Changes in fruitbody production of mycorrhizal and litter decomposing macromycetes in heavy-metal polluted coniferous forests in north Sweden

Basidiomycete fruitbodies growing in coniferous forests along a complex heavy metal pollution gradient in north Sweden were identified and counted over a 4 yr period. The dominant metals in the humus layer were As, Cd, Cu, Pb, and Zn. Pb occurred at the highest levels in a range of 80 to 8500 g g–1 dry wt. Both the number of fruitbodies and the number of fruiting species decreased strongly with increasing pollution level. A few species appeared to sustain the metal loads. Many of these were ectomycorrhizal fungi. The relationship between fruitbody frequencies and plant species composition were also studied statistically although no obvious relations were found. Metal content of the fruitbodies of six species were also analyzed and their bioaccumulation calculated. Amanita muscaria accumulated Cd efficiently.