Controls over aboveground forest carbon density on Barro Colorado Island, Panama

Abstract

Despite the importance of tropical forests to the global carbon cycle, ecological controls over landscape-level variation in live aboveground carbon density (ACD) in tropical forests are poorly understood. Here, we conducted a spatially comprehensive analysis of ACD variation for a continental tropical forest - Barro Colorado Island, Panama (BCI) - and tested site factors that may control such variation. We mapped ACD over 1256 ha of BCI using airborne Light Detection and Ranging (LiDAR), which was well-correlated with ground-based measurements of ACD in Panamanian forests of various ages (r(2) = 0.84, RMSE = 17MgCha(-1), P 400 years old). If other regions of relatively old tropical secondary forests also store less carbon aboveground than primary forests, the effects on the global carbon cycle could be substantial and difficult to detect with traditional satellite monitoring.