[Influence of 175-m-impoundment in Three Gorges Reservoir area on the food web energy sources of main commercial fishes in backwater area of xiaojiang River].
The impoundment in the Three Gorges Reservoir Area (TGRA) was first reached 175 m in 2010. To approach the influence of this impoundment on the food web energy sources of fishes in the tributaries of TRGA, an analysis was made on the food web energy sources of seven economically important fishes (Carassius auratus, Cyprinus carpio, Silurus asotus, Culter mongolicus mongolicus, Mystus macropterus, Pelteobagrus vachelli, and Pelteobagrus nitidus) in the backwater area of Xiaojiang River by using stable isotope method in combining with IsoSource Model. The results showed that before this impoundment (July 2010), microalgae were the main energy sources for the seven species. After this impoundment (December 2010), the contribution ratio of the microalgae decreased somewhat, while the relative contribution of terrestrial C4 plants had an obvious increase. Especially for crucian carp (C. auratus) and catfish (S. asotus), the contribution rate of the C4 plants reached 38-54% and 32-50%, respectively. After the impoundment, at least 30% of the energy resources of these two fishes were come from terrestrial C4 plants, suggesting that the impoundment in TGRA increased the contribution rate of exogenous terrestrial C4 plants as the energy sources of fishes.
Ministry of Education Key Laboratory of Freshwater Fish Reproduction and Development, School of Life Sciences, Southwest University, Chongqing 400715, China. libin2004xinyang@126.com
Bin
B
Li
Zhi-Jian
ZJ
Wang
Xing-Jian
XJ
Yue
Yong-Ming
YM
Wang
Li
L
Jin
Yao-Guang
YG
Zhang
D000818:Animals; D002681:China; D004734:Energy Metabolism; D005399:Fishes / Q000145:classification / Q000254:growth & development*; D020387:Food Chain; D058086:Microalgae; D010839:Phytoplankton; D045483:Rivers; D014881:Water Supply