Journal article
The Fragility of Bedform-Induced Hyporheic Zones: Exploring Impacts of Dynamic Groundwater Table Fluctuations
Water resources research, Vol.60(7), p.n/a
07/2024
DOI: 10.1029/2023WR036706
Abstract
Hyporheic zones are commonly regarded as resilient and enduring interfaces between groundwater and surface water in river corridors. In particular, bedform-induced advective pumping hyporheic exchange (bedform-induced exchange) is often perceived as a relatively persistent mechanism in natural river systems driving water, solutes, and energy exchanges between the channel and its surrounding streambed sediments. Numerous studies have been based on this presumption. To evaluate the persistence of hyporheic zones under varying hydrologic conditions, we use a multi-physics framework to model advective pumping bedform-induced hyporheic exchange in response to a series of seasonal- and event-scale groundwater table fluctuation scenarios, which lead to episodic river-aquifer disconnections and reconnections. Our results suggest that hyporheic exchange is not as ubiquitous as generally assumed. Instead, the bedform-induced hyporheic exchange is restricted to a narrow range of conditions characterized by minor river-groundwater head differences, is intermittent, and can be easily obliterated by minor losing groundwater conditions. These findings shed light on the fragility of bedform-induced hyporheic exchange and have important implications for biogeochemical transformations along river corridors.
The hyporheic zone is a small veneer connecting surface water and groundwater systems, which supports vital ecosystem services along river corridors. The current paradigm assumes this exchange zone is ubiquitous and relatively stable over space and time. Yet, the dynamic nature of the surface and subsurface process driving and modulating the exchange can lead to complex spatiotemporal dynamics where bedform-induced hyporheic zones are only present for short periods or are absent. In this study, we investigated how persistent hyporheic zones are under typical groundwater dynamics. We found that bedform-induced hyporheic zones are not as stable as usually assumed, and their presence is restricted to a narrow range of hydrological conditions. The findings reveal the fragility of hyporheic zones and offer new perspectives to conceptualize river connectivity processes.
We explore bedform-induced hyporheic exchange under various seasonal- and event-scale groundwater table fluctuation scenarios Bedform-induced exchange is intermittent and limited to a narrow range of conditions where river-groundwater head differences are small Bedform-induced exchange fragility highlights the need for better representations of turbulence and turnover drivers in water quality models
Details
- Title: Subtitle
- The Fragility of Bedform-Induced Hyporheic Zones: Exploring Impacts of Dynamic Groundwater Table Fluctuations
- Creators
- L. Wu - Westlake UniversityJ. D. Gomez-Velez - Oak Ridge National LaboratoryL. Li - Westlake UniversityK. C. Carroll - New Mexico State University
- Resource Type
- Journal article
- Publication Details
- Water resources research, Vol.60(7), p.n/a
- DOI
- 10.1029/2023WR036706
- ISSN
- 0043-1397
- eISSN
- 1944-7973
- Publisher
- Amer Geophysical Union
- Number of pages
- 18
- Grant note
- DE-SC0023132 / Research and Development Partnership Pilots Department of Energy Minority Serving Institution Partnership Program (MSIPP) 2142686; 1830172; 2020814; 2312326 / National Science Foundation; National Science Foundation (NSF) DE-SC0023132 / U.S. Department of Energy (DOE); United States Department of Energy (DOE) U.S. Department of Energy, Office of Science, Biological and Environmental Research; United States Department of Energy (DOE)
- Language
- English
- Date published
- 07/2024
- Academic Unit
- Civil and Environmental Engineering
- Record Identifier
- 9984962628902771
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