Caracterização espaço/temporal da cobertura vegetal da bacia hidrográfica do Rio Atibainha/SP.

Abstract

ABSTRACT: In the perspective of considering new ecosystems management and conservation forms, it turns necessary a detailed study of space distribution, as well as of landscape conditions temporal evolution. In this direction, the landscape ecology, linked to Geographic Information Systems (GIS) and remote sensing tools, represent important allies to analyze ecosystems impacts. Vegetation represents an important factor in ecosystems balance and, the deforestation process, obviously, generates strong environment impact. This paper presents a study of land use classification results obtained from MSS and TM Landsat multi spectral sensors extracted by the normalized difference vegetation index (NDVI) and declivity data to diagnose the space/temporal vegetation covering distribution at Atibainha/SP watershed. Results showed that it occurred an increase of vegetation cover in 16% throughout a twenty years period(1981 to 2001) as well as decrease of 13% in pasture activities. One of the hypothesis conceived to explain this results is based on the fact that pasture could be turned an economically unprofitable activity, due to an erosive processes associated to it.