Radarsat backscattering from an agricultural scene

Orbital remote sensing in the microwave electromagnetic region has been pre sented as an important tool for agriculture monitoring. The satellite syste ms in operation have almost all-weather capability and high spatial resolut ion, which are features appropriated for agriculture. However, for full exp loration of these data, an understanding of the relationships between the c haracteristics of each system and agricultural targets is necessary. This p aper describes the behavior of backscattering coefficient (sigma (o)) deriv ed from calibrated data of Radarsat images from an agricultural area. It is shown that in a dispersion diagram of cr there are three main regions in w hich most of the fields can be classified. The first one is characterized b y low backscattering values, with pastures and bare soils; the second one h as intermediate backscattering coefficients and comprises well grown crops mainly; and a third one, with high backscattering coefficients, in which th ere are fields with strong structures causing a kind of double bounce effec t. The results of this research indicate that the use of Radarsat images is optimized when a multitemporal analysis is done making the best use of the agricultural calendar and of the dynamics of different cultures.