Granite landscapes and their relationship with Soils in the agreste paraibano region (Brazil)

This study investigates how horizontal granite outcrops shape adjacent soils in Esperança, Paraíba (Borborema Plateau, NE Brazil). Field GPS mapping of outcrops was combined with relief analysis (TOPODATA/INPE) and soil description/classification to the 2nd categorical level of WRB, supported by IBGE soil maps and geopedological cartography in QGIS. Three soil reference groups dominate: Neosols (Litholic and Regolithic) together cover ~80% of the municipality, reflecting shallow weathering mantles (<100 cm) and semi-arid controls that inhibit B-horizon formation; in more humid fronts, Cambisols transition to Red-Yellow Argisols with a thick textural B horizon. Results indicate relief modeling in granitic landscapes is morphogenesis-dominated, with frequent rock exposure and very shallow profiles (often ≤40 cm) on steep slopes. These patterns explain the mosaic of shallow, erosion-prone soils versus more evolved profiles where humidity increases.