Situated in the hinterland of the Qinghai Xizang Plateau, the eco environment of the source regions of the Changjiang (Yangtze) River and the Huanghe(Yellow) River are getting worse in recent years and has attracted i...Situated in the hinterland of the Qinghai Xizang Plateau, the eco environment of the source regions of the Changjiang (Yangtze) River and the Huanghe(Yellow) River are getting worse in recent years and has attracted increasing attention of researchers around the world. This paper discusses several major problems concerning the eco environment of the source regions. The authors hold that the two eco environment extents of the source region of the Changjiang River should be demarcated with the confluence of the Deng’ailongqu River to Zhidoi as its boundary, or 1.15×10 4 km 2 larger than the hydrological source area; while that of the Huanghe River should be delimited with Medotangumaxia in Darlag County as its limit, or 1.84×10 4 km 2 larger than the hydrological source area. The eco environment of the source regions with vegetation, soil, wetland, lake and river as the main elements, has always been affected by climatic changes, freeze thaw processes (including frozen soil freeze thaw processes and glacial snow cover freeze thaw processes), rodent damage and human activities. From an evaluation angle of fragile ecosystem, a study index system is established and several important issues for future research are suggested.展开更多
文摘Situated in the hinterland of the Qinghai Xizang Plateau, the eco environment of the source regions of the Changjiang (Yangtze) River and the Huanghe(Yellow) River are getting worse in recent years and has attracted increasing attention of researchers around the world. This paper discusses several major problems concerning the eco environment of the source regions. The authors hold that the two eco environment extents of the source region of the Changjiang River should be demarcated with the confluence of the Deng’ailongqu River to Zhidoi as its boundary, or 1.15×10 4 km 2 larger than the hydrological source area; while that of the Huanghe River should be delimited with Medotangumaxia in Darlag County as its limit, or 1.84×10 4 km 2 larger than the hydrological source area. The eco environment of the source regions with vegetation, soil, wetland, lake and river as the main elements, has always been affected by climatic changes, freeze thaw processes (including frozen soil freeze thaw processes and glacial snow cover freeze thaw processes), rodent damage and human activities. From an evaluation angle of fragile ecosystem, a study index system is established and several important issues for future research are suggested.