| Oasis is the particular landscape of arid area. It is the basis of people's existence, the supporting body of economic development and the main location of people's activity. The stability of oasis has a direct relation with the development of human being. With the ceaseless exploitation and utilization, large-area land was abandoned and the NPP of vegetation descended because of salinization and secondary salinization, which heavily reduce the productivity of land and limit the development of agriculture. All of these have severely threatened the safe, the sustainable development and the inner stability of oasis.With the aid of remote sensing, combined with such factors as water resource ,climate and human being activity, this paper analyzed the dynamic change of spatial pattern of soil salinization. and it analyzed the influence of environmental factors on the dynamic change of soil salinization, So to prevent and father the secondary salinization of soil in irrigated area, to maintain the stability and safe of oasis in arid area are all of great importance.Take Sangong River Basin of Fukang as research area. The contents of this paper are as follows: Combined traditional outdoor investigation data (year 2003) with contemporaneous remote sensing image (TM), the paper classifies the soil salinization and builds a reasonable and correct interpretation way; Using the established interpretation way, dispose the data originated from TM image of 1988 and 1999;Analysis on the change of the incoming and carrying flow of surface water, groundwater level and water quality, using spatial interpolation analysis the groundwater table ,discussed the reason of soil salinization and analyzed the influence factor of pattern and dynamic change of salinization in Fukang. This paper got the following conclusions:1. By K-T transform, the information of soil salinization can be extruded, it is benefit for us to extract soil salinization information .So ,it is useful to improve the classification precision.2. Spectral Angle Mapper –SAM is an effective method for monitoring salinization soil classification, it realized the synthetize analysis of multi-wave-band image, it can extract soil information entirely.At the same time the precision and velocity can be improved. 3. salinization is the mobibilize phenomenon and process.The change of saltlization soil is ceaseless which about distributing range ,salinization extent ,and so on .The change not only exists in mutual transformation between the salinization soil but aosl exists in dynamic change between salinization and other land –use mode.4.The water table in the lower of oasis has ascend trend,which exists latent crisis of salinization, and the upper has the descend trend.5.The soil salinization in Sangong River Basin is highly sensitive to groundwater table , water quality and water allocation. The formation of salinization has a close relation with the groundwater level and mineralization degree. water allocation affect the water table and water quality in direct, at the same time arosing salinization dynamic change. Generally, the higher the groundwater, the stronger evaporating capacity of dive and more soil salic are. 6. The weather of Sangong River Basin is drought, and evaporation is strong .The main inform of ground water consume is rising and evaporation .The strong evaporation bring on the water in soil to the bad . the surface soil is addumulated salt seriously. At the same time the rain is not aboundance enough to eluviate salinity of the earth's surface .So ascend current have comparative advantage in the soil.water uprightness move is strong.Ground wate take salt in soil to the eath surface,which lead surface soil seriously accumulate salt. The more diferent between evaporation and precipitation the more the soil accumulate salt are.7.In the process of salinization occuring ,the function of hunman'disturb ing can not be ignore.The absurd land-use and water resource utilization can result in secondary salinization of soil .In...
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