Impact of Dynamically Changing Discharge on Hyporheic Exchange Processes Under Gaining and Losing Groundwater Conditions

Liwen Wu, Tanu Singh, Jesus Gomez-Velez, Gunnar Nützmann, Anders Wörman, Stefan Krause, Jörg Lewandowski

Research output: Contribution to journalArticlepeer-review

36 Scopus citations

Abstract

Channel discharge, geomorphological setting, and regional groundwater flow determine the spatiotemporal variability of bedform-induced hyporheic exchange and the emergence of biogeochemical hot spots and hot moments that it drives. Of particular interest, and significantly understudied, is the role that dynamically changing discharge has on the hyporheic exchange process and how regional groundwater flow modulates the effects of transience. In this study, we use a reduced-complexity model to systematically explore the bedform-induced hyporheic responses to dynamically changing discharge events in systems with different bedform geometries exposed to varying degrees of groundwater flow (under both upwelling and downwelling conditions). With this in mind, we define metrics to quantify the effects of transience: spatial extent of the hyporheic zone, net hyporheic flux, mean residence time, and denitrification efficiency. We find that regional groundwater flow and geomorphological settings greatly modulate the temporal evolution of bedform-induced hyporheic responses driven by a single-peak discharge event. Effects of transience diminish with increasing groundwater upwelling or downwelling fluxes, decreasing bedform aspect ratios, and decreasing channel slopes. Additionally, we notice that increasing discharge intensities can reduce the modulating impacts of regional groundwater flow on the effects of transience but hardly overcomes the geomorphological controls. These findings highlight the necessities of evaluating hyporheic exchange processes in a more comprehensive framework.

Original languageEnglish
Pages (from-to)10,076-10,093
JournalWater Resources Research
Volume54
Issue number12
DOIs
StatePublished - Dec 2018
Externally publishedYes

Funding

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement 641939 (HypoTRAIN) and from the German Research Foundation (DFG) within the Research Training Group Urban Water Interfaces (UWI; GRK 2032/1). Gomez-Velez is funded by the U.S. Department of Energy (DOE), Office of Biological and Environmental Research (BER), as part of BER’s Subsurface Biogeochemistry Research Program (SBR). This contribution originates from the SBR Scientific Focus Area (SFA) at the Pacific Northwest National Laboratory (PNNL) and the U.S. Geological Survey’s River Corridor Powell Center. The authors thank Dörthe Tetzlaff for her valuable suggestions on structuring the manuscript. All data required to reproduce the figures in this paper are available on the database of Leibniz-Institute of Freshwater Ecology and Inland Fisheries (https://www.igb-berlin.de/freshwater-research-and-environmental-database). This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement 641939 (HypoTRAIN) and from the German Research Foundation (DFG) within the Research Training Group Urban Water Interfaces (UWI; GRK 2032/1). Gomez-Velez is funded by the U.S. Department of Energy (DOE), Office of Biological and Environmental Research (BER), as part of BER's Subsurface Biogeochemistry Research Program (SBR). This contribution originates from the SBR Scientific Focus Area (SFA) at the Pacific Northwest National Laboratory (PNNL) and the U.S. Geological Survey's River Corridor Powell Center. The authors thank Dörthe Tetzlaff for her valuable suggestions on structuring the manuscript. All data required to reproduce the figures in this paper are available on the database of Leibniz-Institute of Freshwater Ecology and Inland Fisheries (https://www.igbberlin.de/freshwater-research-andenvironmental-database).

FundersFunder number
SBR Scientific Focus Area
U.S. Department of Energy
U.S. Geological Survey
Biological and Environmental Research
Horizon 2020 Framework Programme
H2020 Marie Skłodowska-Curie Actions641939
Pacific Northwest National Laboratory
Deutsche ForschungsgemeinschaftGRK 2032/1
Horizon 2020
National Forestry and Grassland Administration
Leibniz-Institut für Gewässerökologie und Binnenfischerei

    Fingerprint

    Dive into the research topics of 'Impact of Dynamically Changing Discharge on Hyporheic Exchange Processes Under Gaining and Losing Groundwater Conditions'. Together they form a unique fingerprint.

    Cite this