中文摘要：

在简述黄河河口尾闾河段相关特征的基础上，从河槽横断面形态、河床纵剖面形态包括主槽河底平均高程、河床纵比降、平滩流量变化等方面分析了黄河河口尾闾河段河床形态萎缩特征。清水沟流路在1976—2000年期间，黄河口尾闾河段的发育大致可分为4个阶段，即初期发育阶段、中期成型阶段、后期萎缩阶段、末期人工干预发展阶段。相应的发育时期分别为20世纪80年代中期以后，尾问河段主槽宽深比上升、横比降升高、河段纵比降下降、河床平均高程抬升，其相应时期内河道平滩流量相对偏低。这一现象可能与黄河来水来沙偏枯相关。河道疏浚、人工出汉、调水调沙等措施对尾闾河段河床形态的萎缩有一定的抑制作用，但其影响是暂时的，不能改变河道萎缩的总体趋势。

英文摘要：

Based on related characteristics of the tail of the Yellow River mouth, shrinkage on riverbed form was analyzed with channel transect form and riverbed longitudinal profile morphology. The latter includes the average elevation of main channel bed, riverbed longitudinal degradation and bank-full discharge. In the course of 1976 to 2000, there were four stages for growth of the tail of the Yellow River mouth in Qingshuigou Course, i.e. earlier growth stage, medium-term molding stage, later shrinkage stage and last development stage under artificial interference. Corresponding with above four stages, the rate of width and depth of main channels of the tail of the River mouth increases, horizontal degradation rises, riverbed longitudinal degradation descends, and average riverbed elevation uplifts. And bank-full discharge is correspondingly low during corresponding stages. These phenomena are related with dried water and sediment discharge. River dredging, artificial diversion of river course and water and silt regulation can restrain shrinkage on riverbed form of the tail of the Yellow River mouth, but it is temporary and cannot change the total tendency of riverbed shrinkage.