This study aims to assess the carbon storage capability of dominant vegetative land covers in Thailand by estimating biomass, biomass carbon and soil carbon stocks. Above-ground biomass was estimated from allometric equation or actual raw yield. Soil organic carbon was analyzed according to the Chromic acid titration method. Results show that above-ground biomass carbon for irrigated rice, sugarcane, mature Para rubber, degraded rain forest and mixed deciduous forest were 0.8- 1.3, 11.1, 91.5, 56.6 and 60.5 tonne C ha-1, respectively; whereas topsoil carbon at 0-30 cm were 14.9-21.3, 11.3-13.8, 34.2, 54.6 and 77.7-136.9 tonne C ha-1, respectively. Additional studies on the roles of leaf litters involving soil carbon and effects of agricultural practices on carbon storage capability should be considered. Furthermore, advantages of bio-fuel over the lost organic carbon in agricultural systems and decline in crop yield could be also taken into account.
