Land-use transitions and carbon emissions of aquaculture expansion in the Brazilian Amazon.

Abstract

Accounting for land-use change underlying food sector expansion is critical for conserving ecosystem integrity. This challenge is particularly acute in the Amazon, where the conversion of forests for food production is pronounced and has broad implications for global biodiversity and the cycling of water and carbon. Here, we analyze land-use transitions associated with aquaculture development in the Brazilian Amazon. We found that a 450-fold increase in aquaculture pond area from 1985 to 2022 occurred primarily on pasturelands (87%) but also included wetland conversion (4%) and deforestation (5%). Notably, continued growth can be sustained within already altered landscapes: In Rondônia, the leading aquaculture state in the Amazon, production could double by converting only 1.2% of the total degraded pasture area. While directing aquaculture expansion toward degraded pastures could reduce further natural habitat conversion and carbon costs historically associated with food production in the Amazon, realizing this potential will depend on strong governance and enforceable land-use policies to guide siting decisions.