Monitoring forest activities using JERS-1 spaceborne SAR in the province of Aurora, Philippines: Relationship between forest density and RADAR backscatter

Monitoring tropical forests in the Philippines, especially illegal harvesting and land clearing, can not be accomplished using optical remote sensing because of cloud cover and haze. Imaging RADAR systems provide data on forest characteristics through clouds and haze. The objective of this study was to determine the relationship between forest density and RADAR data values using JERS-1 satellite data for Aurora province.; The RADAR data were sampled for areas of various forest density, from existing vegetation maps, and slope characteristics derived from a digital elevation model. An analysis of variance was performed to test for significant differences in RADAR data values for different combinations of forest density with slope magnitude and aspect.; There are some significant differences in RADAR values among the forest density classes. However, the local topography influences the RADAR values significantly which masks some of the forest density information. Forest monitoring would be difficult to undertake using the JERS-1 SAR data alone. This study has shown that slight changes in forest density cannot be easily differentiated. It may be possible to identify land clearing activities more easily as the forest is totally removed and differences are significant between open areas and grassland areas and various forest classes.