Long-term experimental nitrogen deposition alters the composition of the active fungal community in the forest floor

Background/Question/Methods

Global increases in the rate of atmospheric nitrogen deposition have the potential to alter the composition and function of soil microbial communities.  Here, we tested the hypothesis that experimental N deposition has altered the composition of active communities of Dikarya fungi.  Such a change may underlie previously observed reductions in decomposition and increases in soil organic matter in a long-term field experiment. 

Results/Conclusions

The actively metabolizing forest floor fungal community was characterized from cDNA clone libraries constructed from 28S fungal rRNA extracted from the forest floor of two northern hardwoods stands in the lower peninsula of Michigan, USA.   We demonstrate that long-term experimental N deposition alters composition of the active community of Dikarya fungi in the forest floor.  Because forest floor fungi play an important role in the ecosystem process of decomposition, the alteration of the forest floor fungal community by increased N deposition may have ecosystem-level implications for the cycling and storage of C in forest ecosystems.