VHF-BAND SAR FOR FOREST STEM VOLUME APPLICATIONS

VHF-band SAR holds great promise for forest stem volume mapping. The paper describes a coherent scattering model and demonstrates that radar backscattering is mainly proportional to stem volume in coniferous forests. The model is also used to develop inverse methods. It is noted that a sloping ground may change the backscattering significantly and therefore needs compensation. Results of stem volume retrieval using the CARABAS-II SAR (20-90 MHz, HH-polarisation) are shown for several coniferous forests including both flat and topographic areas. The rms error is about 20 % when compared with ground truth