Study of the influences of Three Gorges project's initial operation on river regime of the middle and lower Yangtze River
Since the impoundment and power generation of the Three Gorges project on June 1, 2003, river regime of the lower reach has experienced a great change. Up to 2006, the sediment runoffs at Yichang, Hankou and Datong are 0. 0702, 0. 134 and 0. 163 billion tons, or 86% , 67% and 62% less than the mean annual values, respectively. Sediment grain size at all the hydrologic stations is coarsened, particularly at Jianli where an increase from 0. 009mm to 0. 150mm in grain size was observed. Meanwhile, bed erosion has been intensified significantly resulting in a lower water level. Between Yichang to Hukou where main channel erosion dominates, the erosion volume in the main channel below flood plain from Oct. 2002 to Oct. 2006 is 6.14 × 10~8in~3. In comparison with 2002, the water level at Yichang after the flood season of 2006 is lowered by about 0.07m and 0. 49m at flow rates 4000m~3/s and 10000m~3/s, respectively.
river sedimentation engineeringThree Gorges projecthydrological regimeerosion of riverbed
国家科技期刊平台
NSTL
万方数据
维普
