Study on the Landscape Pattern Changes and the Landscape Development Intensity of Caohai National Nature Reserve, Guizhou

Landscape pattern changes and landscape development are indicators of wetland ecosystem health. By interpreting multi-temporal TM images of 1974, 1992, 2001 and 2015 of Caohai National Nature Reserve, based on remote sensing and geographic information system, and field investigation on the Caohai wetland, the landscape was classified into 7 elements as, cultivated land, forest land, wasteland, mudflat, meadow swamp, building site and lake. And 5 landscape indexes, i.e. landscape patches area, landscape diversity index, landscape dominant index, landscape evenness index and landscape fragment index were chosen to analyze the landscape character, landscape pattern change and landscape development. The results show that, the landscape diversity index, landscape dominant index, landscape evenness index and landscape fragment index presented large fluctuation, affected by multiple factors including the natural driving factors such as climate change, precipitation, soil erosion and water eutrophication, and human driving factors such as population and economic growth, land use, industrial and agricultural pollution during the 4 periods. Additionally, the mean landscape development intensity index (I_{LD, total}) of the 4 periods was 4.00±0.24, which reached to the highest value in 2015 (I_{LD, 2015}=4.27), indicates that Caohai wetland belonged to agricultural wetland type, in which the agricultural uses in the watersheds were primarily row crops and pasture. The Caohai wetland is shifting to unban wetland type with the rapid development of urban construction. So, reasonable configuration of the wetland landscape is a comprehensive management measures to ensure the healthy development of ecological environment in Caohai National Nature Reserve.