Biomass and Carbon Stock Estimation in Different Mangrove Areas in Mangunharjo Village, Semarang, Indonesia

Mangroves are one of the coastal ecosystems that play a crucial role in carbon storage. This study aims to determine the differences in biomass and carbon stock values across different mangrove areas, namely natural, mangroves near aquaculture ponds, and rehabilitated mangrove in Mangunharjo Subdistrict, Semarang. The method used in this study was a field survey intended to measure the diameter of mangrove tree trunks as the baseline data for calculating mangrove stand carbon stock. The research was conducted in three areas selected using purposive sampling: natural mangroves, mangroves near aquaculture ponds, and rehabilitated mangroves, with each area consisting of two sampling stations and three transect plots, each. The size of the transect plots used was 10 m × 10 m. Data collection employed a non-destructive method based on allometric equations to estimate mangrove stand biomass. Overall, the estimated carbon stock of mangrove stands in Mangunharjo Subdistrict was 7,257.708 tons of carbon (tonC), with an average carbon stock value across the three areas of 120.36 tons/ha. The results showed that the rehabilitated mangrove area had the highest average biomass and carbon stock values, with biomass of 290.47 ± 23.19 tons/ha and carbon stock of 127.60 ± 10.23 tons/ha, followed by the near aquaculture ponds mangrove area with biomass and carbon stock values of 268.39 ± 66.16 tons/ha and 117.63 ± 28.96 tons/ha, respectively. The lowest values were found in the natural mangrove area, with biomass and carbon stock values of 264.25 ± 57.23 tons/ha and 115.85 ± 25.30 tons/ha, respectively.