A cobertu ra da terra da bacia hidrográfica do rio Maranhão condicionada pelas unidades geomorfológicas

Abs tract. The spatial distribution of land cover shows direct relation with the relief, especially in the Cerrado. Thus, this study aimed to map land cover in the Maranhao River basin through automatic classification and establish a relation with the geomorphologic boundaries. The land cover mapping consisted of fusion transformation of Landsat 8/OLI images and proceeded a supervised and unsupervised classification according to the geomorphological unities in the basin. The processing of image fusion allowed an increase in the spatial resolution of multispectral images from 30 meters to 15 meters. From the transformed images, there were generated five classes: Vegetation, Agropastural, Construction, Bare Soil and Water. The spatial distribution of land cover classes showed that the occupation of the Maranhao basin proved to be conditioned by regional geomorphological characteristics. Palavras-chave: spatial distribution, image fusion, automatic classification, relief, distribuicao espacial, fusao de imagens, classificacao automatica, relevo 1. Int roducao A obtencao de informacoes acerca da cobertura da terra mostra-se relevante nas analises dos processos e problemas ambientais, dos quais desde a antiguidade sao realizados estudos de mapeamento da superficie terrestre para auxiliar na organizacao das sociedades (Anderson et al., 1976; Oliveira, 1988). Os mapas de cobertura da terra se configuram em instrumentos que auxiliam no ordenamento do territorio e no planejamento ambiental (Araujo filho et al., 2007) e, por sua vez, estao relacionados com o relevo (Couto Junior et. al., 2007) que e um importante aspecto para a compreensao da distribuicao espacial da cobertura da terra.