+ was mainly from gypsum dissolution. Comparing with the bare karst area, human activities have significantly changed the chemical composition of groundwater in the covered karst region. Therefore, more control policies and measures should be formulated and applied to protect the covered karst region in the future. © 2015, Springer-Verlag Berlin Heidelberg.
Huang Q.-B.,Wuhan University |
Huang Q.-B.,Chinese Academy of Geological Sciences |
Huang Q.-B.,Karst Laboratory of Karst Dynamics |
Qin X.-Q.,Chinese Academy of Geological Sciences |
And 10 more authors.
Huanjing Kexue/Environmental Science | Year: 2016
The Wujing River, the largest river in Guizhou Province, is one of the most important water resources for social and economical development. Recently, with the fast population proliferation and rapid economic growth, the drainage basin is intensively interfered by anthropogenic activities. The hydrochemistry of surface water was analyzed from the upper-middle reaches of Wujiang River for investigating the hydrochemical characteristics and their main influencing factors. The results showed that the major cations of the four rivers were Ca2+ and Mg2+, accounting for more than 70%, and the main anions were HCO3 - and SO4 2-, occupying more than 85%. The hydrochemical characteristics in the four rivers were found to be of HCO3-Ca type, and mainly determined by the carbonate rock dissolution, while only a small proportion of them were of HCO3·SO4-Ca type, reflecting the influence of SO4 2- from anthropogenic activities. Compared to hydrochemical data in 1999, there was an obvious increase in cations and anions concentrations, majorly in NO3 -, SO4 2- ion concentrations, which were significantly affected by human activities. The Na+, K+, Cl- in the river mainly came from atmospheric precipitation, and Ca2+, HCO3 -, Mg2+ mainly came from carbonate rocks dissolution, while NO3 - and SO4 2- mainly came from human activities. According to principal component analysis and correlation analysis, hydrochemical composition of Liuchong River was affected by human activity, and that in the upstream of Sancha River was controlled by atmospheric precipitation and the dissolution of carbonate rocks, that to the downstream was enhanced by human activities. The main ion of Maotiao River was controlled by atmospheric precipitation and carbonate rocks dissolution, and also affected by human activity. The Nanming River, the Qingshui river's tributary, was mainly affected by human activity, while the middle and lower reaches of Qingshui River were affected by both the atmospheric precipitation and human activity. © 2016, Science Press. All right reserved.