长江科学院院报2019，Vol.36Issue(2)：13-19,7.DOI:10.11988/ckyyb.20170892
三峡工程运用前后沙市段河床形态调整特点
Riverbed Geomorphic Adjustments in the Shashi Reach before and after the Operation of Three Gorges Project
摘要
Abstract
Over the past five decades, the Shashi reach has undergone significant channel evolution due to the artifi-cial cut-off and the operation of the Three Gorges Project ( TGP). According to the measured hydrological and topo-graphic data in the past five decades, the variations in reach-scale amplitude of thalweg shifting and bankfull di-mensions are calculated in order to quantify the adjustments in channel planform and cross-sectional profiles in the Shashi reach.Results show that: (1) after the artificial cut-off project in the lower Jingjiang River, the mean ampli-tude of thalweg shifting at reach-scale was 30.8 m/a in 1966-1987, indicating a drastic adjustment in river regime;in 1987-2002,the thalweg was relatively stable, with the mean shifting amplitude reducing to 19 m/a; afterwards, the mean shifting amplitude increased to 32.6 m/a in 2003-2015 owing to the operation of the TGP. (2) Bed de-formation was remarkable at some typical sections of Taipingkou point bar and Jincheng island before the operation of TGP, but became relatively insignificant after the TGP. However, obvious bed deformation continuously occurred at the typical sections of Sanba central bar. (3) After the TGP operation, bankfull channel adjustment in the Shashi reach was mainly represented by increases in bankfull depth and cross-sectional area, with an insignificant increase in bankfull width. In addition, power function relationship was established between the reach-scale bankfull dimen-sions and the five-year average fluvial erosion intensity during flood seasons, which can be used to reflect the ad-justments in reach-scale bankfull dimensions.关键词
河床调整/洲滩演变/三峡工程/平面形态/断面形态/沙市河段Key words
riverbed adjustment/bar evolution/Three Gorges Project/plane morphology/sectional morphology/Shashi reach分类
建筑与水利引用本文复制引用
李溢汶,夏军强,邓珊珊,周美蓉..三峡工程运用前后沙市段河床形态调整特点[J].长江科学院院报,2019,36(2):13-19,7.基金项目
国家重点研发计划课题(2016YFC0402305) （2016YFC0402305）
国家自然科学基金项目(51579186,51725902) （51579186,51725902）
三峡后续规划研究课题(CKSG2016874/HL) （CKSG2016874/HL）
