Impacts of river impoundment on the riverine water chemistry composition and their response to chemical weathering rate  

作　　者：Yang GAO Baoli WANG Xiaolong LIU Yuchun WANG Jing ZHANG Yanxing JIANG 

机构地区：[1]School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China [2]Institute of Geochemistry, Chinese Academy of Science, Guiyang 550002, China [3]Tianjin Normal University, Tianjin 300387, China [4]Department of Water Environment, China Institute of Water Resources and Hydroelectric Power Research (IWHR), Beijing 100038, China

出　　处：《Frontiers of Earth Science》2013年第3期351-360,共10页地球科学前沿（英文版）

基　　金：The authors thank Ituihui Li, Zhiwei Hart, Chipeng Zhang, Yan Yang and Ganrong Li for their careful assistances in field sampling. This research was funded by the National Natural Science Foundation of China （Grant Nos. 41273128 and 40873066）, and the Shanghai Education Committee Fund （12YZ017 ）.

摘　　要：Currently, most rivers worldwide have been intensively impounded. River damming becomes a big problem, not only in inducing the physical obstruction between upstream and downstream, but also in destroying the natural continuity of river. But the discontinuity of water quality was often neglected, which presents a challenge to traditional river geochemistry research. To understand the changes in basic chemistry of water upstream and downstream of the dam, we investigated the Miaotiao River reservoirs in series in the Wujiang River Basin, and the Hongjiadu, Dongfeng Reservoir on the upper reaches of the Wujiang River. Chemical weathering rates were calculated using the water chemistry data of the reservoir surface and downstream of the dam, in each reservoir, respectively. The results showed that the difference between the chemical weathering rates calculated from reservoir surface water and water downstream of the dam was greater in reservoirs with a longer water retention time. In Hongjiadu Reservoir with the longest water retention time among the studied reservoirs, this difference reaches 9%. As a result, the influence of fiver damming, especially the influence of reservoirs in series, should be taken into account when calculating the chemical weathering rate of a fiver basin.Currently, most rivers worldwide have been intensively impounded. River damming becomes a big problem, not only in inducing the physical obstruction between upstream and downstream, but also in destroying the natural continuity of river. But the discontinuity of water quality was often neglected, which presents a challenge to traditional river geochemistry research. To understand the changes in basic chemistry of water upstream and downstream of the dam, we investigated the Miaotiao River reservoirs in series in the Wujiang River Basin, and the Hongjiadu, Dongfeng Reservoir on the upper reaches of the Wujiang River. Chemical weathering rates were calculated using the water chemistry data of the reservoir surface and downstream of the dam, in each reservoir, respectively. The results showed that the difference between the chemical weathering rates calculated from reservoir surface water and water downstream of the dam was greater in reservoirs with a longer water retention time. In Hongjiadu Reservoir with the longest water retention time among the studied reservoirs, this difference reaches 9%. As a result, the influence of fiver damming, especially the influence of reservoirs in series, should be taken into account when calculating the chemical weathering rate of a fiver basin.

关 键 词：reservoirs in series chemical weathering rate Wujiang 

分 类 号：TV543[水利工程—水利水电工程] P343.3[天文地球—水文科学]