Gabon’s Overlooked Carbon: A tropical forest study of coarse woody debris

Large dead trees and other large forest detritus (collectively known as coarse woody debris, or CWD) play an important role in the global carbon cycle. In tropical systems, CWD stocks (necromass) have been found to constitute 5% to 33% of total biomass. Despite harboring the second largest rain forest on earth, in Central Africa there have been virtually no studies of coarse woody debris. In this study 15 plots were established in 5 forest zones in Gabon, Africa to measure CWD stocks and potential environmental and land-use determinants of CWD. Necromass of CWD was found to be positively correlated with precipitation and was higher in logged forests than in primary forests. Extrapolated to the entire country, Gabon is estimated to contain carbon CWD content of between 0.34 Pg C to 0.72 Pg C (14 Mg C ha-1 to 30.1 Mg C ha-1). The results of this study will help improve tropical forest carbon flux estimates.