Tropical vegetation analysis with Landsat thematic mapper and Canadiansynthetic aperture radar data,

摘要

Abstract: To test the synergy between optical and microwave remote sensing data sets for vegetation analysis, a comparison was carried out between the results of vegetation land cover classification using multitemporal landsat thematic mapper (TM) alone, and then in conjunction with a Canadian airborne C-band synthetic aperture radar (SAR) image gathered as part of the South American Radar Experiment (SAREX'92). These data sets cover the Tapajos National Forest area of the Brazilian Amazon (Para State). Occurring within the area are many land use and cover types, including extensive tracts of undistributed humid tropical forest, large pastures, small scale agriculture, abandoned plantations and secondary forest growth on old agricultural fields. The addition of radar backscatter and texture information (HH and VV polarizations) to optical data sets significantly increased the separability of classes. For instance, VV backscatter was much higher in areas of permanent agriculture versus those of smaller rotational fields. However, the complexity of the radar backscatter information requires sophisticated analytical capabilities that are only now in development. The synergistic use of active and passive sensors holds a broad promise of solving some of the analytical needs for the global change and carbon modeling communities that cannot be solved with optical data without intensive field validation and/or extensive multitemporal data sets. !11