Análise temporal do uso da terra com imagens do satélite Landsat 7 sensor ETM+, no município de Santa Margarida do Sul – RS

Abstract

The coming of the remote sensing satellites has been favoring, in the last few years, the accomplishment of risings at the distance of physical and chemical variations of the terrestrial surface in extensive and inhospitable areas, favoring the mappings and the seasonal monitorings of the earth surface mainly. Man's influence over the environment has been very problematic for the preservation and conservation of the natural resources. The alterations that have been happening during the years, are of great importance for the governmental organs. In this context, this work has the purpose of presenting a temporal mapping of the use and covering of the soil through images from the ETM+ Landsat 7 satellite, where Remote Sensing and Geoprocessing techniques have been applied. The studied region of Santa Margarida do Sul has a great diversity of use and occupation, presenting an area of 94.304.94 ha, which is located in the Southwest area of Rio Grande do Sul. It was used images of sensor ETM+ (bands 1, 2, 3, 4, 5 and 7) from September 1999 and May 2000. Throughoust these images it was possible to generate thematic maps to which classification algorithms of images were applied. The dynamics of the use and the soil covering were both obtained by means of mathematical operations of the information thematic plans, where digital processing techniques of images, from the computacional Idrisi for Windows, were used. The presented results show the potential of Remote Sensing and Geoprocessing techniques in the mapping of earth use. The obtained results are good to support a great diversity of research attempts, such as territorial planning, economic development and environmental preservation in the area of Santa Margarida do Sul.