Application of ERS-1 SAR data in combination with Landsat and SPOT data for forestry mapping in a Norwegian forest region

Multisensor ERS-1 SAR and optical data from Landsat and SPOT have been used for extraction of forestry parameters such as cutting class and age, for a productive forest area outside Oslo, Norway. The work approach was to study the relationships between the satellite band counts and forest stands identified by use of a digital forest map and database. The work showed that the younger cutting classes I and II could be separated from the older by using the Landsat bands 3, 4 and 5. Similar results were obtained for SPOT bands 2 and 3. None of the cutting classes could be separated from SPOT band 1. Limited statistics were available for the SAR data, but indications of that the oldest class V could be separated from the others were obtained. For the bands TM 4 and 5, and SPOT 3, also a significant correlation between satellite signal and forest age was observed for forests younger that 25-35 years