Acta Geographica Sinica ›› 2006, Vol. 61 ›› Issue (3): 282-288.doi: 10.11821/xb200603007

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Drastic Decrease in Sediment Supply from Yangtze River and Coastal Crisis

LI Ming, YANG Shilun, LI Peng, LIU Zhe, DAI Shibao, GAO Ang, ZHANG Jing   

  1. State Key Lab of Estuarine and Coastal Research, East China Normal University, Shanghai 200062, China
  • Received:2005-12-02 Revised:2006-01-04 Online:2006-03-25 Published:2006-03-25
  • Supported by:

    National Natural Science Foundation of China, No.40576043; National 973 Project, No.2002CB412407; Project of Shanghai Commission of Science and Technology, No.04DZ19305; No.04DZ12049


The periodicity and trends of 1951-2004 time series of water and sediment discharges at Datong Station and precipitation in the catchment were analyzed using wavelet method. Bathymetric data were processed for coastal area and profile using Arc-GIS software. A typical intertidal flat was daily measured from May 2002 to August 2005 for comparison of bed level between pre- and post-impoundment of the Three Gorges Reservoir. The results indicate that the sediment discharge shows a decreasing trend from the late 1960s (P < 0.001) while it varies in periods of 2-3 years and 8-9 years together with water discharge and precipitation. The decreasing trend is attributed mainly to dam construction while the periodicity is attributed to climate variability. After the impoundment of the Three Gorges Reservoir, the sediment discharge was reduced to the lowest level in the history. As a result of the drastic decrease in riverine sediment supply, the delta is transforming from progradation to recession. The sediment supply from the Yangtze is forecasted to decrease from 1.5×108-2×108 t/a at the present to -1×108 t/a in the coming decades, which will result in crisis of coastal resources.

Key words: sediment discharge, intertidal tidal flat, delta, Yangtze River