ìndice de qualidade ambiental na cidade de Montes Claros - MG

Abstract

The process of growth in the city of Montes Claros, Brazil, occurred without proper concern for adequate environmental and urban planning. This contributed to the development of a city with low vegetation indices, scarcity of green areas, thermal imbalance, and higher surface temperatures in low-income neighborhoods. These factors directly interfere with urban environmental quality, which is an important indicator of city sustainability, associated with the well-being and quality of life of the population. Therefore, the aim of this research was to generate an Urban Environmental Quality Index (UEQI) for Montes Claros, Brazil, using geotechnologies and their applications through Remote Sensing, based on the following environmental indicators: Surface Temperature (ST), Normalized Difference Vegetation Index (NDVI), Normalized Difference Built-Up Index (NDBI), green areas, and building density. These indicators were generated and organized within a Geographic Information System (GIS) environment. Firstly, density rasters of buildings and green areas in Montes Claros were generated using the Kernel method. Secondly, vegetation indices (NDVI and NDBI) and ST were generated. To obtain the UEQI, the urban environmental quality indicators were reclassified using weighted values as follows: 1 - Very High Quality, 2 - High Quality, 3 - Medium Quality, 4 - Low Quality, and 5 - Very Low Quality. In this case, all variables had five value intervals, except for the green area variable, which had two intervals: 1 and 5, to indicate the presence or absence of green areas. The final map had four classes: Very High (15%), High (34%), Medium (39%), and Low (12%) quality. Overall, the UEQI showed that the highest concentration of very high environmental quality is present in the southwest portion of Montes Claros, where the highest NDVI values (> 0.50), low building density, higher concentration of green areas, and lower temperatures (22 – 24°C) were observed. On the other hand, areas with poor urban environmental quality recorded temperatures above 30°C, low levels of vegetation and green areas, and high building density. The results demonstrated that urban environmental quality is closely related to the presence of vegetation in urban areas, particularly due to its key role in thermal control, which is crucial for the well-being of the population. In this sense, this study reveals, through geospatial products, the hotspots of low urban environmental quality in Montes Claros, serving as a fundamental tool for decision-makers, especially aiming to improve the environmental quality for the population. Finally, it is expected that the achieved results will be useful for the public administration of Montes Claros.