珠江三角洲网河近20年河床演变特征分析

总结了20世纪80年代前珠江三角洲网河河床演变特征,并采用80年代和90年代末的河道地形图,通过对比珠江三角洲各主要河道的深泓线、平均河底高程以及河道容积、河床断面宽深比的变化,分析珠江三角洲80年代后的河床演变特征。对比分析结果表明珠江三角洲在不同时期呈现出不同的河床演变规律——20世纪80年代前以淤积为主,80年代至90年代末转变为以冲刷为主。

Characteristic analysis of fluvial process of river network in Pearl River Delta for recent 2 decades

The characteristics of fluvial process of river network in Pearl River Delta before 1980s were summarized. With the topographical data of river network in 1980s and at the end of 1990s, the characteristics of fluvial process after 1980s were analyzed by comparison of the variations of the talweg and capacity of the main river courses, the average altitude of the riverbed, and the width-to-depth ratio of riverbed profiles. It was concluded that the fluvial process was different in different periods of time: most river courses in the Pearl River Delta were characterized by deposition before 1980s, and erosion from 1980s to the end of 1990s.