Tree diversity, carbon stocks, and land cover change of the Lwampango relict forest in the Kaziba chiefdom, South Kivu region, Eastern DR Congo

Abstract

The mountain forests are diversified and store large quantities of carbon despite the threats they face. This study highlights the relationships between tree diversity, carbon stock, and the Lwampango relict forest changes from 1990 to 2021. The inventory of tree species with diameters greater than or equal to 10 cm was carried out in 24 plots of 20x20m each. The allometric equation was used to estimate above-ground biomass. A mapping approach coupled with remote sensing was used to quantify the land cover of the Lwampango relict forest. A total of 1032 individuals, divided into 22 tree species, were inventoried. Macaranga kilimandscharica, Maesa lanceolata, Hagenia abyssinica and Polyscias fulva make up the group of ecologically significant species. The amount of carbon stored by the forest is estimated at 136.3 tonnes/ha.  Over its entire surface area, the Lwampango forest has an estimated stock potential of 25317.5 tonnes of carbon and 92915.07 tonnes of sequestered Carbon dioxide. Dense vegetation, which occupied 83.4% in 1990, fell to 73.8% in 2002, then to 71% in 2011, and finally to 78.6% in 2021. Analysis of the changes by decade shows that from 1990 to 2011, dense vegetation in the Lwampango forest declined. This regression was mainly caused by anthropogenic activities, which increased degraded vegetation, agricultural fields, and bare soil areas. In contrast, from 2011 to 2021, dense vegetation began to recover and expand. It is important to note that despite this progress, the forest is still under threat from anthropogenic activities. Conserving this relict forest would further increase carbon storage and reduce the current global warming problem.