Utilização do software “R” na avaliação da cobertura vegetal da bacia hidrográfica do Rio Sucuru.

Abstract

Currently, remote sensing has become an excellent tool to evaluate environmental degradation. In this occasion, present research proposes to use Software "R" to evaluate vegetation cover in the watershed of Rio Sucuru, state of Paraíba, by means of different vegetations indices. Processing of images and estimates of vegetation index (VI) were performed in Software "R", adopting specific packages and mathematical routines that denot required VI, such as: Normalized Difference of Vegetation Index (NDVI), Normalized Difference Water Index (NDWI) and Soil Adjusted Vegetation Index (SAVI). According to results, IVDN for dry period ranged from -0.3 to 0.4, characterizing, respectively, as exposed soil and presence of superficial vegetation, while for humid period IVDN ranged from 0.0 to -1.0, being, respectively, classified as threshold and watercourses and/or water. NDWI for dry period ranged from1.0 to 0.6 and for humid period ranged from -0.8 to 0.6, indicating as an area of exposed soil and with presence of agricultural areas or water courses, respectively. SAVI ranged from 0.5 to -0.8 for dry period, while for humid season SAVI ranged from 0.5 to -0.5 and were therefore characterized for two periods under study as dense vegetation and areas of high degradation. However, it is noteworthy that production of these maps was extremely fast when compared to traditional method.