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The source region of the Yangtze River is in the hinterland of the Qinghai-Tibet Plateau. The source region is of great ecological significance to Qinghai-Tibet Plateau, and it is praised as the resources bank of biological species. The ecological environment in the source region of Yangtze River has deteriorated during the past decades. Based on land ecological classification and field investigation, two-phase Landsat TM/ ETM remote sensing data obtained in 1995 and 2010 were compared. The spatial changes and dynamic transfers of land ecotypes in the source region were analysed in this paper by using the analytical methods. Results show that the environmental problems in the source region have been caused by the global climate changes and human activities, coupled with the harsh natural conditions and a fragile ecological system. These changes also affect the water environment and the social-economic development of the river basins. There is an urgent need to study possible rehabilitation measures for the eco-environment of the region so as to ensure a sustainable larger river discharge. [ABSTRACT FROM AUTHOR]

Induced by high population density, rapid but uneven economic growth, and historic resource exploitation, China’s upper Yangtze basin has witnessed remarkable changes in land use and cover, which have resulted in severe environmental consequences, such as flooding, soil erosion, and habitat loss. This article examines the causes of land use and land cover change (LUCC) along the Jinsha River, one primary section of the upper Yangtze, aiming to better understand the human impact on the dynamic LUCC process and to support necessary policy actions for more sustainable land use and environmental protection. Using a repeated cross-sectional dataset covering 31 counties over four time periods from 1975 to 2000, we develop a fractional logit model to empirically determine the effects of socioeconomic and institutional factors on changes for cropland, forestland, and grassland. It is shown that population expansion, food self-sufficiency, and better market access drove cropland expansion, while industrial development contributed significantly to the increase of forestland and the decrease of other land uses. Similarly, stable tenure had a positive effect on forest protection. Moreover, past land use decisions were less significantly influenced by distorted market signals. We believe that these and other findings carry important policy implications. [ABSTRACT FROM AUTHOR]

Land use/cover change (LUCC), which results from the complex interaction of social, ecological and geophysical processes, is a major issue and the main cause of global environmental change. This study analyzed the land use/cover dynamics and their environmental and socio-political forces in the upper reaches of the Yangtze River from 1980 to 2000 by using remote sensing, climatic and socio-economic data from both research institutes and government departments. The results indicated that there had been significant land use/cover changes between 1980 and 2000 in the study area, which were characterized by a severe replacement of cropland and woodland with grassland and builtup land. The transition matrices highlight the dominant dynamic events and the internal conversions between land use/cover types during the study period and reveal two distinct transition phases. Land use/cover changes in the upper reaches of the Yangtze River during 1980 to 2000, while restricted by environmental attributes, were strongly driven by socio-political factors. However, excessively pursuing higher land use benefits likely results in serious environmental degradation. This study suggests that the restructuring of land use should be based on land suitability and sustainable protection of fragile environment in the upper reaches of the Yangtze River. A thorough comprehension of historical changes will enhance our capability to predict future land use change and contribute to effective management strategies and policies for the rational land use. [ABSTRACT FROM AUTHOR]