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1
Ren, Jie, Xiuping Wang, Yinjun Zhou, Bo Chen et Lili Men. « An Analysis of the Factors Affecting Hyporheic Exchange based on Numerical Modeling ». Water 11, no 4 (31 mars 2019) : 665. http://dx.doi.org/10.3390/w11040665.
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The hyporheic zone is a transition zone for the exchange of matter and energy between surface water and subsurface water. The study of trends and sensitivities of bed hyporheic exchanges to the various influencing factors is of great significance. The surface−groundwater flow process was simulated using a multiphysics computational fluid dynamics (CFD) method and compared to previous flume experiments. Based on that, the single-factor effects of flow velocity (u), water depth (H), dune wave height (h), and bed substrate permeability (κ) on hyporheic exchange in the bed hyporheic zone were investigated. The sensitivity analysis of various factors (H, u, dune wavelength (L), h, bed substrate porosity (θ), κ, and the diffusion coefficient of solute molecules (Dm)) in the surface−subsurface water coupling model was done using orthogonal tests. The results indicated that u, h, and κ were positively related, whereas H was negatively related to hyporheic exchange. H and u showed large effects, whereas κ, Dm, and θ had moderate effects, and L and h showed small effects on hyporheic exchange. This study provides valuable references for the protection and recovery of river ecology.
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Mojarrad, Brian Babak, Andrea Betterle, Tanu Singh, Carolina Olid et Anders Wörman. « The Effect of Stream Discharge on Hyporheic Exchange ». Water 11, no 7 (12 juillet 2019) : 1436. http://dx.doi.org/10.3390/w11071436.
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Streambed morphology, streamflow dynamics, and the heterogeneity of streambed sediments critically controls the interaction between surface water and groundwater. The present study investigated the impact of different flow regimes on hyporheic exchange in a boreal stream in northern Sweden using experimental and numerical approaches. Low-, base-, and high-flow discharges were simulated by regulating the streamflow upstream in the study area, and temperature was used as the natural tracer to monitor the impact of the different flow discharges on hyporheic exchange fluxes in stretches of stream featuring gaining and losing conditions. A numerical model was developed using geomorphological and hydrological properties of the stream and was then used to perform a detailed analysis of the subsurface water flow. Additionally, the impact of heterogeneity in sediment permeability on hyporheic exchange fluxes was investigated. Both the experimental and modelling results show that temporally increasing flow resulted in a larger (deeper) extent of the hyporheic zone as well as longer hyporheic flow residence times. However, the result of the numerical analysis is strongly controlled by heterogeneity in sediment permeability. In particular, for homogeneous sediments, the fragmentation of upwelling length substantially varies with streamflow dynamics due to the contribution of deeper fluxes.
3
Wu, Liwen, Jesus D. Gomez-Velez, Stefan Krause, Anders Wörman, Tanu Singh, Gunnar Nützmann et Jörg Lewandowski. « How daily groundwater table drawdown affects the diel rhythm of hyporheic exchange ». Hydrology and Earth System Sciences 25, no 4 (9 avril 2021) : 1905–21. http://dx.doi.org/10.5194/hess-25-1905-2021.
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Abstract. Groundwater table dynamics extensively modify the volume of the hyporheic zone and the rate of hyporheic exchange processes. Understanding the effects of daily groundwater table fluctuations on the tightly coupled flow and heat transport within hyporheic zones is crucial for water resources management. With this aim in mind, a physically based model is used to explore hyporheic responses to varying groundwater table fluctuation scenarios. The effects of different timing and amplitude of groundwater table daily drawdowns under gaining and losing conditions are explored in hyporheic zones influenced by natural flood events and diel river temperature fluctuations. We find that both diel river temperature fluctuations and daily groundwater table drawdowns play important roles in determining the spatiotemporal variability of hyporheic exchange rates, temperature of exfiltrating hyporheic fluxes, mean residence times, and hyporheic denitrification potentials. Groundwater table dynamics present substantially distinct impacts on hyporheic exchange under gaining or losing conditions. The timing of groundwater table drawdown has a direct influence on hyporheic exchange rates and hyporheic buffering capacity on thermal disturbances. Consequently, the selection of aquifer pumping regimes has significant impacts on the dispersal of pollutants in the aquifer and thermal heterogeneity in the sediment.
4
Broecker, Tabea, Katharina Teuber, Vahid Sobhi Gollo, Gunnar Nützmann, Jörg Lewandowski et Reinhard Hinkelmann. « Integral Flow Modelling Approach for Surface Water-Groundwater Interactions along a Rippled Streambed ». Water 11, no 7 (22 juillet 2019) : 1517. http://dx.doi.org/10.3390/w11071517.
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Exchange processes of surface and groundwater are important for the management of water quantity and quality as well as for the ecological functioning. In contrast to most numerical simulations using coupled models to investigate these processes, we present a novel integral formulation for the sediment-water-interface. The computational fluid dynamics (CFD) model OpenFOAM was used to solve an extended version of the three-dimensional Navier–Stokes equations which is also applicable in non-Darcy-flow layers. Simulations were conducted to determine the influence of ripple morphologies and surface hydraulics on the flow processes within the hyporheic zone for a sandy and for a gravel sediment. In- and outflowing exchange fluxes along a ripple were determined for each case. The results indicate that larger grain size diameters, as well as ripple distances, increased hyporheic exchange fluxes significantly. For higher ripple dimensions, no clear relationship to hyporheic exchange was found. Larger ripple lengths decreased the hyporheic exchange fluxes due to less turbulence between the ripples. For all cases with sand, non-Darcy-flow was observed at an upper layer of the ripple, whereas for gravel non-Darcy-flow was recognized nearly down to the bottom boundary. Moreover, the sediment grain sizes influenced also the surface water flow significantly.
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Gooseff, Michael. « Assessment of Hydrologic Transient Storage of Three Streams ». UW National Parks Service Research Station Annual Reports 27 (1 janvier 2003) : 79–80. http://dx.doi.org/10.13001/uwnpsrc.2003.3545.
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Stream sediments are important locations of biogeochemical transformations upon which many stream ecosystem functions depend. Stream water is often exchanged between the stream channel and surrounding subsurface locations - this process is known as hyporheic exchange. While stream water is moving through the hyporheic zone, solutes and nutrients may undergo important chemical reactions that are not possible in the main stream channel. Further, because the hyporheic zone is composed of porous media (sand, sediment, alluvium, etc.), flow inherently slows down and the exchanging water has ample opportunity to interact with mineral grain surfaces and biofilms.
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Earon, Robert, Joakim Riml, Liwen Wu et Bo Olofsson. « Insight into the influence of local streambed heterogeneity on hyporheic-zone flow characteristics ». Hydrogeology Journal 28, no 8 (2 octobre 2020) : 2697–712. http://dx.doi.org/10.1007/s10040-020-02244-5.
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AbstractInteraction between surface water and groundwater plays a fundamental role in influencing aquatic chemistry, where hyporheic exchange processes, distribution of flow paths and residence times within the hyporheic zone will influence the transport of mass and energy in the surface-water/groundwater system. Geomorphological conditions greatly influence hyporheic exchange, and heterogeneities such as rocks and clay lenses will be a key factor for delineating the hyporheic zone. Electrical resistivity tomography (ERT) and ground-penetrating radar (GPR) were used to investigate the streambed along a 6.3-m-long reach in order to characterise geological layering and distinct features which may influence parameters such as hydraulic conductivity. Time-lapse ERT measurements taken during a tracer injection demonstrated that geological features at the meter-scale played a determining role for the hyporheic flow field. The penetration depth of the tracer into the streambed sediment displayed a variable spatial pattern in areas where the presence of highly resistive anomalies was detected. In areas with more homogeneous sediments, the penetration depth was much more uniformly distributed than observed in more heterogeneous sections, demonstrating that ERT can play a vital role in identifying critical hydraulic features that may influence hyporheic exchange processes. Reciprocal ERT measurements linked variability and thus uncertainty in the modelled resistivity to the spatial locations, which also demonstrated larger variability in the tracer penetration depth, likely due to local heterogeneity in the hydraulic conductivity field.
