Rice field mapping and monitoring with RADARSAT data

The aim of this paper is to assess the use of RADARSAT data for rice field mapping and monitoring. The specific characteristics of RADARSAT data, i.e. the radar polarization, the spatial resolution, the range of incidence ang les and the repeat cycle, have been studied. Experimental data have been co llected over one of the most important irrigated flood plains of Indonesia and analysed along with RADARSAT data. The radar backscatter coefficient si gma degrees of rice fields appears to have a significant temporal variation . However, the dynamic range of RADARSAT data is found lower than that of t he ERS data due to a higher backscatter at HH than at VV polarization at ea rly stages. At a higher incidence angle (42 degrees compared with 23 degree s), the sigma degrees of the tine resolution F3 mode reaches a saturation l evel earlier compared with the standard resolution mode, which appears cons equently to be most appropriate for rice field mapping. The mapping result, based on the temporal change of the radar backscatter, was found to have a n accuracy of 87% compared with the available map. In order to follow the g rowing cycles and improve the management of irrigated perimeters, a methodo logy for Golongan (fields with the same irrigation scheme) mapping have als o been developed. The results appear promising and rice mapping operations using RADARSAT data can be foreseen.