Modeling of radar responses to forest physical parameters

The objective of the study was to investigate the relationship between radar response and forest parameters, i.e. stem density, tree height and biomass. Field measurements of trees and the underlying soil surface of a conifer forest stand were used in modeling of radar backscattering from 100 simulated forest stands with average tree height and stem density randomly generated within specified ranges (height from 2 to 20 meters, stem density from 10 to 3400 trees/ha). The modeling results were also compared with measured backscatter from stands in Maine, USA. The results show that radar return is more sensitive to tree height than to stem density. The total biomass has much higher correlation to the radar return than to tree height or stem density alone. Modeling results also show that the cross-polarization return at a longer wavelength has the best correlation with forest physical parameters