Alteração da paisagem em áreas sob a influência de mineração de grande porte no norte do estado de Goiás

Abstract

The mineral extraction in Goiás is one of the economic activities of great importance for the state and, especially, for the municipalities that have it as a base. The abundance of some minerals places the state in the top positions of the Brazilian ranking of extractivism, making the interest of installing large companies in the segment grow. In the case of developments in this sector, the alteration of the landscape is inevitable, since it is necessary to remove natural areas for the exploitation of minerals, an impact that can be added to those caused by another important economic source of the municipalities of Goiás, the agricultural sector. The general objective of the research is to characterize the evolution of the mineral activity occupied by the areas in which there are large companies in the north of the state of Goiás, between 1985 and 2015, observing intervals of a decade, besides relating this change to the data Municipalities that are based on mining. Remote sensing techniques were used in conjunction with Geographic Information Systems (GIS), such as the classification of satellite images (Landsat 5 and 8), visually inspected from polygon to polygon. In this way, the use of these techniques in the study of the evolution and change of the landscape caused by the mining activity is highlighted. The economic data were obtained by the institutions that make this survey, such as the IBGE, IMB and Atlas Brazil, which provide a basis for relating the information generated by the mapping to the economic aspects of the municipalities. Few environmental reports were available at SECIMA, which made it difficult to analyze them. Since, the companies did not provide any technical report for the research. There were also field studies, as they are important to contrast the images with the observations made in the field, besides obtaining information not disclosed in the literature. Field inspections should have been carried out in all large mining companies in the north of Goiás, since the purpose was to verify the current situation of the landscape in the regions in which they are located. But, it was not possible to visit the Maracá and Votorantim Metals enterprises because they did not authorize the research in their respective areas. The results of the mapping provided a quantitative analysis of the classes generated by the classification. Through visual observations of the mappings of the mineral developments and their surroundings, it was possible to notice the modification of the landscape in each area surveyed. In addition, the economic data could indicate the influence that the mineral activity has been causing in the municipalities in which the companies are located. And although they have a high industrial mineral production and raise the PIB of the cities, it is not invested in better wages for the population in general, that is, the income of workers does not accompany the increase of the minimum wage.