Fungal Activity Associated with Decomposing Wood is Affected by Nitrogen Concentration in Water

Abstract

We examined the effect of two contrasting nitrogen concentrations in water (0.16 and 0.82 mg L-1) in the mass loss of pre-conditioned balsa wood, and associated fungal activity, in a laboratory microcosm experiment. Contrary to our predictions given the poor nutrient quality of balsa wood, an increase in dissolved nitrogen concentration did not result in increased mass loss or microbial oxygen consumption. Conidial production was stimulated in high, but not in low nitrogen microcosms, although the number of fungal species was similar between both treatments. The percentage contribution of each fungal species to total conidial production was similar at both N concentrations. The results support the notion that reproductive activity of aquatic hyphomycetes is the most sensitive microbial parameter to changes in the environment. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)