Management of Peat Fires on Smoldering Phase (Case Study: District Siak and District Kampar Riau Province)

Abstract

Oil palm plantation has been growing rapidly to fulfill resource stock for oil palm industry in Indonesia since 1967. Total area for oil palm plantations had increased from 5.6 million ha in 2005 to about 7.8 million ha in 2009. However for preparing the land for cultivation, improper land clearing by drainage peatland and prescribed burning induce main cause of uncontrolled peatland fires. Peatland fires usually occur at smoldering phase due to subsurface burning. During this smoldering phase, we measure near fire PM2.5 and its inorganic ions characteristics at Riau Province. Also based on observation in the field we proposed a buffer zone at burning site to prevent burning expansion. PM2.5 measurements were collected by Denuder at constant flow rate 10 L/min, while IC were used to quantify its inorganic ions. PM2.5 concentrations ratio relative to the background samples were quite high i.e at more than forty times reaching ambient concentration more than 2000 µg/m3. However the deviation of measured PM2.5 is quite high (531µg/m3) indicating high variability of occurring fires between sites. The inorganic ions composition were dominated by ions Cl−, SO42−, NH4+, K+. Slightly different composition with other land burning might be caused by pesticide residue within the oil palm plantation. Using observed peatland fire at the site, we design a proposed buffer zone to abate ambient PM2.5 which has an area of 4.4 ha. This buffer zone size might different with other burning condition at different sites.