Influences of Deforestation on Carbon Balance in a Natural Tropical Peat Swamp Forest in Thailand.

Abstract

The effects of deforestation on carbon balance in a natural tropical peat swamp forest were evaluated by micrometeorological monitoring. The monitoring sites were the primary forest at To-Daeng and the secondary forest at Bacho in Narathiwat Province, Thailand. The concentration gradient method (CG) and the relaxed eddy accumulation method (REA) were used to estimate the CO2 flux above the canopies. We estimated the annual amount of carbon absorption for both sites, using the relationship between CO2 flux and solar radiation for each site. An annual net carbon absorption of 5.32t C ha-1 year-1, was estimated for the primary forest. The accumulation of the released organic matter from the forest into logged-water caused the net carbon absorption in the peat swamp forest. In the secondary forest, annual net carbon absorption was estimated at 5.22 t C ha-1 year-1, which is almost the same range of absorption as the primary forest, because of plant growth in the secondary forest. A greater quantity of net carbon absorption, 9.69t C ha-1 year-1, was expected, assuming that the ground surface remained water-logged throughout the year. On the other hand, assuming it remained dry throughout the year, a net carbon emission of -0.40 t C ha-1 year-1, was expected.