Seasonal and spatial variation in fungal biomass in a forest soil

Abstract:
Abstract in Undetermined
Soil fungal biomass, determined by the fluorescein diacetate (FDA) method, was studied during a 3 yr period in three horizons in a mature and a clear-cut pine forest in Sweden with and without slash left on the ground. In the organic soil layer the amount of hyphae showed a similar seasonal periodicity at all three sites, and this periodicity was correlated to the soil moisture content. Such a periodicity was not found in the mineral soil. There were also annual differences in the amount of FDA-active hyphae which might be explained by different climatic conditions. The mean spatial variation in biomass content was 37.9% (coefficient of variation), which was almost as great as was the variation between different sampling dates. Only between 4 and 45% of the total variation in the fungal lengths could be explained by soil moisture and organic matter content.