Controls on organic matter turnover under different land use in East Kalimantan

抄録

To analyze land use strategies to minimize soil degradation, effects of land use change on soil organic matter cycles were investigated in primary forest, Macaranga forest and Acacia mangium forest, alang-alang grassland, and palm oil plantation in Bukit Soeharto Experimental Forest in East Kalimantan, Indonesia. Soil C stock was smallest in palm oil plantation, while it was largest in grassland, Macaranga forest, and Acacia mangium forest. The cellulose tests (incubation of filter paper in surface soil) showed rapid decomposition in grassland and palm oil plantation. The decomposition of organic matter was faster in two secondary forests than in primary forest. The greater soil C stock in secondary forest and grassland is attributable to large input of fire-derived char. Soil C stock in palm oil plantation is decreasing due to rapid mineralization and erosion.