Dry deposition of elemental carbon on leaves of a tropical forest in Sakaerat, Thailand

Dry deposition of elemental carbon (EC) was investigated in a tropical dry deciduous forest, Sakaerat, Thailand. To estimate EC dry deposition, micro-meteorological measurements and monthly sampling of PM25 aerosols were carried out continuously over one year in 2010 at the top of an experimental tower in the forest. EC strongly adsorbed on leaf surface was extracted by chloroform and filtrated on a silica filter. For wet deposition, sampling of EC directly filtrated from rainwater was carried out inside and outside of the forest. Dry deposition increased during the period from February to April when the concentration and deposition velocity were both high. Wet deposition peaked in March because of the washout effect of high EC in the atmosphere of the late dry season. The annual dry deposition was more than 10 times higher than the wet deposition. Estimated dry deposition onto the leaves was less than total dry deposition. Other part possibly deposited bark surface and ground surface especially in the leafless season.