Soil microbial response to Rhododendron understory removal in southern Appalachian forests: Effects on extracellular enzymesAuthor(s): Ernest D. Osburn; Katherine J. Elliottt; Jennifer D. Knoepp; Chelcy F. Miniat; J.E. Barrett
Source: Soil Biology and Biochemistry
Publication Series: Scientific Journal (JRNL)
Station: Southern Research Station
Download Publication (1.0 MB)
Rhododendron maximum is a native evergreen shrub that has expanded in Appalachian forests following declines of american chestnut (Castanea dentata) and eastern hemlock (Tsuga canadensis). R. maximum is of concern to forest managers because it suppresses hardwood tree establishment by limiting light and soil nutrient availability. We are testing R. maximum removal as a management strategy to promote recovery of Appalachian forests. We hypothesized that R. maximum removal would increase soil nitrogen (N) availability, resulting in increased microbial C-demand (i.e. increased C-acquiring enzyme activity) and a shift towards bacterial-dominated microbial communities. R. maximum removal treatments were applied in a 2 × 2 factorial design, with two R. maximum canopy removal levels (removed vs not) combined with two O-horizon removal levels (burned vs unburned). Following removals, we sampled soils and found that dissolved organic carbon (DOC), N (TDN, NO3, NH4), and microbial biomass all increased with R. maximum canopy + O-horizon removal. Additionally, we observed increases in C-acquisition enzymes involved in degrading cellulose (β-glucosidase) and hemicellulose (β-xylosidase) with canopy + O-horizon removal. We did not see treatment effects on bacterial dominance, though F:B ratios from all treatments increased from spring to summer. Our results show that R. maximum removal stimulates microbial activity by increasing soil C and N availablility, which may influence recovery of forests in the Appalachian region.
- You may send email to email@example.com to request a hard copy of this publication.
- (Please specify exactly which publication you are requesting and your mailing address.)
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
CitationOsburn, Ernest D.; Elliottt, Katherine J.; Knoepp, Jennifer D.; Miniat, Chelcy F.; Barrett, J.E. 2018. Soil microbial response to Rhododendron understory removal in southern Appalachian forests: Effects on extracellular enzymes. Soil Biology and Biochemistry. 127: 50-59. https://doi.org/10.1016/j.soilbio.2018.09.008.
KeywordsRhododendron maximum, carbon, nitrogen, extracellular enzymes, bacteria, fungi
- Solid residues from Ruminococcus cellulose fermentations as components of wood adhesive formulations
- Changes in bacterial gut community of Reticulitermes flavipes (Kollar) and Reticulitermes tibialis Banks after feeding on termiticidal bait material
- Leaf litter decomposition and microbial activity in nutrient-enriched and unaltered reaches of a headwater stream
XML: View XML