A model relating VHF-band backscatter to stem volume of coniferous boreal forest

A physical model is presented describing the backscatter from coniferous boreal forests in the lower VHF-band in terms of stem volume. By using measurements of mean amplitude in high-resolution SAR images (rather than intensity), a linear dependence on stem volume can be obtained. The model fits well with the measurements made using the coherent all radio band sensing (CARABAS) SAR in the southern boreal forest, indicating the possibility of retrieving stem volume, and hence biomass, with an accuracy similar to that reached by standard ground-based measurements. No saturation of the scattering is seen up to biomasses of 550 m/sup 3//ha.