Natural Reproduction of Chinese Sturgeon During the 175m Trial Impoundment of Three Gorges Dam

• 作 者: Jiang Wei Jiang Hua Tang Xiliang Huang Tao Gao Yong
• 机 构: Institute of Chinese Sturgeon, China Three Gorges Corporation, Yichang , China
• 出 处: 三峡工程正常蓄水位175米试验性蓄水运行十年学术研讨咨询会
• 发表日期: 2018年8期
• 关键词: chinese sturgeon three gorges dam natural reproduction

　　the three gorges dam was located about 38 km upstream the gezhouba dam,the 175m impoundment of three gorges dam may influence the natural reproduction of chinese sturgeon.therefore,the 2-years investigation was conducted according 5 methods from 2009-2010 to analysis the influence.according the investigation,chinese sturgeon reproduced once from the midnight of november 23 to the early morning of november 24 in 2009.the spawning sites was located in the 1.5 km downstream the gezhouba dam.the water flow was 5774 m3/s,water level was 40.24 m and mean water temperature was 19.8 ℃ during the reproduction.the reproduction was occurred from the midnight of november 21 to the early morning of november 22 in 2010.the spawning sites was located between the 500~1000 m down-stream the gezhouba dam.the water flow was 6420 m3/s and mean water temperature was 19.9℃.in 2009,a total of 241 chinese sturgeon eggs and 82 larvae were collected in the early resource investiga-tion,a total of 3370 eggs were collected from the eggs-predator investigation,4 chinese sturgeon sonar signals were obtained from the hydro-acoustic investigation,and 2 chinese sturgeon were recorder in the didson investigation.in 2010,a total of 72 chinese sturgeon eggs and 20 larvae were collected in the early resource investigation,none eggs were collected from the eggs-predator investigation,7 chinese sturgeon sonar signals were obtained from the hydro-acoustic investigation.all the monitoring date from 1997-2010 showed that the chinese sturgeon could finish natural reproduction while the three gorges dam oper-ating the 175 m trial impoundment,but spawning time was later and water temperature when spawning was slight higher than before.therefore,impoundment earlier to avoid the spawning time of chinese sturgeon may be available to reduce the influence to the natural reproduction of chinese sturgeon.