Research On Model Of Groundwater Level Distribution In The Oasis And Desert Ecotone Using Remote Sensing

Groundwater is one of the most important natural resources. It is subject to seasonal and annual variations which accur as a result of changes in irrigation, drainage, drinking configurations, and other land reclamation measures. Therefore, it is Important to accelerate economic construction. and to maintain ecological balance. and sustainable development of arid, and semiarid areas in order to use and impolder groundwater resources in reason and phase. The purpose of this study is to determine the depth of?occurrence of groundwater and to evaluate the groundwater level distribution in the oasis and desert ecotone. In this research, model of groundwater level distribution using remote sensing (GLDRS) was established using Landsat-7 ETM-~- image. b~ dint of practical work and field examination data. The main point of views and conclusion of the dissertation are listed as follow: 1. Study area is the oasis and desert Ecotone. in Qira county. Xinjiang Uyghur Autonomous Region. The ecotone is a special geographical space located between the oasis and desert, a nonlinear ecological transitional belt with vegetation cover of 20%~-30% and a groundwater level of 2m~7rn. To begin with, this study has defined oasis and desert ecotone boundary on the basis of widely collected information from the study area, including environmental, sociological and economic data. Then. usine powerful image processing software PCI. classified thematic maps of the ecotone were made. 2. In establishing Mono-band ETM-r data model for remote sensing of soil water content, multi-band ETM+ data model was built in which a new concept of 揙ptical vegetation cover?is put forward to accurately estimate the amount of soil water content affected by vegetation. Spectral information of water content is extracted using the method of decomposing pixels to remove the vegetation effects. 3. Remote sensing methods of groundwater research were summarized, and on the basis of the regression analysis of data of field measured groundwater levels and soil water content, the FTM-t- data model for monitoring groundwater level at a scale of 2m?m was established using integrative means of remote sensing and mathematical modeling. 4. The results of the experimental tests of the GLDRS model in the oasis and desert ecotone of Qira county, Xinjiang Uyghur Autonomous Region are discussed. A good correspondence (correlation coefficient is 0.901) was obtained between the groundwater level at control points, where direct measurements were made, and those derived from Landsat-7 ETM-i- data. Groundwater level distribution in the whole ecotone was evaluated and presented in the form of digital thematic maps. Ill There are 6 chapters in the paper: The first chapter discusses introduction, the previous remote sensing research of water resources, and the significance of this study. The second chapter discusses the selection of the study area, gives definition of the oasis and desert ecotone in the investigated zone, and introduces the technical flow and working environment of this study. The third chapter primarily discusses the program of the image processing and classification in remote sensing, which was used to provide the results of the data processing in the research model. In the fourth chapter remote sensing model to evaluate the GWL distribution is established by monitoring of soil water...