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Mugnai, R., G. Messana et T. Di Lorenzo. « The hyporheic zone and its functions : revision and research status in Neotropical regions ». Brazilian Journal of Biology 75, no 3 (25 septembre 2015) : 524–34. http://dx.doi.org/10.1590/1519-6984.15413.
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AbstractThe hyporheic zone (HZ), as the connecting ecotone between surface- and groundwater, is functionally part of both fluvial and groundwater ecosystems. Its hydrological, chemical, biological and metabolic features are specific of this zone, not belonging truly neither to surface- nor to groundwater. Exchanges of water, nutrients, and organic matter occur in response to variations in discharge and bed topography and porosity. Dynamic gradients exist at all scales and vary temporally. Across all scales, the functional significance of the HZ relates to its activity and connection with the surface stream. The HZ is a relatively rich environment and almost all invertebrate groups have colonized this habitat. This fauna, so-called hyporheos, is composed of species typical from interstitial environment, and also of benthic epigean and phreatic species. The hyporheic microbiocenose consists in bacteria, archaea, protozoa and fungi. The HZ provides several ecosystem services, playing a pivotal role in mediating exchange processes, including both matter and energy, between surface and subterranean ecosystems, functioning as regulator of water flow, benthic invertebrates refuge and place of storage, source and transformation of organic matter. The hyporheic zone is one of the most threatened aquatic environments, being strongly influenced by human activities, and the least protected by legislation worldwide. Its maintenance and conservation is compelling in order to preserve the ecological interconnectivity among the three spatial dimensions of the aquatic environment. Although several researchers addressed the importance of the hyporheic zone early, and most contemporary stream ecosystem models explicitly include it, very little is known about the HZ of Neotropical regions. From a biological standpoint, hyporheos fauna in Neotropical regions are still largely underestimated. This review focuses on a brief presentation of the hyporheic zone and its functions and significance as an ecotone. We also highlighted the key aspects considering also the current status of research in Neotropical regions.
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Hill, Alan R., et Donna J. Lymburner. « Hyporheic zone chemistry and stream-subsurface exchange in two groundwater-fed streams ». Canadian Journal of Fisheries and Aquatic Sciences 55, no 2 (1 février 1998) : 495–506. http://dx.doi.org/10.1139/f97-250.
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Data from two headwater streams in southern Ontario provide support for conceptual models that suggest that hyporheic zone influence on stream nutrient retention is determined by the extent of surface-groundwater exchange and subsurface chemical transformation rates. The hyporheic zone (>10% stream water) was delineated by a chemical mixing equation using differences in background stream and groundwater chloride concentrations and by injections of chloride to stream flow. Good agreement between the two methods confirmed that the extent of stream-groundwater exchanges can be successfully estimated using background conservative ions as a tracer technique. During low stream flows in May-October the depth of the hyporheic zone was 2-15 cm in a 12-m sand-bottom pool, debris dam, pool reach of Glen Major stream and 15-20 cm in a 16-m gravel riffle reach of Duffin Creek. Differences between observed NO3 concentrations and concentrations predicted from background chloride indicated depletion of NO3 in the hyporheic zone at a few locations in Glen Major and at 5-10 cm depth throughout the Duffin Creek reach. NO3 and NH4 injected into stream water were reactive at only a few hyporheic sites in the streams. Upstream-downstream comparisons during injections indicated that stream retention was minor.
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Fang, Yilin, Xingyuan Chen, Jesus Gomez Velez, Xuesong Zhang, Zhuoran Duan, Glenn E. Hammond, Amy E. Goldman, Vanessa A. Garayburu-Caruso et Emily B. Graham. « A multirate mass transfer model to represent the interaction of multicomponent biogeochemical processes between surface water and hyporheic zones (SWAT-MRMT-R 1.0) ». Geoscientific Model Development 13, no 8 (7 août 2020) : 3553–69. http://dx.doi.org/10.5194/gmd-13-3553-2020.
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Abstract. Surface water quality along river corridors can be modulated by hyporheic zones (HZs) that are ubiquitous and biogeochemically active. Watershed management practices often ignore the potentially important role of HZs as a natural reactor. To investigate the effect of hydrological exchange and biogeochemical processes on the fate of nutrients in surface water and HZs, a novel model, SWAT-MRMT-R, was developed coupling the Soil and Water Assessment Tool (SWAT) watershed model and the reaction module from a flow and reactive transport code (PFLOTRAN). SWAT-MRMT-R simulates concurrent nonlinear multicomponent biogeochemical reactions in both the channel water and its surrounding HZs, connecting the channel water and HZs through hyporheic exchanges using multirate mass transfer (MRMT) representation. Within the model, HZs are conceptualized as transient storage zones with distinguished exchange rates and residence times. The biogeochemical processes within HZs are different from those in the channel water. Hyporheic exchanges are modeled as multiple first-order mass transfers between the channel water and HZs. As a numerical example, SWAT-MRMT-R is applied to the Hanford Reach of the Columbia River, a large river in the United States, focusing on nitrate dynamics in the channel water. Major nitrate contaminants entering the Hanford Reach include those from the legacy waste, irrigation return flows (irrigation water that is not consumed by crops and runs off as point sources to the stream), and groundwater seepage resulting from irrigated agriculture. A two-step reaction sequence for denitrification and an aerobic respiration reaction is assumed to represent the biogeochemical transformations taking place within the HZs. The spatially variable hyporheic exchange rates and residence times in this example are estimated with the basin-scale Networks with EXchange and Subsurface Storage (NEXSS) model. Our simulation results show that (1), given a residence time distribution, how the exchange fluxes to HZs are approximated when using MRMT can significantly change the amount of nitrate consumption in HZs through denitrification and (2) source locations of nitrate have a different impact on surface water quality due to the spatially variable hyporheic exchanges.
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Martone, Ivo, Carlo Gualtieri et Theodore Endreny. « Characterization of Hyporheic Exchange Drivers and Patterns within a Low-Gradient, First-Order, River Confluence during Low and High Flow ». Water 12, no 3 (28 février 2020) : 649. http://dx.doi.org/10.3390/w12030649.
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Confluences are nodes in riverine networks characterized by complex three-dimensional changes in flow hydrodynamics and riverbed morphology, and are valued for important ecological functions. This physical complexity is often investigated within the water column or riverbed, while few studies have focused on hyporheic fluxes, which is the mixing of surface water and groundwater across the riverbed. This study aims to understand how hyporheic flux across the riverbed is organized by confluence physical drivers. Field investigations were carried out at a low gradient, headwater confluence between Baltimore Brook and Cold Brook in Marcellus, New York, USA. The study measured channel bathymetry, hydraulic permeability, and vertical temperature profiles, as indicators of the hyporheic exchange due to temperature gradients. Confluence geometry, hydrodynamics, and morphodynamics were found to significantly affect hyporheic exchange rate and patterns. Local scale bed morphology, such as the confluence scour hole and minor topographic irregularities, influenced the distribution of bed pressure head and the related patterns of downwelling/upwelling. Furthermore, classical back-to-back bend planform and the related secondary circulation probably affected hyporheic exchange patterns around the confluence shear layer. Finally, even variations in the hydrological conditions played a role on hyporheic fluxes modifying confluence planform, and, in turn, flow circulation patterns.
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Triska, Frank J., John H. Duff et Ronald J. Avanzino. « Influence of Exchange Flow Between the Channel and Hyporheic Zone on Nitrate Production in a Small Mountain Stream ». Canadian Journal of Fisheries and Aquatic Sciences 47, no 11 (1 novembre 1990) : 2099–111. http://dx.doi.org/10.1139/f90-235.
