近30年黄河源头土地覆被变化特征分析  

Characteristic of Land Cover Changes in the Yellow River Headwaters Region over the Past 30 Years

作　　者：邴龙飞[1,2] 邵全琴[1] 刘纪远[1] 

机构地区：[1]中国科学院地理科学与资源研究所,北京100101 [2]中国科学院研究生院,北京100049

出　　处：《地球信息科学学报》2011年第3期289-296,共8页Journal of Geo-information Science

基　　金：国家科技支撑计划(2006BAC08B00);国家科技支撑(攻关)(2009BAC61B01)资助;中国科学院西部行动计划项目(KZCX2-XB2-06-03)

摘　　要：本研究对以DEM生成的黄河源头范围内的土地覆被变化进行了分析,得到20世纪70年代中后期至80年代末、80年代末至2004年和2004-2008年土地覆被变化数据。同时利用转移矩阵的方法,定量研究了近30年黄河源头土地覆被类型转移的途径和幅度;分析了3个时段内的土地覆被状况指数和土地覆被转类指数,藉此探讨黄河源头不同土地覆被类型的生态系统功能的变化:黄河源头土地覆被类型以草地为主,草地覆被状况明显优于同时期三江源的总体状况。1970-2004年,黄河源头土地覆被状况呈持续退化的趋势,而且不同时段内土地覆被状况变动较大;2004-2008年草地退化的趋势得到明显的遏制。从70年代到2008年,黄河源头流域尺度宏观生态状况经历了变差-缓慢恢复的趋势,2004年开始实施生态保护工程以后,黄河源头草地覆被状况出现了好转的趋势。Research on land cover change with different definition of the Yellow River headwaters region is of great significance.But there was no unified definition of the Yellow River headwaters region.Different definition made different result.The land cover condition in the Yellow River headwaters region derived from Digital Elevation Model（DEM） was adopted to explore its changes during three periods,i.e.1970s to late 1980s,late 1980s to 2004 and 2004 to 2008.The outlet of watershed used in this paper was Jimai hydrologic station in order to minimize climate effect.The mathematical index was used to study the ecological effect of grassland degradation quantificationally.In this paper we discussed the direction and extent of land cover changes over the past 30 years with the method of transfer matrix;then it analyzed the land cover condition index and land cover change index,to detect the ecosystem function variance owing to land cover change in the Yellow River headwaters region.The land cover condition index considered only the main factors which were of great importance on ecosystem functions,such as forestry shrub,high coverage of grassland,water body and swamp.It assumed that these four land cover types were of better ecosystem services.The present state of land cover was listed at the very beginning of the result.The dominant land cover type was grass,which was better than that in the Three-River Headwaters Region during all the four periods.The land cover condition was degrading from 1970 to 2004,and fluctuating greatly in different periods,and restoring ever since 2004.The macro ecosystem condition,which was described by land cover change index,experienced a course of melioration,i.e.slow restoration in the Yellow River headwaters region from 1970s to 2008.The grass land condition has been becoming better ever since the ecological conservancy project was executed from 2004.Climate change influenced the degradation of grassland greatly,but the ecological restoration made some positive effects on ecological evo

关 键 词：黄河源头 土地覆被 指数 生态系统 

分 类 号：P208[天文地球—地图制图学与地理信息工程] F301[天文地球—测绘科学与技术]