Abstract

Evolution of Changjiang Estuary from estuarine bay to estuarine delta by fluvial processes of deposition-erosion and bar-shoal banking and combination is firstly described in this paper. Basic characteristics of bar-shoal banking and combination are summarized. Relationship between present overall river-regime of Changjiang Estuary and processes of bar-shoal banking and combination is then analyzed. Characteristics of recent bar-shoal evolution and river-pattern transformation of Changjiang Estuary are further probed. Finally, it is pointed out that key to control river-regime of Changjiang Estuary is regulation of the North- and South-port bifurcated Waterways, which involves regime-control measures for islands of Lower Biandansha, Zhongyangsha, Qingcaosha, New Liuhesha and Ruifengsha etc., and maintenance of New-bridge Waterway. These measures are crucially related to long-term relative stability of the North- and South-port Waterways through avoiding the North-port Waterway to rehearse the same disastrous destiny of the North Branch.

Keywords: Changjiang Estuary, Changjiang Delta, fluvial processes, bar-shoal banking and combination, overall river-regime, regulation of the North- and South-port Waterways