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Variation in local exchange of flows between the channel and hyporheic zone produced temporally shifting concentration gradients of dissolved oxygen, nitrate, and ammonium in subsurface waters of a small, gravel-cobble bed stream. Channel water advected laterally supplied dissolved oxygen, and groundwater supplied ammonium to support hyporheic nitrification. Nitrate production was highest in sediment slurries from aerobic hyporheic sites, was absent at nearly anoxic sites, and was stopped by nitrification inhibitors (chlorate and nitrapyrin). Ammonium amendment to sediment slurries only slightly enhanced nitrate production indicating that sorption competed with biota for available substrate. Nitrate concentration increased from 75–130 μg N/L during 9 d of ammonium amendment to a hyporheic subsurface flow. Ammonium concentration rose slowly relative to a sulfate tracer initially, and declined slowly after cutoff as ammonium desorbed. Nitrate levels remained elevated for 6 d after cutoff as desorbed ammonium became biotically available. Interactions between the channel's hydrology, lithology, and biology such as we observed in nitrate production are probably more common than reported. However, the magnitude of the resulting nutrient flux will depend on factors which determine the depth and lateral extension of suitable hyporheic habitat.
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Yao, Congcong, Chengpeng Lu, Wei Qin et Jiayun Lu. « Field Experiments of Hyporheic Flow Affected by a Clay Lens ». Water 11, no 8 (3 août 2019) : 1613. http://dx.doi.org/10.3390/w11081613.
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As a typical water exchange of surface water and groundwater, hyporheic flow widely exists in streambeds and is significantly affected by the characteristics of sediment and surface water. In this study, a low-permeability clay lens was chosen to investigate the influence of the streambed heterogeneity on the hyporheic flow at a river section of the Xin’an River in Anhui Province, China. A 2D sand tank was constructed to simulate the natural streambed including a clay lens under different velocity of surface water velocity. Heat tracing was used in this study. In particular, six analytical solutions based on the amplitude ratio and phase shift of temperatures were applied to calculate the vertical hyporheic flux. The results of the six methods ranged from −102.4 to 137.5 m/day and showed significant spatial differences. In view of the robustness of the calculations and the rationality of the results, the amplitude ratio method was much better than the phase shift method. The existence of the clay lens had a significant influence on the hyporheic flow. Results shows that the vertical hyporheic flux in the model containing a clay lens was lower than that for the blank control, and the discrepancy of the hyporheic flow field on both sides of the lens was obvious. Several abnormal flow velocity zones appeared around the clay lens where the local hyporheic flow was suppressed or generally enhanced. The hyporheic flow fields at three test points had mild changes when the lens was placed in a shallow layer of the model, indicating that the surface water velocity only affect the hyporheic flow slightly. With the increasing depth of the clay lens, the patterns of the hyporheic flow fields at all test points were very close to those of the hyporheic flow field without a clay lens, indicating that the influence of surface water velocity on hyporheic flow appeared gradually. A probable maximum depth of the clay lens was 30 to 40 cm, which approached the bottom of the model and a clay lens buried lower than this maximum would not affect the hyporheic flow any more. Influenced by the clay lens, hyporheic flow was hindered or enhanced in different regions of streambed, which was also depended on the depth of lens and surface water velocity. Introducing a two-dimensional sand tank model in a field test is an attempt to simulate a natural streambed and may positively influence research on hyporheic flow.
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Mehedi, Md Abdullah Al, Munshi Md Shafwat Yazdan, Md Tanvir Ahad, Wisdom Akatu, Raaghul Kumar et Ashiqur Rahman. « Quantifying Small-Scale Hyporheic Streamlines and Resident Time under Gravel-Sand Streambed Using a Coupled HEC-RAS and MIN3P Model ». Eng 3, no 2 (13 juin 2022) : 276–300. http://dx.doi.org/10.3390/eng3020021.
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Distribution of the water flow path and residence time (HRT) in the hyporheic zone is a pivotal aspect in anatomizing the transport of environmental contaminants and the metabolic rates at the groundwater and surface water interface in fluvial habitats. Due to high variability in material distribution and composition in streambed and subsurface media, a pragmatic model setup in the laboratory is strenuous. Moreover, investigation of an individual streamline cannot be efficiently executed in laboratory experiments. However, an automated generation of water flow paths, i.e., streamlines in the hyporheic zone with a range of different streambed configurations could lead to a greater insight into the behavior of hyporheic water flow. An automated approach to quantifying the water flow in hyporheic zone is developed in this study where the surface water modeling tool, HER-RAS, and subsurface water flow modelling code, MIN3P, are coupled. A 1m long stream with constant water surface elevation of 2 cm to generate hydraulic head gradients and a saturated subsurface computational space with the dimensions of x:y:z = 1:0.1:0.1 m is considered to analyze the hyporheic exchange. Response in the hyporheic streamlines and residence time due to small-scale changes in the gravel-sand streambed were analyzed. The outcomes of the model show that the size, shape, and distribution of the gravel and sand portions have a significant influence on the hyporheic flow path and HRT. A high number and length of the hyporheic flow path are found in case of the highly elevated portion of gravel pieces. With the increase in the base width of gravel pieces, the length of hyporheic flow path and HRT decreases. In the case of increased amounts of gravel and sand portions on the streambed, both the quantity and length of the hyporheic flow path are reduced significantly.
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Zhang, Guotao, Jinxi Song, Ming Wen, Junlong Zhang, Weiwei Jiang, Liping Wang, Feihe Kong et Yuanyuan Wang. « Effect of bank curvatures on hyporheic water exchange at meter scale ». Hydrology Research 48, no 2 (6 juin 2016) : 355–69. http://dx.doi.org/10.2166/nh.2016.046.
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The micro-topography feature of a riverine system is a controlling attribute to induce the change of patterns and magnitudes of hyporheic water exchange. The study aims to determine how hyporheic water exchange is affected by the bank curvatures of test points at meter scale. A one-dimensional heat steady-state transport model was applied to determine patterns and magnitudes of vertical hyporheic water exchange in January and July 2015. The bank curvatures were calculated based on the curvature formula. The results demonstrate that vertical water exchange patterns of all test points were upwards during the two test periods, and the higher vertical fluxes mostly occurred in January 2015. Large curvatures for either sides of convex banks in the two periods resulted in higher vertical water exchange fluxes, and the significantly higher vertical fluxes occurred near the apex of bends. Additionally, a flow pattern from river bank discharging into stream was derived during the campaign in July 2015, and significantly higher fluxes were obtained along the straight bank where more riparian vegetation was adjacent to the bank/water interface. It can be suggested that the bank curvatures and riparian vegetation are considered the crucial attributes influencing hyporheic water exchange.
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Liu, Yuanhong, Corey D. Wallace, Yaoquan Zhou, Reza Ershadnia, Faranak Behzadi, Dipankar Dwivedi, Lianqing Xue et Mohamad Reza Soltanian. « Influence of Streambed Heterogeneity on Hyporheic Flow and Sorptive Solute Transport ». Water 12, no 6 (28 mai 2020) : 1547. http://dx.doi.org/10.3390/w12061547.
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The subsurface region where river water and groundwater actively mix (the hyporheic zone) plays an important role in conservative and reactive solute transport along rivers. Deposits of high-conductivity (K) sediments along rivers can strongly control hyporheic processes by channeling flow along preferential flow paths wherever they intersect the channel boundary. Our goal is to understand how sediment heterogeneity influences conservative and sorptive solute transport within hyporheic zones containing high- and low-K sediment facies types. The sedimentary architecture of high-K facies is modeled using commonly observed characteristics (e.g., volume proportion and mean length), and their spatial connectivity is quantified to evaluate its effect on hyporheic mixing dynamics. Numerical simulations incorporate physical and chemical heterogeneity by representing spatial variability in both K and in the sediment sorption distribution coefficient ( K d ). Sediment heterogeneity significantly enhances hyporheic exchange and skews solute breakthrough behavior, while in homogeneous sediments, interfacial flux and solute transport are instead controlled by geomorphology and local-scale riverbed topographies. The hyporheic zone is compressed in sediments with high sorptive capacity, which limits solute interactions to only a small portion of the sedimentary architecture and thus increases retention. Our results have practical implications for groundwater quality, including remediation strategies for contaminants of emerging concern.
