Tropical vegetation mapping with combined visible and SAR spaceborne data

Abstract

Within the tropics, due to high cloud cover, vegetation monitoring can only be achieved by using both visible and microwave spaceborne data. In the present study, Shuttle Imaging Radar (SIR-B) data and SPOT data acquired over central Sumatra are used in a supervised classification of vegetation. Emphasis is put on SAR data utilization. Assessment of SAR data potentialities is carried out by using (1) SIR-B imagery alone, and (2) combined SJR-B and SPOT data. The article describes the methodology developed for exploiting the SIR-B image including raw data analysis, image filtering and image classification. Finally, combined filtered SIR-B imagery and SPOT data are used jointly in a supervised classification leading to a better discrimination of surface units. These results indicate the unique capabilities of combined visible and SAR data for monitoring tropical vegetation, especially for forest/non-forest discrimination.