Land cover changes in buffer zones and the effectiveness of this conservation strategy: Case study of Southeastern Brazil

Although buffer zones have been established around protected areas as an effective strategy to minimize human impacts on significant conservation areas, considerable challenges remain in managing these zones, including frequent disregard for their management rules. The objective of this study was to analyze the land cover changes that took place from 1985 to 2022 around 25 conservation units in São Paulo State (Brazil). The methodological process consists of two stages: (1) Identifying and analyzing land cover changes in the buffer zones and external zones adjacent to these zones; and (2) Evaluating the effectiveness of the buffer zones and comparison of the changes observed in buffer zones and external zones. The results demonstrated that land cover changes in the buffer zones and external zones generally behave similarly in the studied conservation units and are positively correlated, meaning they tend to move in the same direction. This behavior is counterintuitive to what was expected for the buffer zones. Greater São Paulo and its surroundings, as well as the central-eastern region of the state, showed a higher concentration of conservation units with a tendency for natural habitat loss in both zones (buffer and external zones). In contrast, regions such as the Vale do Ribeira and Paranapanema, as well as Pantaninho Paulista, showed a tendency for natural habitat gain in these zones. It is hoped that the information imparted by this study can be utilized by managers in the decision-making process, aiming for more targeted and successful management of protected areas and their surroundings.