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Kasahara, Tamao, et Steven M. Wondzell. « Geomorphic controls on hyporheic exchange flow in mountain streams ». Water Resources Research 39, no 1 (janvier 2003) : SBH 3–1—SBH 3–14. http://dx.doi.org/10.1029/2002wr001386.
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Siergieiev, D., L. Ehlert, T. Reimann, A. Lundberg et R. Liedl. « Modelling hyporheic processes for regulated rivers under transient hydrological and hydrogeological conditions ». Hydrology and Earth System Sciences 19, no 1 (16 janvier 2015) : 329–40. http://dx.doi.org/10.5194/hess-19-329-2015.
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Abstract. Understanding the effects of major hydrogeological controls on hyporheic exchange and bank storage is essential for river water management, groundwater abstraction, restoration and ecosystem sustainability. Analytical models cannot adequately represent complex settings with, for example, transient boundary conditions, varying geometry of surface water–groundwater interface, unsaturated and overland flow, etc. To understand the influence of parameters such as (1) sloping river banks, (2) varying hydraulic conductivity of the riverbed and (3) different river discharge wave scenarios on hyporheic exchange characteristics such as (a) bank storage, (b) return flows and (c) residence time, a 2-D hydrogeological conceptual model and, subsequently, an adequate numerical model were developed. The numerical model was calibrated against observations in the aquifer adjacent to the hydropower-regulated Lule River, northern Sweden, which has predominantly diurnal discharge fluctuations during summer and long-lasting discharge peaks during autumn and winter. Modelling results revealed that bank storage increased with river wave amplitude, wave duration and smaller slope of the river bank, while maximum exchange flux decreased with wave duration. When a homogeneous clogging layer covered the entire river–aquifer interface, hydraulic conductivity positively affected bank storage. The presence of a clogging layer with hydraulic conductivity < 0.001 m d−1 significantly reduced the exchange flows and virtually eliminated bank storage. The bank storage return/fill time ratio was positively related to wave amplitude and the hydraulic conductivity of the interface and negatively to wave duration and bank slope. Discharge oscillations with short duration and small amplitude decreased bank storage and, therefore, the hyporheic exchange, which has implications for solute fluxes, redox conditions and the potential of riverbeds as fish-spawning locations. Based on these results, river regulation strategies can be improved by considering the effect of certain wave event configurations on hyporheic exchange to ensure harmonious hydrogeochemical functioning of the river–aquifer interfaces and related ecosystems.
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Siergieiev, D., L. Ehlert, T. Reimann, A. Lundberg et R. Liedl. « Modelling hyporheic processes for regulated rivers under transient hydrological and hydrogeological conditions ». Hydrology and Earth System Sciences Discussions 11, no 8 (5 août 2014) : 9327–59. http://dx.doi.org/10.5194/hessd-11-9327-2014.
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Abstract. Understanding the effects of major hydrogeological controls on hyporheic exchange and bank storage is essential for river water management, groundwater abstraction, restoration and ecosystem sustainability. Analytical models cannot adequately represent complex settings with, for example, transient boundary conditions, varying geometry of surface water–groundwater interface, unsaturated and overland flow, etc. To understand the influence of parameters such as (1) sloping river banks, (2) varying hydraulic conductivity of the riverbed and (3) different river discharge wave scenarios on hyporheic exchange characteristics such as (a) bank storage, (b) return flows and (c) residence time, a 2-D hydrogeological conceptual model and, subsequently, an adequate numerical model were developed. The numerical model was calibrated against observations in the aquifer adjacent to the hydropower regulated Lule River, Northern Sweden, which has predominantly diurnal discharge fluctuations during summer and long-lasting discharge peaks during autumn and winter. Modelling results revealed that bank storage increased with river wave amplitude, wave duration and smaller slope of the river bank, while maximum exchange flux decreased with wave duration. When a homogeneous clogging layer covered the entire river–aquifer interface, hydraulic conductivity positively affected bank storage. The presence of a clogging layer with hydraulic conductivity < 0.001 m d−1 significantly reduced the exchange flows and virtually eliminated bank storage. The bank storage return/fill time ratio was positively related to wave amplitude and the hydraulic conductivity of the interface and negatively to wave duration and bank slope. Discharge oscillations with short duration and small amplitude decreased bank storage and, therefore, the hyporheic exchange, which has implications for solute fluxes, redox conditions and the spawning potential of riverbeds. Based on these results, river regulation strategies can be improved by considering the effect of certain wave event configurations on hyporheic exchange to ensure harmonious hydrogeochemical functioning of the river–aquifer interfaces and related ecosystems.
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Nawalany, Marek, Grzegorz Sinicyn, Maria Grodzka-Łukaszewska et Dorota Mirosław-Świątek. « Groundwater–Surface Water Interaction—Analytical Approach ». Water 12, no 6 (23 juin 2020) : 1792. http://dx.doi.org/10.3390/w12061792.
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Modelling of water flow in the hyporheic zone and calculations of water exchange between groundwater and surface waters are important issues in modern environmental research. The article presents the Analytical Hyporheic Flux approach (AHF) permitting calculation of the amount of water exchange in the hyporheic zone, including vertical water seepage through the streambed and horizontal seepage through river banks. The outcome of the model, namely water fluxes, is compared with the corresponding results from the numerical model SEEP2D and simple Darcy-type model. The errors of the AHF model, in a range of 11–16%, depend on the aspect ratio of water depth to river width, and the direction of the river–aquifer water exchange, i.e., drainage or infiltration. The AHF model errors are significantly lower compared to the often-used model based on vertical water seepage through the streambed described by Darcy’s law.
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Singh, Tanu, Liwen Wu, Jesus D. Gomez‐Velez, Jörg Lewandowski, David M. Hannah et Stefan Krause. « Dynamic Hyporheic Zones : Exploring the Role of Peak Flow Events on Bedform‐Induced Hyporheic Exchange ». Water Resources Research 55, no 1 (janvier 2019) : 218–35. http://dx.doi.org/10.1029/2018wr022993.
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Wu, Guangdong, Xiao Zhang et Jijun Xu. « Spatial Variability Pattern of Hyporheic Exchange in a braided River ». MATEC Web of Conferences 246 (2018) : 01098. http://dx.doi.org/10.1051/matecconf/201824601098.
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The streambed flux is variable in space; the spatial variability results in part from bedforms, but few works on streambed fluxes in channels with strongly abrupt varying bedforms are carried out. Heat as a tracer to delineate the streambed flux pattern has been widely adopted in numerous fields. In this paper, a braided channel with complicated topography was selected as study site, where the temperature was monitored. One-dimensional (1-D) analytical method based on the amplitude attenuation (Ar) and 1-D numerical method were used to interpret the temperature. As a result, streambed fluxes of a total of 50 sites in the braided channel are obtained. From the results we can know the magnitude and direction of streamed flow velocity are spatially variable, even within a 1-m distance. Then, this study summarizes five bedform-driven flux patterns: ① downward flow driven by the head difference between groundwater and stream, ② downward flow related to a meter-scale pool, ③ a transition from upward to downward flow associated with a centimeter-scale riffle, ④ horizontal flow in braided bars and ⑤ upward flow driven by vegetation roots. Overall, multiple physical mechanisms together contributed to the complex streambed flow system, which reflected great challenges for the scaling up of point-in-space seepage flux.
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Kasahara, Tamao, et Alan R. Hill. « Effects of rifflestep restoration on hyporheic zone chemistry in N-rich lowland streams ». Canadian Journal of Fisheries and Aquatic Sciences 63, no 1 (1 janvier 2006) : 120–33. http://dx.doi.org/10.1139/f05-199.
