Uso e cobertura dos solos nas áreas de preservação permanente de cursos hídricos do município de Santo Ângelo - RS

Abstract

The aim of the study is to evaluate the dynamics of land use and land cover in places considered Permanent Preservation Areas related to water courses in the municipality Santo Ângelo as included in the Rural Environmental Registry. The evaluation used 4 images from the Sentinel satellite system corresponding to the years 2016, 2018, 2020 and 2022, the QuantumGIS software (QGIS) and the Semi-automatic classification plugin (SCP) routine to analyze and verify the land cover and use and the dynamics of change. To observe the dynamics of land use and cover, 3 evaluation periods were considered: 2016 to 2018, 2018 to 2020 and 2020 to 2022, a period in which the Sentinel system came into operation and there was a reduction in manpower in public agencies due to the SARS-COV19 pandemic. Using the supervised classification, it was found that forest areas cover more than 60% of the Permanent Preservation Areas declared in the Rural Environmental Registry, although there has been a reduction in their entirety; the reduction of area in the exposed soils class or with low coverage in relation to the agricultural class indicates an adoption by agricultural cultures with a longer cycle; agricultural expansion over Permanent Preservation Areas in 2020 and 2022 was not significant; and, the reduction in the water class area may have been motivated by climate change and vegetation cover dynamics. The dynamics of land use was observed by the occurrence of the conversion of forests to exposed soils or agriculture and livestock and by the occupation of forests in places previously with agricultural use.