Análise espaço-temporal de ocupação do solo na área de influência da PA-458, zona costeira no município de Bragança-PA

Abstract

This work aimed to evaluate the effects of the opening of the PA-458 highway, located in the municipality of Bragança, a coastal zone in Pará. For this purpose, images from the Landsat 5 and Landsat 8 satellites (orbit / point 222/61), from the Green bands were used; the Red; Near Infrared; SWIR 1 and SWIR 2. The choice of the time series was determined using the Google Earth Engine platform, thus defining the years of analysis, 1988, 2001, 2005, 2015 and 2020. Subsequently, using the Qgis 3.16.3 software, if the Area of Direct Influence (AID). Then, the supervised classification of the area of direct influence was carried out, having the areas identified in the classes of anthropized area, dense vegetation, less dense vegetation, natural fields, hydrography. The mathematical calculations and generated tables were made using Excel software. In addition to all these procedures, a field visit was carried out, on April 4, 2021, to identify the mapped classes and resolve doubts generated during the process. The results obtained showed that the greatest changes occurred between 2005 and 2015, with emphasis on the anthropized areas (5.7%) and a decrease in less dense vegetation (2.8%). In addition, there was an increase in anthropic action on the areas of less dense vegetation in the PA-458 AID, it was found that the area within the RESEX Marinha Caeté-Taperaçu conservation unit remained with the dense vegetation practically unchanged, only an area was observed on the right side of the highway, which suffered degradation with the opening of the PA-458 and remains with the degradation for the 32 years analyzed. As a result of this dynamic, the degraded mangrove area was found during the field visit, due to the opening of the highway. Thus, it was concluded that the use of GIS tools proved to be satisfactory insofar as it was possible to observe changes in the modes of land occupation.