Texte intégralRésumé :
Stream restoration projects that aim to rehabilitate ecosystem health have not considered surfacesubsurface linkages, although stream water and groundwater interaction has an important role in sustaining stream ecosystem functions. The present study examined the effect of constructed riffles and a step on hyporheic exchange flow and chemistry in restored reaches of several N-rich agricultural and urban streams in southern Ontario. Hydrometric data collected from a network of piezometers and conservative tracer releases indicated that the constructed riffles and steps were effective in inducing hyporheic exchange. However, despite the use of cobbles and boulders in the riffle construction, high stream dissolved oxygen (DO) concentrations were depleted rapidly with depth into the hyporheic zones. Differences between observed and predicted nitrate concentrations based on conservative ion concentration patterns indicated that these hyporheic zones were also nitrate sinks. Zones of low hydraulic conductivity and the occurrence of interstitial fines in the restored cobble-boulder layers suggest that siltation and clogging of the streambed may reduce the downwelling of oxygen- and nitrate-rich stream water. Increases in streambed DO levels and enhancement of habitat for hyporheic fauna that result from rifflestep construction projects may only be temporary in streams that receive increased sediment and nutrient inputs from urban areas and croplands.
23
Ikard, Scott J., Andrew P. Teeple, Jason D. Payne, Gregory P. Stanton et J. Ryan Banta. « New Insights on Scale-dependent Surface-Groundwater Exchange from a Floating Self-potential Dipole ». Journal of Environmental and Engineering Geophysics 23, no 2 (juin 2018) : 261–87. http://dx.doi.org/10.2113/jeeg23.2.261.
Texte intégralRésumé :
In south-central Texas the lower Guadalupe River has incised into the outcrop of the Carrizo-Wilcox aquifer. The river and the aquifer are hydraulically connected across the outcrop, although the connectivity is obscured at the surface by alluvium and surface-water and groundwater exchange dynamics are currently poorly understood. To investigate surface-water and groundwater exchange dynamics between the lower Guadalupe River and the Carrizo-Wilcox aquifer, a geophysical study was completed along a 14.86 km reach of the river by using water-borne gradient self-potential (SP) profiling and two-dimensional direct-current electric resistivity tomography. This paper explores the applicability of these water-borne geoelectric methods in delineating gaining and losing channel reaches, and demonstrates that geoelectric signals in the form of total electric field strength can be logged with an electric dipole and decomposed into component SP signals depicting regional and local groundwater flow patterns attributable to regional and localized hydraulic gradients. Localized SP anomalies of several tens of millivolts, indicative of hyporheic exchange flows, are observed and superimposed upon a 124 mV regional SP anomaly indicative of ambient groundwater exchange flows between the river and the aquifer. The observed SP signals are interpreted through two-dimensional finite-element modeling of streaming potentials attributable to ambient groundwater exchange and hyporheic exchange flow patterns. Variables of the channel environment such as temperature and concentration gradients, depth, and velocity are considered and subsequently eliminated as alternative sources of the SP signals that are presented.
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Surfleet, Christopher, et Justin Louen. « The Influence of Hyporheic Exchange on Water Temperatures in a Headwater Stream ». Water 10, no 11 (9 novembre 2018) : 1615. http://dx.doi.org/10.3390/w10111615.
Texte intégralRésumé :
A headwater stream in coastal California was used to evaluate the temperature response of effective shade reduction. Spatial distribution of stream water temperatures for summer low-flow conditions (<0.006 m3 s−1) were highly correlated with net radiation and advective heat transfers from hyporheic exchange and subsequent streambed conduction. Using a heat budget model, mean maximum stream water temperatures were predicted to increase by 1.7 to 2.2 °C for 50% and 0% effective shade scenarios, respectively, at the downstream end of a 300 m treatment reach. Effects on mean maximum stream water temperature changes, as water flowed downstream through a 500 m shaded reach below the treatment reach, were reduced by 52 to 30% from the expected maximum temperature increases under the 50% and 0% effective shade scenarios, respectively. Maximum stream water temperature change predicted by net radiation heating alone was greater than measured and heat-budget-estimated temperatures. When the influence of hyporheic water exchange was combined with net radiation predictions, predicted temperatures were similar to measured and heat-budget-predicted temperatures. Results indicate that advective heat transfers associated with hyporheic exchange can promote downstream cooling following stream water temperature increases from shade reduction in a headwater stream with cascade, step-pool, and large woody debris forced-pool morphology.
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Westhoff, M. C., T. A. Bogaard et H. H. G. Savenije. « Quantifying spatial and temporal discharge dynamics of an event in a first order stream, using distributed temperature sensing ». Hydrology and Earth System Sciences 15, no 6 (24 juin 2011) : 1945–57. http://dx.doi.org/10.5194/hess-15-1945-2011.
Texte intégralRésumé :
Abstract. Understanding the spatial distribution of discharge can be important for water quality and quantity modeling. Non-steady flood waves can, particularly as a result of short high intensity summer rainstorms, influence small headwater streams significantly. The aim of this paper is to quantify the spatial and temporal dynamics of stream flow in a headwater stream during a summer rainstorm. These dynamics include gains and losses of stream water, the effect of bypasses that become active and hyporheic exchange fluxes that may vary over time as a function of discharge. We use an advection-dispersion model coupled with an energy balance model to simulate in-stream water temperature, which we compare with high resolution temperature observations obtained with Distributed Temperature Sensing. This model was used as a learning tool to stepwise unravel the complex puzzle of in-stream processes subject to varying discharge. Hypotheses were tested and rejected, which led to more insight in the spatial and temporal dynamics in discharge and hyporheic exchange processes. We showed that, for the studied stream infiltration losses increase during a small rain event, while gains of water remained constant over time. We conclude that, eventually, part of the stream water bypassed the main channel during peak discharge. It also seems that hyporheic exchange varies with varying discharge in the first 250 m of the stream; while further downstream it remains constant. Because we relied on solar radiation as the main energy input, we were only able to apply this method during a small summer storm and low flow conditions. However, when additional (artificial) energy is available, the presented method is also applicable in larger streams, during higher flow conditions or longer storms.
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Westhoff, M. C., T. A. Bogaard et H. H. G. Savenije. « Quantifying spatial and temporal discharge dynamics of an event in a first order stream, using Distributed Temperature Sensing ». Hydrology and Earth System Sciences Discussions 8, no 2 (1 mars 2011) : 2175–205. http://dx.doi.org/10.5194/hessd-8-2175-2011.
Texte intégralRésumé :
Abstract. Understanding spatial distribution of discharge can be important for water quality and quantity modeling. Non-steady flood waves can influence small headwater streams significantly, particularly as a result of short high intensity summer rainstorms. The aim of this paper is to quantify the spatial and temporal dynamics of stream flow in a headwater catchment during a summer rainstorm. These dynamics include gains and losses of stream water, the effect of bypasses that become active and hyporheic exchange fluxes that may vary over time as a function of discharge. We use an advection-dispersion model coupled with an energy balance model to simulate in-stream water temperature, which we confront with high resolution temperature observations obtained with Distributed Temperature Sensing. This model was used as a learning tool to stepwise unravel the complex puzzle of in-stream processes subject to varying discharge. Hypotheses were tested and rejected, which led to more insight in spatial and temporal dynamics in discharge and hyporheic exchange processes. We showed that infiltration losses increase during a rain event, while gains of water remained constant over time. We conclude that, eventually, part of the stream water bypassed the main channel during peak discharge. It also seems that hyporheic exchange varies with varying discharge in the first 250 of the stream; while further downstream it remains constant. Because we relied on solar radiation as the main energy input, we were only able to apply this method during a small event and low flow. However, when additional (artificial) energy is available, the presented method is also applicable in larger streams, or during higher flow conditions.
27
Marttila, H., S. Tammela, K. R. Mustonen, P. Louhi, T. Muotka, H. Mykrä et B. Kløve. « Contribution of flow conditions and sand addition on hyporheic zone exchange in gravel beds ». Hydrology Research 50, no 3 (27 février 2019) : 878–85. http://dx.doi.org/10.2166/nh.2019.099.
