Estimation of forest biomass and soil moisture in boreal forests employing ERS-1 SAR data

The results obtained in the retrieval of forest stem volume (forest biomass) and soil moisture using multi-temporal ERS-1 SAR data are presented. A novel inversion method for interpreting the ERS-1 SAR data is employed. The method is tested in conditions of Finland. The inversion technique is based on the use of (1) multi-temporal ERS-1 SAR data, (2) reference sample plot information and (3) a semi-empirical forest backscattering model. It is shown that multi-temporal ERS-1 SAR images can be successfully used for estimating the forest stem volume. The effect of soil moisture has been analyzed using hydrological soil moisture model-based results as a reference. The results indicate that the soil moisture of a forest area can be determined from an ERS-1 image.