Combined interventions are required to reverse biodiversity and carbon losses in tropical forest frontiers

Halting deforestation and promoting restoration are at the core of biodiversity and climate strategies in tropical forest regions. Avoiding forest disturbances is also critically important but has received far less attention, and there is a lack of clarity about the cost-effectiveness of these three different interventions. We provide the first comparison of the biodiversity and carbon benefits and costs associated with each intervention, comparing observed and counterfactual outcomes based on in-depth field assessments and high-resolution remote sensing in Amazonian Brazil. Avoiding forest disturbances delivered the greatest benefits and was more cost-effective than either avoiding deforestation or restoration, with results being robust to a range of benefit and cost assumptions. However, combined interventions delivered the greatest gains and were essential to reverse biodiversity and carbon losses.