Hyporheic Zone Microbiome Assembly Is Linked to Dynamic Water Mixing Patterns in Snowmelt‐Dominated Headwater Catchments
AuthorSaup, C. M.
Bryant, S. R.
Nelson, A. R.
Harris, K. D.
Sawyer, A. H.
Christensen, J. N.
Tfaily, M. M.
Williams, K. H.
Wilkins, M. J.
AffiliationUniv Arizona, Dept Soil Water & Environm Sci
MetadataShow full item record
PublisherAMER GEOPHYSICAL UNION
CitationSaup, C. M., Bryant, S. R., Nelson, A. R., Harris, K. D., Sawyer, A. H., Christensen, J. N., et al. (2019). Hyporheic zone microbiome assembly is linked to dynamic water mixing patterns in snowmelt‐dominated headwater catchments.Journal of Geophysical Research: Biogeosciences, 124. https://doi.org/10.1029/2019JG005189
RightsCopyright © 2019. American Geophysical Union.All Rights Reserved.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at firstname.lastname@example.org.
AbstractTerrestrial and aquatic elemental cycles are tightly linked in upland fluvial networks. Biotic and abiotic mineral weathering, microbially mediated degradation of organic matter, and anthropogenic influences all result in the movement of solutes (e.g., carbon, metals, and nutrients) through these catchments, with implications for downstream water quality. Within the river channel, the region of hyporheic mixing represents a hot spot of microbial activity, exerting significant control over solute cycling. To investigate how snowmelt‐driven seasonal changes in river discharge affect microbial community assembly and carbon biogeochemistry, depth‐resolved pore water samples were recovered from multiple locations around a representative meander on the East River near Crested Butte, CO, USA. Vertical temperature sensor arrays were also installed in the streambed to enable seepage flux estimates. Snowmelt‐driven high river discharge led to an expanding zone of vertical hyporheic mixing and introduced dissolved oxygen into the streambed that stimulated aerobic microbial respiration. These physicochemical processes contributed to microbial communities undergoing homogenizing selection, in contrast to other ecosystems where lower permeability may limit the extent of mixing. Conversely, lower river discharge conditions led to a greater influence of upwelling groundwater within the streambed and a decrease in microbial respiration rates. Associated with these processes, microbial communities throughout the streambed exhibited increasing dissimilarity between each other, suggesting that the earlier onset of snowmelt and longer periods of base flow may lead to changes in the composition (and associated function) of streambed microbiomes, with consequent implications for the processing and export of solutes from upland catchments.
Note6 month embargo; published online: 26 October 2019
VersionFinal published version
SponsorsGeological Society of America; Central Ohio Gem and Mineral Society; OSU's School of Earth Sciences' Friends of Orton Hall; Biological and Environmental Research program in the U.S. DOE Office of Science [DE-SC0016488]; Watershed Function Scientific Focus Area at Lawrence Berkeley National Laboratory; U.S. Department of Energy (DOE) Subsurface Biogeochemical Research Program, DOE Office of Science, Office of Biological and Environmental ResearchUnited States Department of Energy (DOE) [DE-AC0205CH11231]; Office of Biological and Environmental Research (BER)