ENUMERASI TOTAL POPULASI MIKROBA TANAH GAMBUT DI TELUK MERANTI KABUPATEN RIAU

Abstract

Teluk Meranti is one of the peatland area in Riau province. Most of these lands have been
changed into palm oil plantation, timber plantation, agricultural area and settlement. The
aim of this research was to analyze the impact of land use changes on soil physical-
chemical characteristics and microbial cell number. Soil samples were taken from eight
different locations, namely primary forest as control, secondary forest, rubber plantation
(15 monthsyears old), rubber forest (40-60 years old), palm oil plantation (7-8 years old),
acacia plantation (2-3 years old), corn field, and cassava field. Microbial cell number was
determined by spread plate method, employing appropriate media for the growth of
bacteria, fungi and actinomycetes. The results showed that the soil humidity, soil
temperature, percentage of soil dry weight, water content, soil bulk density and pH ranged
from 29,63-55,88%, 27-31,5 o C, 14,9-35,5%, 64,9-85,1%, 0,16-0,39 g/cm 3 and 3,63-4,00,
respectively. The copiotrophic bacterial cell number ranged from 0,6x10 5 -1,8x10 5 CFU/g
soil where the highest population was at the palm oil plantation,whereas the oligotrophic
bacterial cell number ranged from 0,5x10 5 -1,4x10 5 CFU/g soil where the highest population
was at the palm oil plantation. The population of fungi ranged from 0,4x10 5 -1,0x10 5 CFU/g
soil where the highest population was at the corn field. The population of actinomycetes
ranged from 0,4x10 5 -10,7x10 5 CFU/g soil where the highest population was at the palm oil
plantation. Land use changes caused microbial cell number increased. The results indicated
that land use changes influenced the microbial cell numbers.