Abstract
In order to apply an easily and speedily method measuring microbial activities using FDA hydrolysis to forest soils, we improved the measuring condition using different from microbial activities soil on same geology. Fluorescence of FDA was measured by absorbance at 490nm(A_<490>). 0.25g(dry weight) of soil was added to 20ml of 60mM sodium phosphate buffer (862.5mL of 0.06M Na_2HPO_4+137.5mL of 0.06M NaH_2PO_4), pH7.6, then about 1ml of FDA solution (2mg/mL) was added. Immediately, the mixture solution was shaken at 25℃ for 30 minutes, and added with acetone to terminate the hydrolysis of FDA. Mixture solution filtered through no.3 filter paper was used to determine absorbance at 490nm. The resultant A_<490> reflected microbial biomass C, soil respiration rates, fungal counts and organic matter decomposition rates in soils. These results showed that A_<490> represented microbial activities as decomposer in forest ecosystem.