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Using the combined methods of digital image processing of remote sensing data, a Geographical Information System (GIS) and analysis of historical books and maps, this paper aims to contribute to a better understanding of the processes and mechanisms of land-use and land-cover changes and hydrological variations during the last 2000 years in a hyper-arid environment. The southern and eastern Taklamakan Desert, one of the driest and ecologically most sensitive regions in China and characterized by a long history of human settlements, was chosen as the study area. A hydrological connection between the Keriya and Niya rivers in former times was recognized for the first time using satellite imagery. After transferring the notes and maps of historical times into a simplified modern map, it shows that the Lop Nuer decreased in size from a large lake in the Han Dynasty (206 BC to AD 220) to a much smaller one in the Qing Dynasty (AD 1644–1911). Areas settled in former times differ morphologically from the dune landscape in satellite imagery because of flat relief along dried river courses. A review of archaeological literature reinforces the fact that in the lower reaches of the Keriya and Niya rivers, in the interior of the Taklamakan Desert, irrigated agriculture was widely practised from ca. 200 BC to ca. AD 500. A possible climatic change toward drier conditions at ca. AD 500 is suggested as the cause of the abandonment of the cities in the desert and for the initial drying of the formerly large Lop Nuer Lake. [ABSTRACT FROM AUTHOR]

Groundwater plays a critical role in arid West China where water is the limiting factor for development. This paper first describes groundwater characteristics in a region of four arid inland river watersheds and the problems associated with groundwater consumption. This region exhibits a unique alternating pattern of high mountains and depressions, which results in extensive interactions of surface water and groundwater. Then the authors propose six strategies to support adequate exploitation and use of groundwater in the region. These strategies are: 1) setting up a groundwater monitoring system; 2) forming a unified watershed authority, 3) protecting mountain ecology; 4) increasing the efficiency of groundwater usage; 5) protecting groundwater; and 6) supporting advanced research. The implementation of these strategies should be built upon the promotion of sustainable economic development and broad public support. [ABSTRACT FROM AUTHOR]

Water is a main controlling factor for economic development and eco-environmental protection in the inland river basins of arid western China. Ground-water, as a component of total water resources, plays a dominant role in the development of western China because of its stable quantity and quality. In recent years, the utilization ratio of surface water has been raised, the ground-water recharge rate from surface water has been reduced, and ground-water has been exploited on a large scale. This has led to the decline of ground-water levels and the degradation of eco-environments. Taking the Heihe river basin as an example, this paper describes ground-water characteristics in the water cycle, deals with the status of ground-water resources, analyses the problems of ground-water resource development and, finally, suggests strategies for rational use of ground-water resources in the arid inland river basins of western China. [Copyright &y& Elsevier]