Indonesia's Forests So Damaged, Depleted That What's Left Now Burns W. Or W/O Drought
Air pollution caused by fires set for land-clearing on Sumatra has become a regularly occurrence in Southeast Asia, spurring hand-wringing in Singapore and Malaysia over health effects and worries among environmentalists over the climate impacts. While these fires are often termed "forest fires", the reality is much of the area that burns each year has already been deforested and today mostly consists of grass, scrub, and remnants of what was once forest. But the impacts are nonetheless very substantial, finds a new study published in the journal Scientific Reports.
The research, led by David Gaveau of the Center for International Forestry Research in Indonesia, assessed greenhouse gas emissions from fires that burned for a week in June 2013. While the fires were short-lived and almost entirely (82 percent) concentrated on already deforested lands representing less than 2 percent of Indonesia's land mass they released 172 million metric tons of carbon dioxide, or up to 10 percent of the country's annual greenhouse gas emissions. The reason for the large emissions was 84 percent of the burning occurred on peatlands, which store massive amounts of carbon in their soils.
Worryingly, the study notes that the fires occurred in a wetter-than-average year, suggesting that severe forest degradation in Sumatra due to years of clearing and peat drainage for industrial plantation development has set the stage for problem to worsen.
Our results demonstrate that the Indonesian fires of 2013 behind the record air pollution episode in Singapore were triggered by a seasonal two month dry spell in an otherwise rainy year. These fires were short-lived and confined to recently deforested peatlands in a localized area in Central Sumatra (in Riau Province), reflecting ongoing conversion to oil palm plantations" the authors write. "The area affected was much smaller than the 9.7–11.7 million ha that burned in 1997. However, the emissions of GHG and smoke during this brief localized event (one week and 1.6% of Indonesia’s land) were disproportionately large because of the peat.
EDIT
http://news.mongabay.com/2014/0821-deforested-forest-fires-riau.html