Litter breakdown and fungal diversity in a stream affected by mine drainage
Niyogi, Dev K.; Cheatham, Cory A.; Thomson, William H.; Christiansen, Jessica M.
published: Jun 1, 2009
ArtNo. ESP141017501003, Price: 29.00 €
We examined litter breakdown and fungal communities at three sites along a small mountain stream affected by mine drainage in Colorado. One site was located in the drainage from an abandoned mine, and the 2 other sites were upstream and downstream of the confluence of the drainage with a pristine stream. At the 2 sites affected by the mine drainage, pH was depressed, zinc concentration was elevated, and metal hydroxides were deposited onto the stream bottom and leaf litter. At these sites, litter breakdown was slower, shredding invertebrates were absent, and microbial activity was also lower compared to the upstream site. Conidia production by aquatic hyphomycetes was limited at all sites, but indicated differences in species diversity and identity. The mining sites were both dominated by Varicosporium elodea, while the upstream site had several taxa that produced conidia. Molecular analysis by denaturing gradient gel electrophoresis of PCR-amplified ITS regions showed similar patterns, but revealed more taxa at the upper and lower sites than seen with conidia examination. In these stressed streams, litter breakdown was slower and associated biota, including shredders and fungi, reflected changes from the suite of stressors associated with acid mine drainage.