Análise das áreas de preservação permanente na bacia hidrográfica do arroio cambaí, Itaqui, RS

Abstract

Remote sensing is one of the best technologies for obtaining images from a distance over the earth's surface, thus being able to automatically collect data for surveying and monitoring earth resources on a global scale. Due to the advancement of imaging technologies through sensors attached to satellites, especially in the last four decades, there has been an increase in technologies that use sensors placed on board aircraft or satellites in Earth orbit to obtain the reflectance of electromagnetic radiation reflected by objects on the surface, with the electromagnetic radiation emitted by the sun as the main source of energy. According to Law no 12.651, of May 25, 2012, a Permanent Preservation Area - APP means the entire sheltered area, covered or not by native vegetation, with the environmental objective of protecting water resources, the landscape, the stability geology, biodiversity, the migration of fauna and flora, protect the soil and ensure the well-being of human populations. The study of changes in the geometric constituents of the landscape is essential for nvironmental studies. The disappearance or appearance of new spatial arrangements in the landscape can cause significant ecological effects, such as changing the types and variety of habitats, changing the spatial organization of specimens, nutrients and the passage of organisms. The area selected for the study is the Cambaí stream watershed, located in the municipality of Itaqui, RS, as can be seen in Figure 1. The research presents a way of monitoring riparian forests through vectorization of satellite images. With the present study, it was possible to identify that in the area in question there are less than 50% of the APPs preserved, considering the parameters of the Forestry Code. It should be mentioned that the satellite images used are an important instrument for the environmental analysis of smaller areas, considering their spatial resolution, in addition to being free of charge, which allows access and low-cost monitoring.