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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]

Abstract: Extensive research into the changing sediment load throughout the Yangtze River (Changjiang) basin has been completed over recent years, and it provides an ongoing example of how to evaluate the consequences of natural and anthropogenic impacts on sediment processing in a very large fluvial system. This paper reviews these recent studies and critically assesses their findings regarding changes in sediment yield, load (both spatial and temporal variations), grain size, and rating curves, as well as the morphodynamic response of the channel and delta. We also discuss the factors driving these changes, including climate change, soil and water conservation measures, dam construction, and sand extraction, and consider the likely future trends in sediment load. Based on a consideration of the major outcomes of, and discrepancies between, recent studies, we conclude that sediment supply, transport, mobilization, and deposition in this large river system are complicated by the heterogeneous nature of its morphology and climate, as well as the progressive intensification of human activities. Therefore, the identification and interpretation of hydrological and sedimentological changes in the Yangtze basin can be difficult, and an in-depth study of the causal mechanisms of variations in sediment load and the impacts on the Yangtze River system is urgently required. [Copyright &y& Elsevier]

Although satellite radar altimetry was developed and optimized for open oceans, it has been used to monitor variations in the level of inland water-bodies such as lakes and rivers. Here, for the first time, we have further used the altimetry-derived variation of water level for estimating the fluctuation of water storage as an addition to the present in situ water storage estimation systems to be used in remote areas and in emergency situation such as in the events flooding monitoring and for studying the effect of climate change. Lake Dongting, the second largest lake in China, influenced frequently by flooding, was, therefore, chosen to demonstrate the potential of the technique. By using the concept of an “assumed reference point”, we converted Topex/Poseidon satellite altimetry data on water level variations in Lake Dongting to “water level” data. The “water level” time-series data and in situ water storage were used to establish a rating curve. From the rating curve, we converted data on “water level” derived from seven years (1993–1999) of Topex/Poseidon data to actual water storage in Lake Dongting. The result reveals that the seasonal and annual fluctuations of water storage occurred during the 1990s with a more frequent flooding at the late 1990s' especially the flooding in whole catchment level in 1998 and 1999. The study supports the usefulness of satellite altimetry for dense and continuous monitoring of the temporal variations in water dynamic in moderate to large lakes. [ABSTRACT FROM AUTHOR]