PHYSICAL AND CHEMICAL PROPERTIES OF SOILS IN THE FIRE-AFFECTED FOREST OF EAST KALIMANTAN, INDONESIA

Abstract

The ecological recovery of Dipterocarpaceae forest in East Kalimantan, Indonesia, after the forest fire in 1997–1998 was studied. Soil physical and chemical properties of the plots—heavily damaged by forest fire (HD), lightly damaged by fire (LD) and control site not burned by fire (K)—were investigated eight to nine years after the fire. Soil water content was monitored for one year in the HD and K plots. The white sand layer found in the HD plot had low water retention and high permeability. Therefore, soil was not saturated in the surface sandy layer during rainfall and water infiltrated quickly into the subsurface layer. Such sandy soil, often found in kerangas forest, generally has low pH and low nutrient availability. However, the sandy soil in the HD plot had higher pH and lower electrical conductivity (EC) than other pits at the upper boundary of the sandy soil. Total carbon, total nitrogen and water repellency were high at the lower boundary of the sandy layer. This may be because ash and charcoal produced by the fire have leached downwards.