Microbial population of spruce soil in Tatachia mountain of Taiwan

To investigate the role of microorganisms in the ecology and the nutrient transformation of forest soil, soil property, microbial population, biomass and organic acid content of Spruce soil in Tatachia mountain were determined during January 1997 to November 1999. Soil temperatures were between 5.5 and 15.6 °C and soil pH ranged from 3.6 to 5.0. Total organic carbon and nitrogen contents ranged from 5.83% to 34.35% and from 0.90% to 3.19%, respectively. C/N ratio was between 7.07 and 18.24. Each gram of dry soil contained microbial biomass carbon 308–870 μg, microbial biomass nitrogen 107–240 μg, malic acid 74–211 nM and succinic acid 32–175 nM. In addition, each gram of dry organic layer contained microbial biomass carbon 216–653 μg, microbial biomass nitrogen 10.3–33.8 μg, formic acid 256–421 nM, acetic acid 301–435 nM, malic acid 795–1027 nM and succinic acid 204–670 nM. About 45.5–90.9% of topsoil samples had higher microbial population than those of subsoil especially in actinomycetes, cellulolytic and phosphate-solubilizing microorganisms. Although rhizosphere of Spruce had higher total organic carbon and total nitrogen content than non-rhizosphere and dwarf bamboo areas, the microbial population had no significant difference among them.