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As one of three important ecosystems in the world ,wetland has complex, various and specific functions. With the
change of its component, the wetland ecosystem function is changing . Analyzing the process of wetland landscape
change can expose the mechanism and rules of wetland landscape change and provide academic supply for sustainable
use of wetland resource. In this paper the landscape pattern change of Dongting Lake wetland was studied. Dongting
Lake wetland is one of the most important wetland ecosystems in China and it has complex and various functions and
values.From 1980 to 2000,Dongting Lake wetland changed gradually due to natural factor and human activities.In order
to better understand physical and human effect on wetland, protect and use the wetland resources sustainably in
Dongting Lake area, it is necessary tor study the change of wetland landscape in Dongting Lake area. Some indices of
the landscape pattern, such as landscape diversity index, landscape dominance index, landscape fractal dimension index
are adopted .This study was on the basis of Chinese Academy of Sciences resource and environment spatial-temporal
database and the two-stage remote sensing data: Landsat MSS data captured in 1980 and Landsat TM/ETM data
captured in 2000. The result showed that wetland area increased by 16307hm2, of which paddy field and riverwetland
decreased largely, but pond wetland area increased obviously.Totally artificial wetland area increased, while natural
wetland decreased. Accordingly the landscape pattern indices changed with the changes of area and perimeter of several
wetland types in Dongting Lake. These changes are the result of interactions between human activities and natural
factor.But the human impact on wetland is the most important causation in the past two decades. The changes of wetland
landscape made environmental quality and ecological function decade in Dongting Lake area, especially the flood
disaster aggravate.
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