Monitoring of deforestation and land use in Indonesia with multitemporal ERS data

The ESA ERS1-pilot project PP3-D11 was aimed at investigating the capabilities of the ERS-1/2 satellites for continuous land use and deforestation monitoring over a period of 5 years (1993-1997) in a tropical rain forest environment. Deploying texture analysis techniques, several land use classes and different forest types could be identified in single ERS-1/2 Synthetic Aperture Radar (SAR) images. The texture features created allowed the discrimination of (1) undisturbed forest of at least two different types, (2) shifting cultivation and agriculture, (3) secondary forest, (4) selectively logged forest, (5) clearings by fire and clearcutting, and (6) settlements and major roads. The results of multitemporal data analysis showed that changes in area of classes (2), (4) and (5) can be readily detected in a multitemporal sequence of ERS SAR images. KFA1000 photographs from the Russian MIR Space Station, Landsat Thematic Mapper (TM) images and ground data acquired during two extensive field excursions served as a reference for the interpretation of the ERS images. All evaluation procedures were performed with standard computer equipment and commercial software packages to ensure operationality and technology transfer towards Indonesia. The results suggest that the European radar satellites ERS-1/2 can be used to monitor and analyse forest conversion and land use patterns in tropical rain forests at scales 1 : 100 000.