Changes of Wetland Landscape Pattern Indexes in the Middle Reaches of the Huaihe Valley in China

Relief map of the middle reaches of the Huaihe Valley in 1950s, remote sensing images of 1980 and 2000 are utilized to abstract and interpret land use maps of the study area in different periods and also the distribution map of different wetland types on the basis of secondary classification of wetland. Landscape index analysis is applied to analyze and evaluate ecological changes of wetland landscapes in the middle reaches of the Huaihe Valley. The analysis results show that landscape pattern indexes change greatly from 1950s to 1980, but change slightly since 1980. Such a trend demonstrates that wetland landscapes in the study area change from diversified and complicate to unitary and fragmented, wetland system has drastically-reducing components, a great number of transitional zones become extinct, connectivity and heterogeneity of wetland landscapes are largely reduced, integrity and balance of wetland system is broken, as a result, ecological service functions of wetland degrade or cannot be fully utilized.