Evaluating Dynamics of Carbon Pools Resulting from Redistribution Among Biomass Components Following Wildfires in Aberdare Afromontane Forests, Kenya

Abstract

East African Afromontane Forests are among the carbon-rich ecosystems but their stability is mainly compromised due to seasonal wildfires. The objectives of the study were (1) to determine the impacts of wildfires on various carbon pools and (2) to evaluate carbon stock redistributions among biomass components after wildfires within Aberdare Afromontane Forest ranges, The study was conducted in nine sites that experienced wildfires in 2022 within two months after the fire occurrence. A total of 35 concentric plots of 15m radius distributed in high severity (12), low (9) and unburnt areas (14) were used. Our findings indicated that the mean carbon stock for all biomass components assessed changed from 96.4 tons C ha^-1 to 46.6 tons C ha^-1 due to wildfires. Most carbon stock losses were derived from litter and herbs biomass components with a combustion of 97% and 86% respectively. Further, course wood debris and dead standing trees increased with increasing wildfire severity while standing live trees and soil organic carbon decreased with increasing fire severity. Carbon redistribution from live-standing trees to dead lying and standing trees after wildfires were mainly from young small trees. This study indicates that future forest stock will have an impact on the carbon budget if urgent measures are not put in place to control and manage wildfires. The findings of this study suggest the inclusion of wildfire assessment attributes within the national forest inventory framework to assist in accounting for losses due to disturbances. Our findings can support improvement in reporting Kenya’s carbon emission factors from land use. The study recommends periodical monitoring to evaluate long-term post-fire carbon dynamics.