Spatial and Temporal Change and Its Driving Forces of the Raoyanghe Wetlands Based on RS and GIS

Based on the remote sensing data(TM,ETM+,CBERS) during the flood period (1975-2007),the transfer matrix of wetland types were extracted using RS and GIS software,and the spatial and temporal change of marsh wetlands and its driving forces were analyzed from 1975 to 2007 by using barycenter transfer model. The results showed that:From 1975 to 2007,the area percent of Raoyanghe marsh wetlands decreased from 1.908% to 0.068%,which resulted in the converting of marsh into rice paddy field and bare land. Barycenter of Raoyanghe marsh wetlands had moved 1.58 km towards northeast from 1975 to 1988,and 3.21 km towards southwest from 1988 to 2007. Barycenter of Raoyanghe marsh wetlands had moved 2.36 km towards southwest from 1975 to 2007. The distance between barycenter of Raoyanghe marsh wetlands and river decreased by 1.79 km. Spatial and temporal change of rice paddy field is the immediate driving force. The marsh wetlands area has a significant negative correlation relation with the burying depth of groundwater and economy activities,while has a significant positive correlation relation with river area. In one word,human activities are the main driving forces of spatial and temporal change of Raoyanghe marsh wetlands.