Land Use and Land Cover Stability Across Protection Regimes in a Tropical River Basin.

Tropical frontiers are undergoing rapid land transformations that threaten biodiversity and ecosystem resilience. Using annual land use and land cover (LULC) data from 1985 to 2022 derived from MapBiomas Collection 8, we assessed cumulative landscape stability across three legally defined protection levels in the Araguaia River Basin, a major South American agricultural frontier. Over the study period, unprotected areas experienced the largest net losses of Natural Forest and Savanna and the lowest landscape stability, with less than 50% of the area remaining unchanged. In contrast, fully protected areas showed the highest stability, with more than 80% of their area presenting zero accumulated transitions. Sustainable use areas displayed intermediate dynamics. Environmental degradation transitions were consistently more frequent in unprotected zones, whereas restoration transitions were spatially heterogeneous and co-occurred with degradation hotspots. These results indicate that landscape dynamics differ markedly across protection categories, reflecting distinct long-term land-use spatial patterns. By providing a spatially explicit cumulative assessment over nearly four decades, this study offers descriptive evidence relevant to conservation planning and land management in rapidly transforming tropical frontiers.