Texte intégralRésumé :
Abstract We conducted a series of tracer test experiments in 12 outdoor semi-natural flumes to assess the effects of variable flow conditions and sand addition on hyporheic zone conditions in gravel beds, mimicking conditions in headwater streams under sediment pressure. Two tracer methods were applied in each experiment: 2–5 tracer-pulse tests were conducted in all flumes and pulses were monitored at three distances downstream of the flume inlet (0 m, 5 m and 10 m, at bed surface), and in pipes installed into the gravel bed at 5 m and 10 m distances. The tracer breakthrough curves (total of 120 tracer injections) were then analysed with a one-dimensional solute transport model (OTIS) and compared with data from the gravel pipes in point-dilution pulse tests. Sand addition had a strong negative effect on horizontal fluxes (qh), whereas the fraction of the median travel time due to transient storage (F200) was determined more by flow conditions. These results suggest that even small additions of sand can modify the hyporheic zone exchange in gravel beds, thus making headwater streams with low sediment transport capacity particularly vulnerable to sediments transported into the stream from catchment land use activities.
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Bickel, Tobias O., et Gerard P. Closs. « Impact of Didymosphenia geminata on hyporheic conditions in trout redds : reason for concern ? » Marine and Freshwater Research 59, no 11 (2008) : 1028. http://dx.doi.org/10.1071/mf08011.
Texte intégralRésumé :
Didymosphenia geminata (Lyngbye) Schmidt (commonly called didymo) is an invasive diatom and of concern to fisheries managers in North America and more recently New Zealand. Didymo grows in thick mats in several river systems on the South Island of New Zealand, often smothering entire river beds. Salmonid eggs, deposited in gravel nests (redds), depend on constant water exchange across the riverbed to provide oxygen-rich water for development. Thick didymo mats might restrict the flow of oxygen-rich water into spawning gravels, resulting in increased egg mortality and reduced trout recruitment. The present study measured hyporheic hydraulic conditions in trout redds with varying didymo cover in the Clutha River catchment, South Island, New Zealand. Didymo cover had no significant effects on several hydraulic variables (flow into the substrate, hydraulic conductivity and hyporheic oxygen concentration). However, there was a significant difference in the potential surface water–groundwater exchange between sites, suggesting some effect of didymo on hydraulic conditions. Considering the limited number of replicates, the impact of didymo on trout redds in the Clutha River cannot be excluded. The present study highlights the need for further research on the possible effects of didymo on important surface water–groundwater exchange processes.
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Packman, Aaron I., et Mashfiqus Salehin. « Relative roles of stream flow and sedimentary conditions in controlling hyporheic exchange ». Hydrobiologia 494, no 1-3 (mars 2003) : 291–97. http://dx.doi.org/10.1023/a:1025403424063.
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Kim, Heejung, et Kang-Kun Lee. « Effect of vertical flow exchange on microbial community distributions in hyporheic zones ». Episodes 42, no 1 (8 mars 2019) : 1–16. http://dx.doi.org/10.18814/epiiugs/2019/019001.
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Stubbington, Rachel. « The hyporheic zone as an invertebrate refuge : a review of variability in space, time, taxa and behaviour ». Marine and Freshwater Research 63, no 4 (2012) : 293. http://dx.doi.org/10.1071/mf11196.
Texte intégralRésumé :
The hyporheic zone is a potential refuge that can promote persistence of benthic invertebrates during adverse conditions in surface streams. For decades, changes in invertebrate depth distribution have been investigated in relation to flood, low flow and drying events, but evidence for use of the hyporheic refuge remains equivocal. This review examines the evidence for the hyporheic zone’s refugial role during adverse hydrological conditions. Refuge potential is influenced by determinants in four categories. First, refuge use varies spatially in relation to physical habitat parameters, including sediment porosity and hydrologic exchange. Second, refuge use is temporally variable and reflects disturbance characteristics including rate of onset. Third, refuge use is taxon-specific, depending on a range of morphological, behavioural and physiological traits. Fourth, the behaviours governing refuge use vary, with both active migrations and passive habitat use playing important roles in community persistence. These four determinants interact to influence refuge use; for example, the physical habitat providing an adequate refuge will vary between taxa. Despite this variability, the hyporheic zone is an important component in the suite of refuges that facilitate community resilience to disturbance events. As such, its ecological integrity should be safeguarded through sensitive management and effective rehabilitation schemes.
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Kruegler, James, Jesus Gomez-Velez, Laura K. Lautz et Theodore A. Endreny. « Dynamic Evapotranspiration Alters Hyporheic Flow and Residence Times in the Intrameander Zone ». Water 12, no 2 (5 février 2020) : 424. http://dx.doi.org/10.3390/w12020424.
Texte intégralRésumé :
Hyporheic zones (HZs) influence biogeochemistry at the local reach scale with potential implication for water quality at the large catchment scale. The characteristics of the HZs (e.g., area, flux rates, and residence times) change in response to channel and aquifer physical properties, as well as to transient perturbations in the stream–aquifer system such as floods and groundwater withdraws due to evapotranspiration (ET) and pumping. In this study, we use a numerical model to evaluate the effects of transient near-stream evapotranspiration (ET) on the area, exchange flux, and residence time (RT) of sinuosity-induced HZs modulated by regional groundwater flow (RGF). We found that the ET fluxes (up to 80 mm/day) consistently increased HZ area and exchange flux, and only increased RTs when the intensity of regional groundwater flow was low. Relative to simulations without ET, scenarios with active ET had more than double HZ area and exchange flux and about 20% longer residence times (as measured by the median of the residence time distribution). Our model simulations show that the drawdown induced by riparian ET increases the net flux of water from the stream to the nearby aquifer, consistent with field observations. The results also suggest that, along with ET intensity, the magnitude of the HZ response is influenced by the modulating effect of both gaining and losing RGF and the sensitivity of the aquifer to daily cycles of ET withdrawal. This work highlights the importance of representing near-stream ET when modeling sinuosity-induced hyporheic zones, as well as the importance of including riparian vegetation in efforts to restore the ecosystem functions of streams.
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Huang, Tao, Wilfred M. Wollheim et Stephen H. Jones. « Removal of Fecal Indicator Bacteria by River Networks ». Water 14, no 4 (17 février 2022) : 617. http://dx.doi.org/10.3390/w14040617.
Texte intégralRésumé :
Fecal contamination is a significant source of water quality impairment globally. Aquatic ecosystems can provide an important ecosystem service of fecal contamination removal. Understanding the processes that regulate the removal of fecal contamination among river networks across flow conditions is critical. We applied a river network model, the Framework for Aquatic Modeling in the Earth System (FrAMES-Ecoli), to quantify removal of fecal indicator bacteria by river networks across flow conditions during summers in a series of New England watersheds of different characteristics. FrAMES-Ecoli simulates sources, transport, and riverine removal of Escherichia coli (E. coli). Aquatic E. coli removal was simulated in both the water column and the hyporheic zone, and is a function of hydraulic conditions, flow exchange rates with the hyporheic zone, and die-off in each compartment. We found that, at the river network scale during summers, removal by river networks can be high (19–99%) with variability controlled by hydrologic conditions, watershed size, and distribution of sources in the watershed. Hydrology controls much of the variability, with 68–99% of network scale inputs removed under base flow conditions and 19–85% removed during storm events. Removal by the water column alone could not explain the observed pattern in E. coli, suggesting that processes such as hyporheic removal must be considered. These results suggest that river network removal of fecal indicator bacteria should be taken into consideration in managing fecal contamination at critical downstream receiving waters.
34
Baxter, Colden V., et F. Richard Hauer. « Geomorphology, hyporheic exchange, and selection of spawning habitat by bull trout (Salvelinus confluentus) ». Canadian Journal of Fisheries and Aquatic Sciences 57, no 7 (1 juillet 2000) : 1470–81. http://dx.doi.org/10.1139/f00-056.
