Estimation of carbon pools in secondary tropical deciduous forests of Odisha, India

Secondary tropical forests sequester atmospheric CO2 at relatively faster rates in vegetation and in soil than old-growth primary forests. Spatial understanding of biomass and carbon stocks in different plant functional types of these forests is important. Structure, diversity, composition, soil features and carbon stocks in six distinct plant functional types, namely: Moist Mixed-Deciduous Forest, Peninsular Sal Forest (PSF), Semi-Evergreen Forest (SEF), Planted Teak Forest, Bamboo Brakes (BB), and Degraded Thorny Shrubby Forest were quantified as secondary tropical deciduous forests of the Chandaka Wildlife Sanctuary, Eastern Ghats of Odisha, India. Seventy-one species ≥ 10 cm Girth at breast height (GBH) were recorded, belonging to 38 families and 65 genera. Above- ground biomass carbon and soil organic carbon ranged from 2.1–72.7 Mg C ha−1 and 20.6–67.1 Mg C ha−1, respectively, among all plant functional types. Soil organic carbon and important value index were positively correlated with above- ground biomass carbon. Maximum carbon allocation was in SOC pool (51–91%), followed by the above- ground biomass pool (9–52%), indicating SOC is one of the major carbon sinks in secondary dry forests. The results highlight the importance of secondary tropical deciduous forests in biodiversity conservation and ecological importance in reducing greenhouse gases.