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The environmental information system is a thematic analysis subsystem in the water redistribution management system for the Tarim River Basin.This paper studies mainly the general design,structure and functions of the thematic analysis subsystem and the integration with other subsystems.Firstly,the ecological quality indices(EQI),such as the biological abundance index,vegetation coverage index,hydrographic net density index,land degradation index and pollution load index,are used to investigate the environmental quality in the Tarim River Basin.Secondly,a quota method is put forward for calculating the ecological water demand of natural vegetation.Thirdly,some indexes including the ecological degeneration index,risk degree index and regeneration degree index are calculated based on the concept of ecological risk assessment and the method of landscape ecology,and the corresponding ecological risk is analyzed and assessed.The results show that it is of the obvious practicality and maneuverability to take the means of ArcGIS+Oracle9i+ArcSDE to develop the environmental information system.The study results can be used to carry out the thematic assessment and analysis of ecological environment in arid areas,and can also be referred in developing other systems concerned.

Spaceborne polarimetric microwave correlation radiometer is a new type of instrument for the passive microwave remote sensing from space, which can provide an important way for remote sensing of sea surface wind vector and other ocean atmosphere environmental parameters. Antenna cross-polarization correction is an important part of the data pre-processing algorithm. In this paper, for the demand of antenna cross-polarization correction in spaceborne polarimetric microwave correlation radiometer, we have independently derived the full polarization antenna temperature equation based on the polarization coherent detection theory and the definition of Stokes parameters. The equation for the four parameters of Stokes antenna temperature introduced the cross polarization amplitude and phase between the Stokes parameters. Besides, the influence of the polarization rotation angle on the antenna pattern computation was considered. Finally, we established a geometric correspondence between the antenna scanning beam and the earth scene. The principle for determining the parameters of the antenna temperature equation was also discussed. Stokes antenna temperature equation laid the foundation for antenna cross-polarization correction for spaceborne polarimetric microwave correlation radiometer in the future.