© 2000 Heron Publishing—Victoria, Canada
Effects of continuous optimal fertilization on belowground ectomycorrhizal community structure in a Norway spruce forest
Petra M. A. Fransson (1), Andy F. S. Taylor (1) and Roger D. Finlay (1)
1. Department of Forest Mycology and Pathology, SLU, Box 7026, S-75007 Uppsala, Sweden / Received June 21, 1999
Summary
Studies of effects of fertilizer treatment on ectomycorrhizal fungal community structure have predominantly been based on
large, single additions of nitrogen. Studies involving chronic additions of nutrients in combination with irrigation are much
less common. We used morphotyping to study effects of balanced additions of a nutrient solution on ectomycorrhizal fungal
community structure in a 36-year-old stand of Picea abies (L.) Karst. Despite high variability among individual samples, principal components analysis revealed a clear shift in community
structure in response to fertilization. Irrigated plots receiving only water did not differ significantly from untreated control
plots. Mycorrhizal root tips colonized by Cenococcum geophilum Fr. were significantly more common in fertilized plots than in control plots. Possible responses by other ectomycorrhizal
species were masked by high variability. Over sixty morphotypes were distinguished, but there was no measurable effect of
either fertilizer or irrigation treatment on morphotype richness or total number of root tips.
Keywords:
biodiversity, fungi, mycorrhiza, Picea abies
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