Formal designation of Brazilian indigenous lands linked to small but consistent reductions in deforestation

Indigenous territories in Brazil have existed since the pre-European discovery of the continent. Yet, many of them remain without formal recognition by the state. While numerous studies discuss the social implications of indigenous land (IL) designation, limited empirical evidence exists regarding its role in forest conservation. To address this gap, the present study employs a quasi-experimental design and causal-inference methods to estimate the effects of formal IL designation on deforestation across Brazil and its biomes, from 1986 to 2021. Estimates indicate an average impact of -0.05% on deforestation due to the formal designation of ILs nationwide, with variations ranging from -0.21% to 0.04% across different evaluation periods and biomes. Notably, designated ILs in the Cerrado biome had the highest avoided deforestation impacts (-0.12%, on average). No evidence of deforestation leakage was observed. The findings from this study suggest that while the promotion of formal IL designation can lead to consistent reductions in deforestation, the magnitude of its effect is relatively small to be promoted on the sole basis of an effective strategy to mitigate tropical deforestation and climate change. Nevertheless, the potential positive socioeconomic impacts of formal IL designation on indigenous peoples cannot be undermined.