| The wide range real-time soil moisture monitoring is the universally accepted a difficulty. Remote sensing technology development causes big area soil moisture real-time or determinate real-time dynamic monitoring into possible. Yellow River Delta has the very important significance to our country economy, agriculture and so on, therefore, carrying on the remote sensing soil moisture monitoring in this region can greatly enhance the economy and efficiency of soil moisture monitoring. This will offer more prompt and effective method for local government understanding the drought situation degree and distribution, thus has the vital significance to take the positive effective measure and command scientific agricultural production.In the study area the vegetation community composes solely, in the research process the article considers the vegetation spectrum characteristic, the TM5 satellite each wave band use and the OIF index at the same time to select the best wave band in vegetation information extraction, appraises the vegetation coverage by NDVI, then fully uses these factors to interpret the vegetation community distribution, thus understands soil moisture and the groundwater level regional distribution.The relation of the thermal inertia and soil moisture content is extremely close, the thermal inertia has the response to each slight change of soil moisture. Therefore, the article uses TM data of Landsat-5 satellite to explore remote sensing information model of soil moisture. Because the vegetation coverage is higher in study area, the reflection of TM image is composed by the vegetation and the soil. Regarding the size of vegetation influence reflection, propose the concept of "optics vegetation coverage" to weigh, and carry on the estimation using the remote sensing method. Extract soil moisture spectrum information using pixel decomposition method to remove the vegetation disturbance, establish TM data model of soil moisture remote sensing using soil moisture spectrum method and recurring to the regression analysis.The article considers synthetically vegetation,soil physical and chemical character and hydrological data, using all band Landsat-5 TM image, with research technique of remote sensing-mathematics-model fusion, based on investigating groundwater level,soil moisture and other assistant datum on-the-spot, establishes experimental equation of soil moisture and ground water level, proposes the remote sensing model of appraising groundwater level distribution—GLDRS model. Carry on confirmation on the spot using the GLDRS model to the study area, the result indicates that the findings conform to the reality. It thinks that using GLDRS multi-band model to monitor and appraise groundwater level distribution is feasible on the natural belts that the depth of groundwater buried is not bigger than 3m.Finally, according to several questions which exist in soil moisture remote sensing monitoring, propose the future development direction of soil moisture remote sensing monitoring.
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