Detecting and mapping flotant using synthetic aperture radar data

Floating marshes (flotant) are widely distributed in coastal Louisiana and have been studied for many years. Enhanced backscatter can be a useful tool in detecting and mapping flotant on synthetic aperture radar (SAR) data. Ormsby et al. (1985) noted an enhanced return from flooded forests on L-band SAR imagery and from flooded marsh grasses on X-band SAR imagery. The L-band wavelength is capable of penetrating the forest canopy allowing the water surface and tree trunks to act as a corner reflector providing an enhanced return signal. In flooded marsh grasses, the L-band wavelength is reflected. However, the X-band wavelength shows an enhanced return from the water surface and grass stem acting as a corner reflector. X-band SAR is the optimum wavelength for detecting the type of flooded vegetation in coastal marshes. The acquisition of X-band SAR and the completed mapping of flotant in the Barataria Basin of coastal Louisiana allows the critical evaluation of this radar data set for the detection and mapping of flotant throughout the coastal zone of Louisiana.