水利学报2025，Vol.56Issue(8)：1049-1060,1071,13.DOI:10.13243/j.cnki.slxb.20240802
三峡建库前后荆江沙质河段流量-输沙率关系及其变化机理
Sediment-transport rating curves and their variation mechanisms in sandy reach of the Jingjiang River before and after construction of the Three Gorges Reservoir
摘要
Abstract
The sediment-transport rating curves(STCs)in the sandy reach of the Jingjiang River have varied signifi-cantly due to the construction of the Three Gorges Reservoir(TGR),impacting channel-floodplain deformation dynamics.This paper examined the mechanisms underlying the variations in STCs influenced by TGR construction,utilizing hydrological,sediment,and river topography data,and analyzed their implications for channel-floodplain deformation.Main conclusions indicate that prior to TGR construction,the STC exhibited a downward deflection above bankfull discharge.This phenomenon was attributed to predominance of wash load transported in the main channel,which subsequently entered the floodplain as overbank flow and transformed into bed load.Following TGR construction,the deflection of STC above bankfull discharge disappeared,revealing a critical characteristic under low flow condition instead.Although overall channel-floodplain morphology and hydrodynamic regimes have not changed significantly since TGR construction,the coarsening of sediment particle size has led to qualitative shifts in sediment transport modes:from wash load to bed load above bankfull discharge,and from suspended load to bed load during dry periods.Influenced by altered sediment transport regimes,the main channel experiences significant scour,while sedimentation rates on the floodplain are markedly reduced.This understanding enhances our compre-hension of water-sediment transport mechanisms under both equilibrium and non-equilibrium conditions in a dammed sandy river,as well as long-term evolutionary trends of river channel.关键词
流量-输沙率关系/泥沙输移状态/滩槽冲淤/荆江河段/三峡水库Key words
sediment-transport rating curve/sediment transport mode/channel-floodplain deformation/Jingjiang River/the Three Gorges Reservoir分类
建筑与水利引用本文复制引用
周炜兴,孙昭华,杨中华,李芷晴,安姗姗..三峡建库前后荆江沙质河段流量-输沙率关系及其变化机理[J].水利学报,2025,56(8):1049-1060,1071,13.基金项目
国家自然科学基金项目(52479074) （52479074）
水利部三峡后续研究项目(12630100100020J005) （12630100100020J005）
