Análise multitemporal da arborização em cidades do Semiárido da Paraíba.

Abstract

Green infrastructure is part of the essential elements present in the urban environment and is demonstrated as one of the main components capable of making cities more inclusive and sustainable, through the benefits provided by it, such as improving air quality, mitigating the effects on climate and increasing the quality of life of residents. Therefore, the monitoring of afforestation in space-time, allows to provide models that can assist municipal managers in planning cities, especially from the perspective of urban afforestation. The objective of this study was to evaluate the changes in the arboreal component in cities of the sertão of Paraiba for the years 2016 and 2021, as well as a diagnosis of the current situation of urban afforestation through the use of satellite images and the application of geoprocessing techniques. The study was conducted in cities of the semi-arid region of Paraiba, where the urban perimeter of the municipalities of Patos, Quixaba, Santa Terezinha, São José de Espinharas and São José do Bonfim were selected. Sentinel-2A satellite images for the years 2016 and 2021 were downloaded, and then pre-processed for atmospheric corrections, clipping of the urban perimeter delimited by the research and reprojection of the images. In the image processing phase, the Normalized Difference Vegetation Index-NDVI was applied for the two periods analyzed and followed with the color composition and reclassification of the index for estimates of land use classes focused on vegetation. The second step consisted in performing the analysis of the current land cover situation through the i-tree tool where random points were assigned and these were evaluated and classified according to their type of cover. The estimates made indicated that the city of Patos presented between the space-time of five years the highest percentage of change regarding the use and coverage of the land back to vegetation when compared to the other municipalities evaluated, and it was found that the city of São José do Bonfim according to the i-tree canopy report as the municipality with the highest percentage of urban green compared to the others. Therefore, it is concluded that the NDVI presented changes in land use and land cover between the space-time of five years for all municipalities evaluated, in which the class that represents the urban green increased in all cities for the year 2021 compared to 2016. According to the i-tree canopy report São José do Bonfim showed the highest percentages of urban greenery and highest removals of air pollutants. The i-tree platform proved to be an excellent tool to be used by municipal managers to estimate the amounts of air pollutants removed annually in each municipality.