Uso de geotecnologias no diagnóstico da mata ciliar do Reservatório Engenheiro Francisco Sabóia, Ibimirim - PE

Abstract

With the development of cities, disorderly occupations have grown exponentially, impacting many vegetation formations, especially riparian forests, even though they are still protected by law for being in Permanent Preservation Areas (PPAs) and presenting great importance in maintaining the quality and stability of water bodies, such as in artificial water reservoirs, which provide society with regulation and water supply, especially in regions with water scarcity, such as the Caatinga. Therefore, the present study aims to diagnose the situation of riparian forests in the PPA strip around the Engineer Francisco Sabóia Reservoir, located in the municipality of Ibimirim, in the state of Pernambuco, seeking to understand and describe the degrees of degradation and conservation, verifying their adequacy in relation to current environmental laws, in a GIS environment. Through documentary research, the absence of licensing was verified, and consequently, the corresponding PPA strip was not defined. Therefore, for the study, a measurement of 100m was considered according to CONAMA Resolution 302/2002. High-resolution images from the CEBERS 4A satellite were used. The data were manipulated in QGIS software to create thematic maps of land use and occupation, through supervised classification of five classes: water, consolidated vegetation, shrub vegetation, agriculture, exposed soil, the NDVI map to quantify the percentage of preserved and degraded riparian forest, and the slope map to understand the altimetric configuration of the region. As results, the land use and occupation map showed the presence of agricultural activity with approximately 22%, as well as approximately 9% of exposed soil, 9% of consolidated vegetation, 25% of shrub vegetation and water 35%, evidencing non-compliance with the legislation. In addition, the NDVI calculation clearly indicated the fragility of vegetation throughout the extension of the PPA, with few fragments of vegetation cover and a lot of area with dead or water-stressed vegetation. It is concluded that this diagnosis has results capable of guiding effective management with planning based on territorial planning and restoration actions of the reservoir's PPAs, providing reflections on the environmental situation of an area with such environmental, economic, and social importance for a severely degraded biome.