Modeling wetland vegetation using polarimetric SAR

Airborne polarimetric synthetic aperture radar (SAR) data are investigated for their potential in mapping herbaceous coastal wetlands. The subenvironments of coastal wetlands have very distinct vegetation cover and surface properties. Qualitative analysis of the SAR images reveals the relative importance of surface and vegetation scatter in these subenvironments. Furthermore, sampled SAR data distinctly separate the subenvironments, indicating that classification techniques could be used to discriminate among them. Although wetland environments are typically too vegetated to use empirical surface models to explain the SAR return, discrete scatterer models can be used to account for the scattering due to the vegetation. A discrete scatterer model fitted to a coastal wetland site on Bolivar Peninsula near Galveston, Texas provides insight into the dominant scattering mechanisms, and may aid in the accurate mapping of coastal wetlands.