Environmental Changes in a Key Region of the Pampa: A Quantitative Analysis of Land use in the Ibirapuitã Environmental Protection area (Rio Grande do Sul) and Surroundings

Objective: To analyze land use patterns in the Environmental Protection Area (APA) of Ibirapuitã (Rio Grande do Sul, RS) and surrounding municipalities between 1985 and 2022. Theoretical framework: Although the South Brazilian Pampa biome is traditionally associated with low-impact agriculture, there is a recent advance in the conversion of natural vegetation in areas of remnants of native fields such as southwestern RS. This region is home to the Ibirapuitã APA, the largest conservation unit in the Pampa biome in RS (more than 300,000 ha). Methods: Based on land use maps obtained from the MapBiomas platform, the areas of each land use class were extracted and quantified using geoprocessing techniques. We then compared the annual trajectories of land use classes in the internal perimeter of the APA and the surrounding area using descriptive statistics. Results: During the analyzed period, the areas of natural land use classes (native grassland and forest) remained stable within the APA, while in the surrounding municipalities the areas of native grasslands were markedly reduced and mostly replaced by agriculture and urbanization. Implications: The Ibirapuitã APA proved to be strategic for the conservation of native fields in this region of the southern Brazilian Pampas. Novelty: By comparing land use trajectories in the internal perimeter and surroundings of the conservation unit, this study provides the first assessment of the effectiveness of the Ibirapuitã APA in maintaining the natural vegetation of the South-Brazilian Pampa biome.