Avaliação de áreas de preservação permanente a partir da caracterização da vegetação na microbacia hidrográfica da Sanga da Restinga-RS

Abstract

In the past the development of the society almost depended that totally of the agricultural section and even in the present it consists of an important activity. As the areas were increased for the agriculture were also reduced the areas of forests, this fact is visible through the observation of the terrestrial surface. With the reduction of the areas of forests if he/she had a reduction in the control of the flow and of the erosion of Microbacia Hidrográfica of Sanga of the Sandbank, this easiness to cause the increase of the flow picks and assoreamento of the bed of the courses hídricos resulting in inundations and losses of fertile soil for the erosion. This work has as main objective to identify the vegetation classes in the microbacia hidrográfica through NDVI (Index Differentiated Normalized of Vegetation) done with the images of the satellite Landsat 7, Sensor ETM+ of the year of 2000. They were established the following classes: exposed soil, I sole partially exposed, fields, vegetation arbustivas and arboreal vegetation. It was observed that there is the domain of fields following by vegetation arbustiva, soil with little vegetation, arboreal vegetation and I totally sole exposed of the class fields it was observed that in the area the predominant economical activity is the livestock following by the agriculture, however the most important class for the balance and the stability of the microbacia hidrográfica is the class of arboreal vegetation x and vegetation arbustiva, for they be class that you/they delay the effect amount of water of the rains.