Alteration of Hydrological Regimes at Yichang Hydrological Station of Three Gorges Reservoir Since Impoundment for Two Decades
The Three Gorges Reservoir,impounded since 2003 for 20 years,has played a crucial role in flood pre-vention,hydropower generation,navigation,water resource utilization,and ecological environmental protection.However,its operation has also impacted downstream hydrological regimes.We analyzed daily runoff and water lev-el data from the Yichang hydrological station spanning from 1950 to 2022.Applying the MASH(Moving Average o-ver Shifting Horizon),Sen slope,and IHA/RVA methods,we quantitatively assessed the alterations in hydrologi-cal regimes following the Three Gorges Reservoir operation.Findings revealed significant trends in moving-average runoff,with increases during January-May and decreases during September-November,as well as decreasing mov-ing-average water levels from June to December.Fourteen IHA(Indicators of Hydrologic Alteration)showed sub-stantial alterations,resulting in an overall alteration of 63.52％,classified as moderate.The Three Gorges Reservoir notably enhanced the median values of annual minimum flow components and the number of flow reversals while de-creasing the median values of annual maximum 1-day flow through streamflow regulation.These adjustments reflect the reservoir's multifaceted benefits for flood control and hydropower generation.The research outcomes offer valua-ble insights for managing water resources within the Three Gorges Reservoir.
Three Gorges Reservoirhydrological regimeMASH methodIHA/RVA methodYichang hydrologi-cal station
国家科技期刊平台
NSTL
万方数据
