The Study On Spatial Heterogeneity Of Soil Water And Salinity In Oasis And Transition Between Oasis And Desert Of Zhangye City

The oasis is the special view type of integration of nature and humanity in arid region, while it is also the quintessence of the arid region. But when the oasis environment worsens and closes to disintegrate day by day, according to support various kinds of key elements on the human survival foundation to tend towards disintegrating, the human society will be unable to hold. In arid region, water is the basic condition of oasis shape and development and the blood of oasis agricultural production. Oasis agriculture must rely on irrigating. But if irrigating is unreasonable, it can cause wasting and shortage of water resource and soil salinization etc., and the deterioration of the ecological environment in the oasis finally. And a transition zone between oasis and desert is an ecologically vulnerable zone, a key factor to threat oasis stability, and a general area that often take place soil salinization. So study on spatial heterogeneity of soil water and salinity in oasis and a transition zone can provide certain scientific directions for sustainable development in arid region. But the domestic and international study on this respect is concentrated on qualitative analysis and research mainly at present, little to quantitative analysis and research.Zhangye City locates in the Hexi Corridor midsection, is typical arid area, has obvious view of oasis and desert, and exists of serious water resource shortage and soil salinization problems. So this thesis regards Zhangye City as study area, and quantificationally analyzes and researches spatial heterogeneity of soil water and salinity in oasis and a transition zone.The thesis includes five chapters.Chapter 1 mainly introduces the background of the selected title, study meaning, geostatisticsal research status quo in soil spatial heterogeneity and study area choice.Chapter 2 explains physical geographical conditions of study area and research methods that include sampling methods, experiment methods, and data processing methods that make up of semivariance and kriging in geostatistics and are introduced mainly.Chapter 3 mainly analyzes and compares statistical and geostatistical characteristics of different physiognomy positions, landscape types and soil layers about soil water and salinity located in a transition zone between oasis and desert in north and south direction. Then it progresses relativity analysis and compare of soil water and salinity of different physiognomy positions and soil layers.Chapter 4 mainly analyzes statistical and geostatistical characteristics of soil water in oasis area. About geostatistical characteristics, firstly the thesis compresses analysis from the isotropy and anisotropy, then combined analysis results and utilized inserting value of kriging, makes pattern map of space distribution of soil water of different soil layers, and finally calculates area and proportion of soil water of different grades.Chapter 5 summarizes central conclusion of the thesis, while it puts forward the future research direction that need to improve and strengthen.