POTENSI JENIS DAN CADANGAN KARBON HUTAN DATARAN RENDAH DI IUPHHK PT. SALAKI SUMMA SEJAHTERA, KEPULAUAN MENTAWAI

Tropical forest is a terrestrial ecosystem with a very high species diversity and composed of stands with varying degrees of ages. The ability to absorb carbon is getting limited because one of the causes is rapid deforestation. The important role of forest as a carbon and biomass storage and sink could change to be a source of CO2 emitter to the atmosphere. Biomass and carbon assessment especially in the ecosystem of archipelago is still rare. This study aimed to determine the diversity of vegetation and establish allometric equations to estimate the potential content of biomass, carbon and CO2 sequestration in PT. Salaki Summa Sejahtera. The study was conducted in PT SSS working areas in the Mentawai Islands District. Tree sample was selected with purposive and data collected with destructive sampling, 30 trees were sampled. Analysis of carbon content test was employed with Walkley and Black method by spectrophotometry. Biomass and carbon content and CO2 sequestration was estimated with allometric equation approach. The study derived the composition of vegetation that composed the monitoring plot of Permanent Sample Plot of PT Salaki Summa Sejahtera which dominated with Dipterocarpus elongatus Korth from the famili of Dipterocarpaceae. The highest content of biomass was in the stem organ of 14722.05 kg (61%), subsequent branch/ twig organ of 5495.99 kg (22%), root organ of 2695.98 kg (11%) and the lowest, leaf organ of 1251.13 kg (5%). The highest carbon content was in stem organ of 7893.98 kg (63%), subsequent branch/ twig of 2816.41 (22%), root organ of 1320.61 kg (11%) and the lowest, leaf organ of 532.47 kg (4%). Allometric equation established to estimate the total biomass potential is (Wt) = 0.863714 (dbh)1.734982 (R2 = 0.966,) while for estimating the total carbon content used allometric equation of (Ct) = 0.142801 (dbh) 2.007412 (R2 = 0.971). The potential of CO2 sequestration was 1336.05 tons and per hectare potential was 222.68 tons CO2/ha