Abstract:
Peatlands in the Biosphere Reserve Giam Siak Kecil- Bukit Batu (GSK-BB), Riau are
mostly converted into Timber Plantation (TP) Acacia sp., oil palm plantation, rubber
plantation and settlements. Peatland conversion will affect the population and soil
microbial activity. Population and soil microbial activity are indicators that are
sensitive to soil quality. This research aimed to monitor the impact of peatland
conversion into a TP Acacia sp., oil palm plantation, rubber plantation, restoration
land and burn land through soil physicochemical was determined using standard
method and total microbial population of bacterial and fungi was quantified using
Total Plate Count (TPC) method. Soil samples were taken in six different locations,
namely secondary forest, TP Acacia sp., oil palm plantation, rubber plantation,
restored land, burned land. Soil physicochemical character varies with pH,
temperature, weight of volume, dry weight, and water content ranged from 3,23-
4,23, 27,0 – 30,25 oC, 0,20- 0,29 gr/cm3, 0,20- 0,31 g dan 221,97- 401,98 %. Total
population of Bacteria ranged from 7,60-13,20 x105 CFU/g soils. Total population of
Fungi ranged from 2,80- 5,90 x104 CFU/g soils. Bacteria and fungi populations on
converted land tended to be higher than in secondary forest. The result showed that
land conversion affected the total population of bacteria and fungi. On other hand, the
effect of peatland conversion on soil physicochemical character did not show a clear
trend. Therefore, bacteria and fungi populations can be used as indicators of peatland
quality.