Carbon stock in calophyllum inophyllum provenances from eight islands in Indonesia: associate soil physicochemical properties and litter fiber content

Calophyllum inophyllum is a superior choice for sustainable biodiesel production. this tree ishighly productive, adaptable to various land types, and has a significant potential for carbonsequestration. this study aimed to determine carbon storage variation in biomass, litter, andsoil among C. inophyllum provenances from eight islands in indonesia; identify the bestallometric model for estimating total plant biomass carbon stock; and assess the impact ofsoil physicochemical properties and litter fiber content on total carbon stock. Plant, litter andsoil samples were purposively selected from a total of 32 sample points of 8 provenances.analysis of variance was carried out to determine variations among provenances on carbonstorage in plant biomass and its components (stems, branches, twigs, leaves, stumps, androots), in litter, as well as in soil organic carbon. the best allometric equation was selected toestimate the total plant biomass carbon based on the value of coefficient determination (R2)and RMse (Root Mean square error). Redundancy analysis (RDa) was carried out to determinethe effect of the soil physicochemical properties and litter fiber content on total biomasscarbon and total soil organic carbon followed by a partial analysis (Variation Partitioninganalysis). the results of this study showed that variations on carbon storage in plant biomassand its components, in litter, as well as in soil organic carbon were not significantly differentamong the provenances. the tBc averaged 13.46 tons ha−1, the litter carbon 4.75 tons ha−1,and tsOc 75.91 ton ha−1 with most biomass carbon stored in trunks (31.02%) and most ofcarbon stock was stored as tsOc (81%). Quadratic (tBc = 0,4172DBh2 - 1,3433DBh + 2,3498)was the best allometric model for estimating carbon storage on plant biomass with diameterat breast height (DBh) as a predictor variable. Most of the variation in total carbon stock wasinfluenced by soil chemical properties (76%) followed by soil physical properties (11%) andlitter fiber content (5%). this study implies that the development of C. inophyllum in indonesiafor carbon storage may utilize seeds or planting materials from any origin, disregardingprovenances. applying organic and/or mineral nutrients (N, P, and K) will increase carbonstock in C. inophyllum plantations. this study underscores the significance of assessing C.inophyllum carbon stocks to enhance its role in establishing climate change policies andpromoting sustainable resource management.