Using remote sensing to monitor wetland cover change and succession in Dongting Lake of China during 1993-2010

This paper illustrates the results of wetland cover change and succession law in Dongting Lake of China using muti-temporal remotely sensed data from 1993 to 2010. The decision tree classification technique was used to extract information from satellite data. Then a series of post-classification methods were applied to obtain better results. Furthermore, we modified the classification results manually to rectify the errors caused by computer automatic classification. So the accuracy of the classification maps was satisfactory. The analysis indicated that woods and grass expansion of Dongting Lake resulted in the reduction of water (including lake-grass and water bodies), mud flat and reeds from 1993 to 2010. The maps between 2002 and 2006 showed dramatic change of the wetland cover. In the period of 2002-2010, regional differences in wetland cover change were obvious in West Dongting Lake and South Dongting Lake, especially West Dongting Lake, in which great changes of woods, reeds and grass had taken place. On the whole, 6.30% of the wetland changed, and 67.84% of that was successive succession. Sediment siltatio and human activity were the two factors that affect the wetland development and succession of Dongting Lake and oxbow of the Yangtze River. The study quantified the patterns of wetland cover change in Dongting Lake for the past four periods that forms valuable resources for wetland administration and decision makers to devise sustainable wetland environmental planning.