Dinâmica da cobertura florestal em áreas de mineração no semiárido alagoano

Abstract

Mining represents one of the main economic pillars of the state of Alagoas, driving regional development and job creation. However, its expansion has caused significant environmental impacts, especially in the watersheds within the Caatinga biome – a semi-arid ecosystem of high ecological uniqueness, characterized by xeromorphic vegetation and high vulnerability to degradation. In this context, the suppression of vegetation cover, the impairment of riparian forests, and the alteration of river channels pose direct pressures on landscape stability and on the ecological processes of natural regeneration. Understanding this dynamic is, therefore, essential to support management and conservation strategies that reconcile the sustainable use of mineral resources with the maintenance of biodiversity. Given this scenario, this research aimed to analyze the environmental transformations that occurred in the river channels of the state of Alagoas between the years 2001, 2011, and 2023, considering the effects of mining on the vegetation cover and forest dynamics of the Caatinga. The methodology was based on the integrated application of remote sensing and geoprocessing techniques, using multitemporal satellite images and cartographic data. Direct influence zones were delineated using 2 km buffers around the mined areas, allowing for the spatial and temporal assessment of degradation, regeneration, and resilience patterns. Digital image processing involved supervised classification and comparative analysis of land use and land cover, enabling the quantification of landscape changes and the identification of trends in recovery or impact intensification. The results revealed a significant reduction in native vegetation in the areas surrounding the mines, associated with an increase in exposed soil and the fragmentation of riparian forests. However, the occurrence of localized processes of natural regeneration and forest recovery in isolated fragments was verified, indicating the resilience potential of the Caatinga when subjected to lower levels of anthropogenic disturbance. Spatial transformations were more pronounced in watersheds with gentle relief and shallow soils, conditions that favor surface runoff, erosion, and siltation of watercourses. This evidence reinforces the need to integrate geospatial monitoring into environmental and territorial management instruments. It is concluded that remote sensing is a strategic tool for diagnosing and monitoring environmental impacts arising from mining, enabling the generation of degradation and ecological resilience indicators. The implementation of permanent monitoring programs for Permanent Preservation Areas (APPs) and the adoption of ecological restoration practices focused on the recovery of riparian vegetation and native cover are recommended. Furthermore, it is suggested to strengthen public policies and environmental planning instruments that promote a balance between economic development, landscape conservation, and the sustainability of the Caatinga biome. It is expected that this study will contribute to the advancement of scientific knowledge and to the formulation of integrated strategies for environmental management and sustainable land use in Alagoas.