Impacts of biomass burning and regional haze on the pH of rainwater in Brunei Darussalam

A number of reports have suggested that biomass burning in the tropics may have an acidifying effect on precipitation with consequent effects on tropi cal ecosystems. Although SE Asia has been repeatedly affected by severe haz e caused by tropical forest fires, the impacts on rainwater acidity and che mistry have not yet been reported. In the present communiction we report, f or the first time, the impacts of fires and haze on rainwater pH in SE Asia during the past three haze episodes. The analysis of rainwater in Brunei D arussalam during severe haze episodes in Borneo in 1994, 1997, and 1998 fai led to reveal any significant impacts on rainwater acidity or wet depositio n of hydrogen ions. (C) 2000 Elsevier Science Ltd. All rights reserved.