Texte intégralRésumé :
The distribution and abundance of bull trout (Salvelinus confluentus) spawning were affected by geomorphology and hyporheic groundwater - stream water exchange across multiple spatial scales in streams of the Swan River basin, northwestern Montana. Among spawning tributary streams, the abundance of bull trout redds increased with increased area of alluvial valley segments that were longitudinally confined by geomorphic knickpoints. Among all valley segment types, bull trout redds were primarily found in these bounded alluvial valley segments, which possessed complex patterns of hyporheic exchange and extensive upwelling zones. Bull trout used stream reaches for spawning that were strongly influenced by upwelling. However, within these selected reaches, bull trout redds were primarily located in transitional bedforms that possessed strong localized downwelling and high intragravel flow rates. The changing relationship of spawning habitat selection, in which bull trout selected upwelling zones at one spatial scale and downwelling zones at another spatial scale, emphasizes the importance of considering multiple spatial scales within a hierarchical geomorphic context when considering the ecology of this species or plans for bull trout conservation and restoration.
35
Harmon, Russell S., Deborah L. Leslie, W. Berry Lyons, Kathleen A. Welch et Diane M. McKnight. « Diurnal chemistry of two contrasting stream types, Taylor Valley, McMurdo Dry Valley Region, Antarctica ». E3S Web of Conferences 98 (2019) : 01020. http://dx.doi.org/10.1051/e3sconf/20199801020.
Texte intégralRésumé :
Numerous ephemeral streams flow within the McMurdo Dry Valley Region of Antarctica that transport glacial meltwater to perennially ice-covered, closed-basin lakes during the austral summer. The diurnal behavior for two Taylor Valley streams of different character was examined during the summer of 2010-11. Andersen Creek is a short, 1st-order proglacial stream, whereas Von Guerard Stream is a long, high-order stream with an extensive hyporheic zone that has a substantial cyanobacterial algal mat community in its middle reaches. Both streams display strong daily cycles for temperature, electrical conductivity, dissolved oxygen, and pH. Conductivity varies in concert with flow, with solute dilution occurring during the daily high-flow pulse. Dissolved oxygen co-varies strongly with pH at Andersen Creek but not for Von Guerard Stream. Each stream has a distinct geochemical character that for Andersen Creek is a direct reflection of its glacial source, unmodified by secondary effects, whereas that for Von Guerard Stream is modulated by its resident algal mat community and through extensive hyporheic zone interaction and exchange.
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Crispell, Jill K., et Theodore A. Endreny. « Hyporheic exchange flow around constructed in-channel structures and implications for restoration design ». Hydrological Processes 23, no 8 (15 avril 2009) : 1158–68. http://dx.doi.org/10.1002/hyp.7230.
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Rickel, Ariel, Beth Hoagland, Alexis Navarre-Sitchler et Kamini Singha. « Seasonal shifts in surface water-groundwater connections in a ferricrete-impacted stream estimated from electrical resistivity ». GEOPHYSICS 86, no 5 (27 juillet 2021) : WB175—WB187. http://dx.doi.org/10.1190/geo2020-0599.1.
Texte intégralRésumé :
The efficacy of the hyporheic zone (HZ) — where surface water and groundwater mix — for processing nutrients or the uptake of metals is dependent on the streambed hydraulic conductivity and stream discharge, among other characteristics. Here, we have explored electrical resistivity tomography (ERT) of hyporheic exchange in Cement Creek near Silverton, Colorado, which is affected by ferricrete precipitation. To quantify flows through the HZ, we have conducted 4 h salt injection tracer tests and collected time-lapse ERT of the streambed and banks of Cement Creek at high and low flow. We have installed piezometers to conduct slug tests, which suggest a low-permeability zone at 44 cm depth likely composed of ferricrete that cemented the cobbles together. Based on the ERT, the tracer released into the stream is constrained within the shallow streambed with little subsurface flow through the banks. The tracer is detected in the HZ for a longer time at high flow compared to low flow, suggesting that more flow paths were available to connect the stream to the HZ. The tracer is confined above the ferricrete layer during the high- and low-flow tests. Mass transfer and storage area parameters are calculated from combined analysis of apparent bulk conductivity derived from ERT and numerical modeling of the tracer breakthrough curves. The hyporheic storage area estimated at low discharge ([Formula: see text]) is smaller than that at high discharge ([Formula: see text]) and residence times are 2.7 h at low discharge and 4.1 h at high discharge. During high discharge, in-stream breakthrough curves display slower breakthrough and longer tails, which is consistent with the time-lapse electrical inversions and 1D transport with inflow and storage modeling. Our findings indicate that ferricrete reduces the hydraulic conductivity of the streambed and limits the areal extent of the HZ, which may lower the potential for pollutant attenuation from the metal-rich waters of Cement Creek.
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Gomez-Velez, J. D., J. L. Wilson, M. B. Cardenas et J. W. Harvey. « Flow and Residence Times of Dynamic River Bank Storage and Sinuosity-Driven Hyporheic Exchange ». Water Resources Research 53, no 10 (octobre 2017) : 8572–95. http://dx.doi.org/10.1002/2017wr021362.
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Fox, A., G. Laube, C. Schmidt, J. H. Fleckenstein et S. Arnon. « The effect of losing and gaining flow conditions on hyporheic exchange in heterogeneous streambeds ». Water Resources Research 52, no 9 (septembre 2016) : 7460–77. http://dx.doi.org/10.1002/2016wr018677.
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Li, Yong, Na Li, Jiacheng Feng, Jianing Qian et Yajie Shan. « Temporal Temperature Distribution in Shallow Sediments of a Large Shallow Lake and Estimated Hyporheic Flux Using VFLUX 2 Model ». Water 13, no 3 (26 janvier 2021) : 300. http://dx.doi.org/10.3390/w13030300.
Texte intégralRésumé :
Identifying and quantifying exchange flux across sediment-water interface is crucial when considering water and nutrient contributions to a eutrophic lake. In this study, observed temporal temperature distributions in shallow sediment of Lake Taihu (Eastern China) based on three-depth sensors at 14 sites throughout 2016 were used to assess temporal water exchange patterns. Results show that temporal temperature in shallow sediments differed with sampling sites and depths and the temperature amplitudes also clearly shrunk as the offshore distance increasing. Exchange fluxes estimated using the VFLUX 2 model based on temperature amplitude show that alternating-direction temporal flow exists in the eastern zone of Lake Taihu with averages of −13.0, −0.6, and 3.4 mm day−1 (negative represents discharging into the lake) at three nearshore sites (0.5, 2.0, and 6.0 km away from the shoreline, respectively). Whereas downwelling flow occurred throughout almost the entire year with averages of 37.7, 23.5, and 6.6 mm day−1 at the three southern nearshore sites, respectively. However, upwelling flow occurred throughout almost the entire year and varied widely in the western zone with averages of −74.8, 45.9, and −27.0 mm day–1 and in the northern zone with averages of −76.2, −55.3, and −51.1 mm day−1. The estimated fluxes in the central zone were relatively low and varied slightly during the entire year (−15.1 to 22.5 mm day−1 with an average of −0.7 mm day−1). Compared with the sub sensor pair (at 5 and 10 cm), the estimated hyporheic fluxes based on the top sensor pair (at 0 and 5 cm) varied within wider ranges and exhibited relatively larger values. Effects of upwelling flow at the western and northern zones need to be paid attention to on nearshore water quality particularly during winter and spring seasons. Estimated flow patterns at the four zones summarily reflect the seasonal water interaction near the sediment surface of Lake Taihu and are beneficial to improve its comprehensive management. Thermal dispersivity usually used for estimating the thermal diffusivity is more sensitive for upward hyporheic flux estimating even if with a low flux. Temperature amplitude ratio method can be used to estimate the exchange flux and suitable for low flux conditions (either upwelling or downwelling). A better evaluation of the exchange flux near inclined nearshore zones might need an optimized installation of temperature sensors along with the potential flow path and/or a vertical two-dimensional model in the future.
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Schmidt, C., A. Musolff, N. Trauth, M. Vieweg et J. H. Fleckenstein. « Transient analysis of fluctuations of electrical conductivity as tracer in the streambed ». Hydrology and Earth System Sciences Discussions 9, no 5 (23 mai 2012) : 6345–65. http://dx.doi.org/10.5194/hessd-9-6345-2012.
