Seasonal fluctuations of active fungal biomass in horizons of a podzolized pine-forest soil in central Sweden

In English Metabolically-active fungal biomass determined by fluorescein diacetate (FDA) staining, was studied during a 27-month period in three horizons of a podzolized pine-forest soil. Recurrent biomass peaks were registered in autumn and early spring. Biomass increase was also noted during the winter with soil temperatures below 0 deg C. Only a minor fraction (2.4-4.3%) of the total fungal biomass was active. The FDA-active biomass was equally distributed between the organic (5 cm) and mineral (15 cm) soil horizons, and varied between 0.5 and 2.4 g d.w. m-2. The amount of FDA-active biomass was correlated with soil moisture content.