Borneo’s intact forests have been growing and removing carbon from the atmosphere over the past 50 years, according to a study in Nature Communications this week. Until now, carbon uptake data had been lacking for tropical forests in Southeast Asia. This finding is consistent with recent estimates of forest growth in the Amazon and tropical Africa, and provides the missing evidence for a pan-tropical forest carbon sink.
Lan Qie and colleagues use data from 71 long-term plots in Borneo’s forest monitored between 1958 and 2015. The authors find that intact forests in Borneo have gained carbon in above-ground live biomass in the mean period between 1988 and 2010, with gains that are comparable to results from African and Amazonian plot networks. They show, however, that this carbon sink is vulnerable to climate and land-use changes. For example, forest fragmentation due to human activity can produce carbon emissions, thereby offsetting the sink, and the 1997-1998 El Nino drought temporarily halted the carbon uptake due to increasing tree death.
Thus, these results add to evidence suggesting that while tropical forests can help mitigate climate change caused by human activities, their vulnerability to droughts and land-use change impacts their capacity to remove carbon from the atmosphere.