Texte intégralRésumé :
Abstract. Magnitudes and directions of water flux in the streambed are controlled by hydraulic gradients between the groundwater and the stream and by bedform-induced hyporheic exchange flows. These water fluxes vary over time driven by for instance by short term flood events or seasonal variations in stream flow and groundwater level. Variations of electrical conductivity (EC) are used as a natural tracer to detect transient travel times and flow velocities in an in-stream-gravel bar. We present a method to estimate travel times between the stream and measuring locations in the gravel bar by non-linearly matching the EC signals in the time domain. The amount of temporal distortion required to obtain the optimal matching is related to the travel time of the signal. Our analysis revealed that the travel-times increased at higher stream flows because lateral head gradients across the gravel bar are leveled at the time.
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Chou, P. Y., et G. Wyseure. « Lateral inflow into the hyporheic zone tested by a laboratory model ». Hydrology and Earth System Sciences Discussions 5, no 3 (20 juin 2008) : 1567–601. http://dx.doi.org/10.5194/hessd-5-1567-2008.
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Abstract. Groundwater and river water with a different composition interact and exchange in the hyporheic zone. The study of hyporheic zone and its impact on water quality has recently received growing interest because of its role in nutrients and pollutants interactions between rivers and the aquifer. In this research our main purpose is to identify the physical processes and characteristics needed for a numerical model, which include the unsaturated recharge zone, the aquifer and the river bed. In order to investigate such lateral groundwater inflow process, a laboratory J-shaped column experiment was designed. This study determined the transport parameters of the J-shaped column by fitting an analytical solution of the convective-dispersion equation on individual segments to the observed resident breakthrough curves, and by inverse modelling on the entire flow domain for every flux. The obtained transport parameters relation was tested by numerical simulation using HYDRUS 2D/3D. Four steady-state flux conditions (i.e. 0.5 cm hr−1, 1 cm hr−1, 1.5 cm hr−1 and 2 cm hr−1) were applied, transport parameters including pore water velocity and dispersivity were determined for both unsaturated and saturated sections along the column. Results showed that under saturated conditions the dispersivity was fairly constant and independent of the flux. In contrast, dispersivity under unsaturated conditions was flux dependent and increased at lower flux. For our porous medium the dispersion coefficient related best to the quotient of the pore water velocity divided by the water content. A simulation model of the hyporheic exchange of the water and dissolved materials should take this into account.
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Fox, Aryeh, Aaron I. Packman, Fulvio Boano, Colin B. Phillips et Shai Arnon. « Interactions Between Suspended Kaolinite Deposition and Hyporheic Exchange Flux Under Losing and Gaining Flow Conditions ». Geophysical Research Letters 45, no 9 (15 mai 2018) : 4077–85. http://dx.doi.org/10.1029/2018gl077951.
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Wondzell, Steven M., Justin LaNier et Roy Haggerty. « Evaluation of alternative groundwater flow models for simulating hyporheic exchange in a small mountain stream ». Journal of Hydrology 364, no 1-2 (janvier 2009) : 142–51. http://dx.doi.org/10.1016/j.jhydrol.2008.10.011.
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Jackson, T. R., R. Haggerty et S. V. Apte. « A fluid-mechanics based classification scheme for surface transient storage in riverine environments : quantitatively separating surface from hyporheic transient storage ». Hydrology and Earth System Sciences 17, no 7 (15 juillet 2013) : 2747–79. http://dx.doi.org/10.5194/hess-17-2747-2013.
Texte intégralRésumé :
Abstract. Surface transient storage (STS) and hyporheic transient storage (HTS) have functional significance in stream ecology and hydrology. Currently, tracer techniques couple STS and HTS effects on stream nutrient cycling; however, STS resides in localized areas of the surface stream and HTS resides in the hyporheic zone. These contrasting environments result in different storage and exchange mechanisms with the surface stream, which can yield contrasting results when comparing transient storage effects among morphologically diverse streams. We propose a fluid mechanics approach to quantitatively separate STS from HTS that involves classifying and studying different types of STS. As a starting point, a classification scheme is needed. This paper introduces a classification scheme that categorizes different STS in riverine systems based on their flow structure. Eight STS types are identified and some are subcategorized based on characteristic mean flow structure: (1) lateral cavities (emergent and submerged); (2) protruding in-channel flow obstructions (backward- and forward-facing step); (3) isolated in-channel flow obstructions (emergent and submerged); (4) cascades and riffles; (5) aquatic vegetation (emergent and submerged); (6) pools (vertically submerged cavity, closed cavity, and recirculating reservoir); (7) meander bends; and (8) confluence of streams. The long-term goal is to use the classification scheme presented to develop predictive mean residence times for different STS using field-measurable hydromorphic parameters and obtain an effective STS mean residence time. The effective STS mean residence time can then be deconvolved from the transient storage residence time distribution (measured from a tracer test) to obtain an estimate of HTS mean residence time.
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Jackson, T. R., R. Haggerty et S. V. Apte. « A fluid-mechanics-based classification scheme for surface transient storage in riverine environments : quantitatively separating surface from hyporheic transient storage ». Hydrology and Earth System Sciences Discussions 10, no 4 (4 avril 2013) : 4133–206. http://dx.doi.org/10.5194/hessd-10-4133-2013.
Texte intégralRésumé :
Abstract. Surface transient storage (STS) and hyporheic transient storage (HTS) have functional significance in stream ecology and hydrology. Currently, tracer techniques couple STS and HTS effects on stream nutrient cycling; however, STS resides in localized areas of the surface stream and HTS resides in the hyporheic zone. These contrasting environments result in different storage and exchange mechanisms with the surface stream, which can yield contrasting results when comparing transient storage effects among morphologically diverse streams. We propose a fluid mechanics approach to quantitatively separate STS from HTS that involves classifying and studying different types of STS. As a starting point, a classification scheme is needed. This paper introduces a classification scheme that categorizes different STS in riverine systems based on their flow structure. Eight distinct STS types are identified and some are subcategorized based on characteristic mean flow structure: (1) lateral cavities (emerged and submerged); (2) protruding in-channel flow obstructions (backward- and forward-facing step); (3) isolated in-channel flow obstructions (emerged and submerged); (4) cascades and riffles; (5) aquatic vegetation (emerged and submerged); (6) pools (vertically submerged cavity, closed cavity, and recirculating reservoir); (7) meander bends; and (8) confluence of streams. The long-term goal is to use the classification scheme presented to develop predictive mean residence times for different STS using field-measureable hydromorphic parameters and obtain a theoretical STS residence time distribution (RTD). The STS RTD can then be deconvolved from the transient storage RTD (measured from a tracer test) to obtain an estimate of HTS.
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Shelley, Felicity, Megan Klaar, Stefan Krause et Mark Trimmer. « Enhanced hyporheic exchange flow around woody debris does not increase nitrate reduction in a sandy streambed ». Biogeochemistry 136, no 3 (22 novembre 2017) : 353–72. http://dx.doi.org/10.1007/s10533-017-0401-2.
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DATRY, THIBAULT, SCOTT T. LARNED et MIKE R. SCARSBROOK. « Responses of hyporheic invertebrate assemblages to large-scale variation in flow permanence and surface?subsurface exchange ». Freshwater Biology 52, no 8 (août 2007) : 1452–62. http://dx.doi.org/10.1111/j.1365-2427.2007.01775.x.
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Wörman, Anders, Aaron I. Packman, Håkan Johansson et Karin Jonsson. « Effect of flow-induced exchange in hyporheic zones on longitudinal transport of solutes in streams and rivers ». Water Resources Research 38, no 1 (janvier 2002) : 2–1. http://dx.doi.org/10.1029/2001wr000769.
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Cozzetto, Karen D., Kenneth E. Bencala, Michael N. Gooseff et Diane M. McKnight. « The influence of stream thermal regimes and preferential flow paths on hyporheic exchange in a glacial meltwater stream ». Water Resources Research 49, no 9 (septembre 2013) : 5552–69. http://dx.doi.org/10.1002/wrcr.20410.
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