泥沙研究2025，Vol.50Issue(6)：53-60,8.DOI:10.16239/j.cnki.0468-155x.2025.06.008
拉萨河下游典型辫状河道演变特征及趋势
Characteristics and trends of channel evolution in the typical braided Reach of the Lower Lhasa River
摘要
Abstract
Based on the calculations by a one-dimensional hydrodynamic model and the analysis of satellite re-mote sensing images,the river evolution characteristics and its development trends of the Niedang Reach in the Lower Lhasa River have been analyzed.The results indicate that the Niedang Reach is characterized by wide and shallow channel in geometry with cross-sectional width-to-depth ratio of 663.2～5 729.4,exhibiting typi-cal braided characteristics.The flow area and water surface width are smaller in the single narrow reaches,while are larger in the braided channels.With the human intervention and natural evolution,the reaches a-round the Niedang ecological island and the industrial zone have shifted from an active to relatively stable sta-tus.The mid-bars in the reach near the Niedang town have experienced drastic adjustment with frequently ero-sion,cutting and merging.The operation of upstream reservoirs and barrages are beneficial for stabilizing downstream channel pattern.However,the instability risk of unprotected sandbars increases in medium-to-high flow conditions exceeding 1 200 m3/s,which causing drastic adjustments of river morphology in braided chan-nels,especially in the reach near the Neidang town.The research can provide a scientific basis for the evolu-tion and management of braided river channels in the Lower Lhasa River.关键词
拉萨河下游/辫状河道/河道演变/河道水力几何特征Key words
Lower Lhasa River/braided channels/channel evolution/channel hydraulic geometry分类
建筑与水利引用本文复制引用
杨绪海,李志晶,金中武,周银军,吴华莉,刘亚..拉萨河下游典型辫状河道演变特征及趋势[J].泥沙研究,2025,50(6):53-60,8.基金项目
国家自然科学基金重点项目(52239007) （52239007）
中央级科研院所基本科研业务费项目(CKSF2024984,CKSF2024985,CKSF2024988) （CKSF2024984,CKSF2024985,CKSF2024988）
