Biomass and Carbon Storage of Four Forest Tree Species at Prachuap Khiri Khan Silvicultural Research Station, Prachuap Khiri Khan Province.

Abstract

This study is aimed to create biomass equation, and compare the biomass and carbon storages of four forest tree Species, namely Pterocarpus macrocapus Kurz, Hopea odorata Roxb, Azadirachta indica A. Juss and Azadirachta excelsa (Jack) Jacobs, at 21-year old at Prachuap Khiri Khan Silvicultural Research Station, Prachuap Khiri Khan Province,Thailand. For each tree species, a 20 m x 20 m sample plot were out and dimensions of all trees were measured accordingly. In order to estimate tree biomass by using allometric equations, tree samples were cut according to a stratified-clip technique and different parts of sample trees were taken for carbon content analysis to assess the carbon storage in biomass.

The result indicated that the highest growth and biomass was observed in A. indica  followed by H. odorata , P. macrocapus , and A. excelsa. with the total biomass of 154.76, 131.81, 126.41 and 104.96 tonne/ha respectively. There was statistically significant difference among tree species (P<0.05). In contrast, the average carbon contents in aboveground biomass (stem, branch and leaf) were higher in tissues of H. odorata than in those of P. macrocapus, A. indica and A. excelsa with the mean values of 48.79, 46.07, 45.55 and 45.12 % of dry weight respectively. There was statistically significant difference among tree species (P<0.01). The carbon storages in tree biomass the same trend of biomass;  A. indica had greatest carbon storage in the total biomass (69.28 tonne/ha) followed by H. odorata (64.94 tonne/ha) P. macrocapus (57.78 tonne/ha) and A. excelsa (46.73 tonne/ha), respectively. The findings also suggested that variation in tree biomass production than carbon contents, was rather accounted for the difference in carbon storage in these tree species.