Envisat ASAR数据在沿海防护林提取中的应用

沿海防护林的建设与生态环境和经济发展密切相关。本文以福建省漳浦县沿海防护林地区为例,利用2005年多时相、多极化的ENVISATASAR(Environmental Satellite Advanced Synthetic Aperture Radar)数据,分析了典型地物后向散射极化和时间特性。沿海防护林的后向散射随时间变化较小,VV极化能较好的体现沿海防护林的表面形态和特征,VH极化可以将水体和沿海防护林很好的区分开来,植被间的差异在HH极化中得到较好的反映。针对不同的极化组合情况,采用面向对象的方法提取沿海防护林信息,并对提取结果进行了对比分析,认为多极化的数据更有利于防护林信息的提取。

The application of Envisat ASAR data on littoral shelter forest extraction

Littoral shelter forest is closely related to the ecological environment and economic development.Taking the littoral shelter forest in Zhangpu county Fujian province as a test site,the backscatter behavior and multi-temporal characteristics of typical land cover types have been analyzed using multi-temporal and multi-polarization ENVISAT ASAR data.Littoral shelter forest has little temporal variation in backscatter.VV polarization image can better reflect the surface form and characteristics of the littoral shelter forest,VH polarization image can be used to distinguish littoral forest from water well.HH polarization image is a good discriminator for the differences among different vegetation types.Object oriented classification approach has been applied to different combination of ASAR polarized bands.With the results of the littoral shelter forest extraction analyzed,conclusion can be drawn that multi-polarization ASAR data is quite suitable for littoral shelter information extraction.