| This paper studied the Oases succession process for the past 50 years in Manas river basin of the biggest agricultural district in Xinjiang. On the basis of analysis of ecological environment, structure, function and productivity, the direction and key techniques for the sustainable development of Oases agriculture were put forward.The use of water resources for Oases in Manas river valley have experienced from large scale surface water exploration stage to surface water & groundwater development stage and then to the high efficiency and economical stage. The use of farmland soil can be separated into four stages in order: large-scale reclamation, large-scale abandoning, recovery and reconstruction and reclamation. The changing of ecological environment can be summed up the following respects: the artificial oases replacing the natural one, the artificial oases replacing the hungrinesstification (desertification and salinization) and desertificati on replacing Oasesization. Farmlands in Oases have been enlarging constantly in the recent years, but at the same time the salinization areas also increases. Oasesization and desertification are always the two major aspects of succession in this region. Regional climatic condition has become warmer and wetter. The gap of humidity, temperature between years, wind-force and the days of dust and sand have reduced, and microclimate are toward to suitable for agriculture development and mankind living.The structure of oases agro-ecosystem was not sound for the agriculture development and the structure showed in simpliness. However, productivity and economy are still increasing with technologies such as good variety, planting pattern, field fertilization, which compensate the shortcomings of the simple agriculture structure. The stability index of Oases agro-ecosystem ranged from 0.4527 to 0.5819, a middle standard level partly lower. The order sorted in oases stability are alluvial-plain oases, alluvial-fan oases, delta oasis.The exploitation of water and soil resources is always the core problem of oases agriculture development. With the analysis of the utilization of water and soil resources and the process of recovery and reconstruction of abandoned field, some tactics for the utilization of soil and water resources were put forward. The exploitation of water and soil resources should change the traditional way tracing to the source along river to developing from downstream and lower basin in future. That is to say, in the alluvial and flood plain, some high techniques such as high efficient water-saving, well irrigation and draining, vegetation rebuilding techniques, should be practiced to recover and reconstruct the abandoned land and also should pay more attention to avoid abandoning the land that reclaimed newly. In delta area located the lowest reach and the area of the desert edge, the technique of high efficiency water-saving should be used to enlarge farmland area, for example, trickle irrigationunder-film for special crops. In bitter end, develop wood and paper integrally through the water diversions.This paper also discussed the coupled mechanism among mountain, oases and desert in mountain-basin system with the analysis of energy-flow, substance-flow and money-flow. The warm effect of desert to the oases is the main reason for the rich heat resource of the oases and affects oases agriculture. To improve the whole system economic value, the desert warm effects should be used for oases agriculture. And also, 4 kinds of patterns of agriculture and animal husbandry should be practice in mountain and oases area to increase the economic value. The soil and water resources are the important tie of mountain, oases and desert matter flow. Characteristic of differentiation was exited in mountain-basin system and agriculture development should follow this rule.This research also confirmed the function of mountain, oases and desert system and analyzed the direction of agricultural sustainable development of the oases. The mode of soil and water resour...
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