One of the objectives of Forest Dragon 2 project is the generation of a forest cover change map between 1990s and 2000s for Northeast China based on ERS-1/2 tandem data and ENVISAT ASAR data. For the 1990s’ map, an automatic and seasonal-adaptive retrieval of forest biomass method was used to produce a forest biomass map based on the ERS tandem interferometric coherence. The biomass map was integrated into two categories (forest and nonforest). For the 2000s’ map, an object-based classification method was developed for ASAR HH/HV images acquired on a single date. Post-classification comparison method for change detection was adopted based on the two forest/nonforest maps.