Tropical vegetation analysis with Landsat thematic mapper and Canadian synthetic aperture radar data

摘要

Abstract: To test the synergy between optical and microwaveremote sensing data sets for vegetation analysis, acomparison was carried out between the results ofvegetation land cover classification usingmultitemporal landsat thematic mapper (TM) alone, andthen in conjunction with a Canadian airborne C-bandsynthetic aperture radar (SAR) image gathered as partof the South American Radar Experiment (SAREX'92).These data sets cover the Tapajos National Forest areaof the Brazilian Amazon (Para State). Occurring withinthe area are many land use and cover types, includingextensive tracts of undistributed humid tropicalforest, large pastures, small scale agriculture,abandoned plantations and secondary forest growth onold agricultural fields. The addition of radarbackscatter and texture information (HH and VVpolarizations) to optical data sets significantlyincreased the separability of classes. For instance, VVbackscatter was much higher in areas of permanentagriculture versus those of smaller rotational fields.However, the complexity of the radar backscatterinformation requires sophisticated analyticalcapabilities that are only now in development. Thesynergistic use of active and passive sensors holds abroad promise of solving some of the analytical needsfor the global change and carbon modeling communitiesthat cannot be solved with optical data withoutintensive field validation and/or extensivemultitemporal data sets. !11