Effects of Seasonal Changes on Microbial Biomass and Respiration of Forest Floor and Topsoil under Bornmullerian Fir Stand

Abstract

A significant parameter that links plants to soil is microbial biomass. Therefore, measurement of the biologically-active fractions of the soil organic matter, such as microbial biomass C, N and P, is a good way to quantify the quality of the soil. In this study, the seasonal dynamics of microbial biomass C, N and P and associated microbial properties were investigated in the forest’s floor (litter, fermentation and humus) and topsoil (0 – 5 cm) under a stand of Bornmullerian fir ( Abies nordmanniana subsp . bornmülleriana Mattf.). According to One-Way ANOVA, the study showed that seasonal changes have a significant effect on the quantities of microbial biomass C, N and P and associated microbial properties in the forest’s floor and soil. For example, the greatest amounts of microbial biomass C, N and P in the forest’s floor and topsoil occurred during summer. Also, seasonal variations have significant effects on microbial biomass C, N and P in the forest’s floor and soil because they alter the climate and chemical characteristics of the soil. A nnual releases of C, N and P through microbial biomass were higher in the forest’s floor than in soil. The results of this study indicated that variations in the microbial biomass and basal respiration during the different seasons are related to changes microbial activity.     Keywords: Basal respiration, biochemical properties, C mic :C org percentage, C mic :P mic ratio, metabolic quotient (qCO 2 )