Boundary Effects on Benthic Microbial Phosphorus Concentrations and Diatom Beta Diversity in a Hydrologically-modified, Nutrient-limited Wetland

Authors

Evelyn E. Gaiser, Department of Biological Sciences and the Southeast Environmental Research Center, Florida International UniversityFollow
Pamela Sullivan, Department of Biological Sciences and the Southeast Environmental Research Center, Florida International UniversityFollow
Franco A.C. Tobias, Department of Biological Sciences and the Southeast Environmental Research Center, Florida International UniversityFollow
Andrew J. Bramburger, St. Lawrence River Institute of Environmental Sciences
Joel C. Trexler, Department of Biological Sciences and the Southeast Environmental Research Center, Florida International UniversityFollow

Abstract

Water flow and flooding duration in wetlands influence the structure and productivity of microbial communities partly through their influence on nutrient loading. The effect of flow-regulated nutrient loads is especially relevant for microbial communities in nutrient-poor settings, where delivery controls nutrient uptake rates and the intensity of microbial interactions. We examined the effect of hydrologic history and proximity to water sources on nutrient enrichment of benthic microbial assemblages (periphyton) and on their diatom species composition, along the artificial boundaries of Taylor Slough, a historically phosphorus-depleted drainage of the Florida Everglades. Concentrations of phosphorus in periphyton declined from the wetland boundary near inflow structures to 100-m interior, with spatial and temporal variability in rates dependent on proximity to and magnitude of water flow. Phosphorus availability influenced the beta diversity of diatom assemblages, with higher values near inflow structures where resources were greatest, while interior sites and reference transects contained assemblages with constant composition of taxa considered endemic to the Everglades. This research shows how hydrologic restoration may have unintended consequences when incoming water quality is not regulated, including a replacement of distinctive microbial assemblages by ubiquitous, cosmopolitan ones.

Comments

The final publication is available at Springer via http://dx.doi.org/10.1007/s13157-013-0379-z

This material is based upon work supported by the National Science Foundation through the Florida Coastal Everglades Long-Term Ecological Research program under Cooperative Agreements #DBI-0620409 and #DEB-9910514. Any opinions, findings, conclusions, or recommendations expressed in the material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

Recommended Citation

Gaiser, E.E., P. Sullivan, F. Tobias, A. Bramburger, J.C. Trexler. 2013. Boundary effects on benthic microbial phosphorus concentrations and diatom beta diversity in a hydrologically-modified, nutrient-limited wetland. Wetlands DOI: 10.1007/s13157-013-0379-z