The Research Of Vegetation Spatial Pattern Of Hetian River Basin Based On "3S" Technology

The Hetian River Basin is located in the Xinjiang Tarim Basin southern fringe, the relief of Hetian River Basin is that sourth is high and north is low, the southern is an alpine region, central section is low mountain hills area. The oasis mainly distributes in the middle of the alluvial plain, extends to Tarim Basin. Winter climate is dry and frigidity, summer has little rain and high temperature. Vegetation plays an important role in improving ecologic environment, especially in the Hetian River where the ecosystem is frail. It is very important to investigate the vegetation spatial pattern of the Hetian River based on the technology of"3S".Applying the technology of"3S",based on former research achievements and experiments, taking the reaches of Hetian River as the study area, this dissertation discusses the vegetation spatial pattern, and establishes the regression model among vegetation coverage, the distance and the elevation difference. Such research methods and results provide a certain amount of advanced instruments and basic data in the research of Hetian River Basin vegetation in the future.This dissertation gets the following conclusion via researching and analyzing.1.Through the interpretation of ETM images, Come to the conclusion that the major types of vegetation is HuYang, Tamarix and other shrubs in the study area, respectively accounted for 3.05%, 0.7%, 0.12% of the total study area.2. Based on SPOT data, 1:500,000 topographical maps data ,through remote sensing images secondary classification, spatial interpolation, and spatial superposition methods,study the spatial patterns of vegetation and draw that with the increasing of the distance and the elevation difference, the vegetation coverage on the whole shows a gradually decreasing trend. If the vegetation coverage is more than 60 percent, its distribution distance from the river bank is not more than six hundred meters and the elevation difference is not more than two meters.If the distance from the river banks is over 1,000 meters or the elevation difference is more than 10 meters, the vegetation coverage is below 20 percent.3.According to the regression analysis and related analysis of vegetation coverage,the distance from the river bank and elevation difference,getting the regression models is y=1890.4x-0.6932 and y=-0.329x3+6.0045x2-33.063x+62.366,the value of R2 is 0.7124 and 0.6685 respectively and adopted a confidence level of 0.001 the significant test. we can know there is a strong Negative correlation among the three factors.This show that there is a significant interaction among the three factors.