Spatiotemporal Heterogeneity of Water Flowpaths Controls Dissolved Organic Carbon Sourcing in a Snow-Dominated, Headwater Catchment

Simple item page
dc.contributor.authorRadke, Anna G.en
dc.contributor.authorGodsey, Sarah E.en
dc.contributor.authorLohse, Kathleen A.en
dc.contributor.authorMcCorkle, Emma P.en
dc.contributor.authorPerdrial, Juliaen
dc.contributor.authorSeyfried, Mark S.en
dc.contributor.authorHolbrook, W. Stevenen
dc.contributor.departmentGeosciencesen
dc.date.accessioned2019-10-28T13:14:34Zen
dc.date.available2019-10-28T13:14:34Zen
dc.date.issued2019-02-27en
dc.description.abstractThe non-uniform distribution of water in snowdrift-driven systems can lead to spatial heterogeneity in vegetative communities and soil development, as snowdrifts may locally increase weathering. The focus of this study is to understand the coupled hydrological and biogeochemical dynamics in a heterogeneous, snowdrift-dominated headwater catchment (Reynolds Mountain East, Reynolds Creek Critical Zone Observatory, Idaho, USA). We determine the sources and fluxes of stream water and dissolved organic carbon (DOC) at this site, deducing likely flowpaths from hydrometric and hydrochemical signals of soil water, saprolite water, and groundwater measured through the snowmelt period and summer recession. We then interpret flowpaths using end-member mixing analysis in light of inferred subsurface structure derived from electrical resistivity and seismic velocity transects. Streamwater is sourced primarily from groundwater (averaging 25% of annual streamflow), snowmelt (50%), and water traveling along the saprolite/bedrock boundary (25%). The latter is comprised of the prior year's soil water, which accumulates DOC in the soil matrix through the summer before flushing to the saprolite during snowmelt. DOC indices suggest that it is sourced from terrestrial carbon, and derives originally from soil organic carbon (SOC) before flushing to the saprolite/bedrock boundary. Multiple subsurface regions in the catchment appear to contribute differentially to streamflow as the season progresses; sources shift from the saprolite/bedrock interface to deeper bedrock aquifers from the snowmelt period into summer. Unlike most studied catchments, lateral flow of soil water during the study year is not a primary source of streamflow. Instead, saprolite and groundwater act as integrators of soil water that flows vertically in this system. Our results do not support the flushing hypothesis as observed in similar systems and instead indicate that temporal variation in connectivity may cause the unexpected dilution behavior displayed by DOC in this catchment.en
dc.description.notesThis study was conducted in collaboration and cooperation with the USDA Agriculture Research Service, Northwest Watershed Research Center, Boise, Idaho, and landowners within the Reynolds Creek Critical Zone Observatory (RC CZO). Support for this research was provided by NSF for RC CZO Cooperative agreement NSF EAR-1331872. Additional support was provided by the Idaho State University Department of Geosciences Geslin Award.en
dc.description.sponsorshipNSFNational Science Foundation (NSF) [NSF EAR-1331872]; Idaho State University Department of Geosciences Geslin Awarden
dc.format.mimetypeapplication/pdfen
dc.identifier.doihttps://doi.org/10.3389/fevo.2019.00046en
dc.identifier.issn2296-701Xen
dc.identifier.other46en
dc.identifier.urihttp://hdl.handle.net/10919/95182en
dc.identifier.volume7en
dc.language.isoenen
dc.publisherFrontiersen
dc.rightsCreative Commons Attribution 4.0 Internationalen
dc.rights.urihttp://creativecommons.org/licenses/by/4.0/en
dc.subjectdissolved organic carbon/DOCen
dc.subjecthydrologic connectivityen
dc.subjectsoil wateren
dc.subjectgroundwateren
dc.subjectsnowen
dc.subjectdryland ecosystemsen
dc.subjectcritical zone observatory/CZOen
dc.titleSpatiotemporal Heterogeneity of Water Flowpaths Controls Dissolved Organic Carbon Sourcing in a Snow-Dominated, Headwater Catchmenten
dc.title.serialFrontiers in Ecology and Evolutionen
dc.typeArticle - Refereeden
dc.type.dcmitypeTexten
dc.type.dcmitypeStillImageen

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
fevo-07-00046.pdf
Size:
8.12 MB
Format:
Adobe Portable Document Format
Description:
Download

Collections

Scholarly Works, Geosciences