Estimation of carbon stock, biomass and CO₂ sequestration at mangrove forest in Batu Rusa River and Serata Pasir Padi, Bangka Island

Abstract The aim of this research is to determine the total biomass, carbon stock and CO 2 sequestration above ground in mangrove forests in the Baturusa and Pasir Padi River Basins. This research was carried out in October-September 2023-2024, using a non-destructive sampling method based on species-specific allometric equations to find the biomass value of mangrove stands. Data collections were determined using the random purposive sampling method. The result shows that Rhizophora apiculata is the mangrove species that dominates in the Baturusa River, while the Excoecaria agallocha dominates in the Pasir Padi River mangrove forest. The total biomass reserves above ground in the Baturusa River and Pasir Padi River mangrove forests are quite high, namely 195310.4 tonnes/ha, with 188172.2 tonnes/ha for the biomass of the Baturusa River mangrove stands while the mangrove stands in Pasir Padi are 7138.2 tonnes. /Ha. The total above-ground (standing) carbon stock in the Baturusa River mangrove forest is 88440.9 tonnes/ha while in the Pasir Padi River it is 3354.9 tonnes/ha with a total reaching 91795.9 tonnes/ha. The total uptake of CO 2 sequestration in mangrove stands in the Baturusa River was 324283.4 tonnes/ha, the Pasir Padi River was 122301.5 tonnes/ha with a total reaching 336585.0 tonnes/ha. Sonneratia alba is a mangrove species that has the highest biomass reserves, carbon stock and CO 2 sequestration, namely biomass of 0.701 tonnes/tree, carbon stock of 0.330 tonnes/tree and CO 2 uptake of 1.208 tonnes/tree, because it has a fairly large trunk diameter compared to other mangrove species.