New allometric equations for quantifying tree biomass and carbon sequestration in seasonally dry secondary forest in northern Thailand

As tropical deforestation and forest degradation accelerate, carbon-credit trading could provide a financial incentive to preserve and regenerate forests. Since carbon trading relies on the accurate quantification of carbon stocks, allometric equations are urgently needed to derive above-ground dry biomass (AGB) from easily measured variables. Few allometric equations have been published for regenerating secondary forests in Southeast Asia. This study established new allometric equations, to determine AGB and carbon in regenerating secondary forests on shifting cultivation fallows in northern Thailand. To develop the equations, data were collected from 78 trees (136 felled individual stems, including coppices) ranging in size from 1 to 32.9 cm diameter at breast height (D). The dependent variable was AGB. The independent variables were D, tree height (H) and wood density (WD). Wood density varied significantly among species ( p