Avaliação temporal do uso da terra com imagens do satelite Landsat sensores TM e ETM+, no Município de Giruá - RS

Abstract

Maps are the best way to register and analyse by cabinet the landscape elements, and it is absolutely necessary to achieve efficacy in the planning of economic development, prioritizing the good use of natural resources. With thematic cartography it is possible to obtain specific information about some theme or phenomenon determinate, showing its localization and distribution in the geographic space. The use of remote sensing by satellite images analyse is one of the ways that is available today to accelerate and reduce mapping costs and of geo-environmental changes detection. The remote sensing techniques has been a utilization impulse in the last two decades, in view of rational natural resources use prioritization in to a continuous environmental control. With approach of high resolutions images from satellites like Landsat Thematic Mapper (TM), studies are done to access the potential techniques of digital processing images to map, monitor and plan. To researches and surveys of natural resources, the application of satellite images is today practically a indispensable resource, been used to study the environment, map and know territories, providing in a fast and precise way updated information for the natural resources management. 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 TM and ETM+ Landsat satellite, where remote sensing techniques have been applied. The studied region of Giruá has a great diversity of use and occupation, presenting an area of 85.364.7650 ha, which is located in the Northweste area of Rio Grande do Sul. It was used imagens of sensors TM and ETM+ (bands 1, 2, 3, 4, 5 and 7) from January 1997 and March 2002. Troughoust 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 SPRING, were used. The presented results show the potencial of remote sensing 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 Giruá.