Synergies between interventions: The Cadastro Ambiental Rural (CAR) and REDD+ in the Brazilian Amazon

Deforestation in the Brazilian Amazon has declined since 2023, yet the durability of these gains depends in part on whether smallholders, who face persistent institutional and financial barriers, can comply with environmental regulations such as Brazil’s Rural Environmental Registry (Cadastro Ambiental Rural, CAR). This study provides one of the first empirical tests of whether a national regulatory instrument (CAR) and a subnational incentive-based intervention (REDD+) reinforce one another in practice for smallholders. Using panel data from CIFOR’s Global Comparative Study on REDD+ (2010, 2014, 2018), we estimate inverse-probability-weighted logistic models to assess the association between REDD+ participation and CAR uptake, and weighted fixed-effects models to examine whether forest cover trajectories differ systematically across REDD+ participants depending on subsequent CAR registration, allowing for heterogeneity by baseline forest cover. Our results indicate that REDD+ participation was associated with higher CAR uptake primarily among smallholders already engaged in REDD+ by 2014, with little evidence of additional post-2014 registration once baseline CAR status is accounted for. Neither REDD+ nor CAR alone produced consistent changes in forest cover. However, joint REDD+ and CAR participation was associated with higher forest cover in 2014 and 2018. These complementarities vary by baseline land-use conditions: large early gains occurred in high-forest landholdings, modest short-lived effects in medium-forest landholdings, and delayed but positive effects in low-forest properties. While results depend on assumptions regarding unobserved baseline CAR registration, the findings suggest that CAR registration operates as a pathway through which REDD+ may influence forest outcomes under specific land-use conditions and time frames. Overall, the study advances understanding of how regulatory and incentive-based policy mixes operate for smallholders in Amazonian conservation.