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Zhangye City in Gansu Province, western, middle of Hexi Corridor, the middle reaches of the Heihe River Basin Strip, is a typical arid inland oasis landscape. Zhangye City is very rich in agricultural resources, rich in wheat, corn, rice, canola, flax and other crops, the country's major grain production bases and the famous Western cuisine DONGYUN base. In recent years, due to population pressure of rapid economic growth, the obvious contradiction between the soil and water resources, the irrational exploitation and utilization of natural resources, ecological environment is very fragile oasis - desert ecotone appears such as land desertification, desertification, salinization based on the serious problems of the oasis ecological space stability. The papers choose Zhangye Oasis edge three typical oasis - desert ecotone as a pilot area, soil samples, experiments on seven kinds of soil characteristics (soil moisture content, respectively, of a water-soluble salt content, pH, mechanical, bulk density, available phosphorus content, hydrolyzed nitrogen content). First, according to the analysis of soil properties derived value, summed up the law of its spatial variability, and then use the The variogram map description oasis - desert transitional space of the soil characteristics and spatial correlation distance; then combined with the specific circumstances of the test area and soil science knowledge, analysis of the reasons that affect soil spatial variability and its relationship with the the oasis ecological space stability. The structure of the thesis: The first chapter describes the theoretical basis of the research work; second chapter describes an overview of the study area and sampling and experimental methods; Chapter is the core of the paper, the use of intuitive icons and semivariogram described two ways a preliminary analysis and summary of the law of the spatial variability of soil properties; Chapter is another focus of the paper, land statistical interpolation method to complete the forecast value of the surface soil characteristics of the test area; Chapter is the ultimate significance of the papers where, try to understand the spatial patterns of soil characteristics the oasis ecological stability of the space; summarized in the sixth chapter of the thesis research and inadequacies. Through the study concludes that a different sampling scales (100m, 300m and 500m) Oasis the - desert transitional soil characteristics, levels of Variation and vertical Variation; desert ecotone soil characteristics by analyzing oasis - Variation of the oasis ecological space stability on the relationship between the oasis - desert ecotone common feature of soil degradation: drought in the 1000m scale soil environment; coarse graining of soil particles on the scale of 500-900m; in multiscale ( available phosphorus 230m; hydrolysis nitrogen 4000m) on Soil Nutrient Depletion. The ultimate goal is the entry point through the soil more in-depth understanding of the mechanism of oasis - desert transitional soil desertification, desertification, salinization and other issues and prevention, so as to contribute to the protection of the the oasis ecological space stability.
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