Valuasi Ekonomi Karbon Biru pada Ekosistem Mangrove di Kecamatan Maginti, Kabupaten Muna Barat

Abstract

Mangrove ecosystems store carbon in vegetation and sediments, providing a basis for assessing the economic value of blue carbon. This study aimed to quantify mangrove carbon stocks and estimate their economic value in Maginti District, West Muna Regency, Indonesia. Vegetation was assessed using thirty 10 × 10 m quadrat plots distributed across three mangrove zones. Aboveground and belowground biomass were estimated using allometric equations and converted to carbon stocks using a carbon fraction of 0.47. Sediment organic carbon stocks were estimated from bulk density and organic matter content determined using loss on ignition at four depth intervals spanning 0–100 cm. Economic valuation converted carbon stocks to CO₂ equivalents using a factor of 44/12 and applied price scenarios of USD 5–10 per tonne of CO₂ equivalent, with an assumed exchange rate of IDR 17,000 per USD. The estimated total ecosystem carbon stock was 499.59 Mg C ha⁻¹, equivalent to 1,831.83 Mg CO₂e ha⁻¹. Sediment organic carbon contributed 63.48% of the total, followed by aboveground carbon at 26.03% and belowground carbon at 10.49%. The indicative economic value ranged from IDR 155.71 million to IDR 311.41 million ha⁻¹. Extrapolation to a mangrove area of 953.16 ha yielded a landscape value of IDR 148.41–296.82 billion, assuming that the sampled mean carbon stock represented the entire area. These estimates represent scenario-based valuations of existing carbon stocks rather than verified tradable carbon credits or realizable carbon-market revenue. The findings highlight the contribution of sediment carbon and provide preliminary information to support mangrove conservation planning and further assessment of carbon financing opportunities.