In response to climatic conditions and imaging characteristics, Synthetic Aperture Radar (SAR) become an option to mapping and monitor tropical coastal zones. SAR R99 B, for their operational characteristics (high space resolution, incidence angle, polarization, wavelength) it presents a great potential for the recognition of tropical zone, as the coastal plain of Bragança. The analysis and interpretation of the images SAR R99 B were based on the basic elements of extraction of information of objects, area, or phenomena. To follow the evaluation of band L discriminatory capacity in the coastal atmospheres: 1) the salt marsh present tonal widths of medium to darkness due to the reflection to speculate and diffuse,
the factors that influence the intensity of the return of the electromagnetic waves are the personal micro-relief, presence of water and the vegetation. Like this, the response of the interaction of the band L, in the polarization HH, with the marsh is characterized by dark tones and the limits of the fields with the marsh are defined better, that with the polarization VV; 2) only in the polarization VV was identified to the beach of Ajuruteua, that this acted by a blackened surface, that it corresponds to the response of the interaction of the band L with the intertidal zone; 3) the coastal dunes have the same orientation of screeching of SAR R99 B during the acquisition of the images (E-W), in other words, it forms a rectum angle with the illumination direction (N-S). Like this, the dunes are very well discriminated in the band L, in both polarizations; 4) the coastal plain was individualized better in the polarization VV, in relation to the polarization HH; 5) in both polarizations, the discrimination of the old beach ridges is favored by the double-bounce effect, that provides a larger shine of these bodies in relation to the growth of mangroves; 6) the distinction of the intertidal mangrove is due to the volumetric scattering and double-bounce mechanism. This condition peculiar of answers of the interaction of the microwaves with the dossal of the marsh is responsible for a very wrinkled texture and diamond of this unit geobotanical. This behavior is observed in both polarizations; 7) the supratidal mangrove presents a similar behavior that the intertidal mangrove, however the trees of that dossal are smaller and spaced, reducing the effect couple reflection. Consequently, there is a reduction of the rugosity; 8) in the deflorested swamp, the clay soil exposed, and the answer of the sign of that flat surface is characterized in the image by the very dark ash tones in the polarizations HH and VV; 9) the re-establishment of the flow of the tides, in some areas of the deflorested mangrove has been generating new environmental conditions, that they are revitalizing that mangrove. Like this, the answer to the interaction with the microwaves is different, if compared to the others, with
wrinkled aspect with intermediate ash tones to the of the intertidal mangrove and supratidal. In terms of dispersion of the ash levels, the image in the polarization VV presents a variability of 25% larger than in HH. From way, attributing a larger capacity of identification of objectives in the polarization VV. The main parameters of the sensor that you/they influence the capacity of discrimination of the coastal atmospheres were the polarization and incidence angle. Like this, it was identified a larger number of objectives with the polarization VV. However, in the
polarization HH the limits of the atmospheres were defined better. These results demonstrated that the polarizations are complemental in the answer of the objectives in the coastal plane.
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