马过河流域梯级开发对植被及景观格局的影响研究

以金沙江一级支流马过河流域为研究对象，在GIS支持下，分析水利工程建设前后(2002年～2013年)流域土地利用类型、植被覆盖度变化；应用缓冲区分析法，选取斑块密度、边缘密度、分维数、蔓延度、香浓多样性指数等对景观结构变化进行评价，分析了水利工程建设前后流域景观结构的变化.结果表明：流域内不同地利用类型均发生了变化，流域尺度上表现为人工表面、水田面积明显增加，草地、水体、灌木等面积明显减少，但流域主要植被类型未发生变化，仍以森林为主；高覆盖度植被分布面积有一定程度减小，但总体仍以中覆盖度、中高覆盖度和高覆盖度面积最大；2013年的斑块密度、边缘密度、分维数值均高于2002年，2013年蔓延度指数低于2002年，香浓多样性指数变化不大；水利工程建设使区域景观异质性增强，在水电开发缓冲区1 000 m范围内景观格局变化明显， 1 000 m范围外变化减弱.

Impact of cascade hydropower development on vegetation and landscape in Maguohe River Basin

Taking the tributary of Jinsha River， Maguohe River Basin， as research object， we studied the change of land use type and vegetation resulted from hydropower development based on GIS and buffer analysis. Fractal dimension， patch density， edge density， contagion index and Shannon diversity are chosen to quantify the landscape pattern change. The results show that land use has changed in the basin. The area of artificial surface and paddy field increased significantly， while the area of the grass， water， shrubs reduced. However， the main vegetation type is still forest in the basin. Vegetation coverage has changed little， but the area with high vegetation coverage has decreased. The hydroelectric project might enhance landscape heterogeneity. Landscape pattern changed significantly within 1 000 m buffer zone.