Acta Geographica Sinica ›› 2002, Vol. 57 ›› Issue (1): 76-84.

The Morphological Response of Typical Mud Flat to Sea Level Change in Jiangsu Coastal Plain

YANG Gui-shan, SHI Ya-feng, JI Zi-xiu

1. Nanjing Institute of Geography and Limnology, CAS, Nanjing 210008, China
• Received:2001-02-21 Revised:2001-10-22 Online:2002-01-25 Published:2010-09-06
• Supported by:

Excellent thesis for doctor's degree foundation of CAS; National Natural Science Foundation of China, No. 49871076

Abstract:

The morphological and ecological response of tidal flat and coastal wetlands to sea level rise is one of the basic aspects of the impacts of global warming on coastal zones. Jiangsu coastal plain, located in the middle of China's coastal area, is the vastest area with most diversiform ecological types of mud flat in China, even all over the world. Therefore, research on the morphological response of mud flat to sea level change in this area undoubtedly is typical and of global significance. Based on the 112 times of field elevation measurements to 19 typical sections since 1980, using statistic methods, the morphological response of typical accretion and erosion section of mud flat to sea level rise was discussed in this paper. The estimated results show that, there are good correlations between accretion rate (both the horizontal and the vertical) of mud flat and sea level change in the study area, just the correlation is diverse in different sections or different parts of the same section due to the various distributions of current velocity and silt flux. The general tendency of the response of mud flat to sea level rise is that the accretion will tend to slow down and erosion will tend to be intensified. To typical accretion section, when sea level rises, the parts of mud flat above mean tidal line will still accrete, but the accretion rate will decrease except the part around mean high tidal line, the speediest rate of accretion occurs in the part between mean high tidal line and that one of the neaps. Whereas, the parts below mean tidal line will experience more intense erosion. The convex profile of mud flat will become more and more steeper and curving due to the upper side accreting and the down side eroding. To typical erosion section, the response of mud flat profile to sea level rise will present a opposite trend. The parts above mean tidal line will be eroded intensively, but the parts below mean tidal line will accrete. The concave profile will become more and more straight.