A modified Green–Ampt model for water infiltration and preferential flow

Preferential flow is significant for its contribution to rapid response to hydrologic inputs at the soil surface and unsaturated zone flow, which is critical for flow generation in rainfall–runoff (RR) models. In combination with the diffuse and source-responsive flow equations, a new model for water infiltration that incorporates preferential flow is proposed in this paper. Its performance in estimating soil moisture at the catchment scale was tested with observed water content data from the Elder sub-basin of the South Fork Eel River, located in northern California, USA. The case study shows that the new model can improve the accuracy of soil water content simulation even at the catchment scale. The impacts of preferential flow on RR simulation were tested by the Modello Idrologico Semi-Distributio in continuo lumped hydrological model for the Elder River basin. Eleven significant floods events, which were defined as having flood peak magnitudes greater than ten times average discharge during the study period, were employed to assess runoff simulation improvement. The accuracy of the runoff simulation incorporating the preferential flow at the catchment scale improved significantly according to the likelihood ratio test.

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Water repellency of clay, sand and organic soils in Finland

Agricultural and Food Science ◽

10.2137/145960607783328218 ◽

2008 ◽

Vol 16 (3) ◽

pp. 267 ◽

Cited By ~ 4

Author(s):

K. RASA ◽

R. HORN ◽

M. RÄTY

Keyword(s):

Preferential Flow ◽

Management Practice ◽

Soil Surface ◽

Water Repellency ◽

Organic Soil ◽

Water Infiltration ◽

Organic Soils ◽

Water Repellent ◽

Moisture Regime ◽

Wetting Process

Water repellency (WR) delays soil wetting process, increases preferential flow and may give rise to surface runoff and consequent erosion. WR is commonly recognized in the soils of warm and temperate climates. To explore the occurrence of WR in soils in Finland, soil R index was studied on 12 sites of different soil types. The effects of soil management practice, vegetation age, soil moisture and drying temperature on WR were studied by a mini-infiltrometer with samples from depths of 0-5 and 5-10 cm. All studied sites exhibited WR (R index >1.95) at the time of sampling. WR increased as follows: sand (R = 1.8-5.0) < clay (R = 2.4-10.3) < organic (R = 7.9-undefined). At clay and sand, WR was generally higher at the soil surface and at the older sites (14 yr.), where organic matter is accumulated. Below 41 vol. % water content these mineral soils were water repellent whereas organic soil exhibited WR even at saturation. These results show that soil WR also reduces water infiltration at the prevalent field moisture regime in the soils of boreal climate. The ageing of vegetation increases WR and on the other hand, cultivation reduces or hinders the development of WR.;

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Liquid water infiltration into a layered snowpack: evaluation of a 3D water transport model with laboratory experiments

10.5194/hess-2017-200 ◽

2017 ◽

Author(s):

Hiroyuki Hirashima ◽

Francesco Avanzi ◽

Satoru Yamaguchi

Keyword(s):

Water Content ◽

Liquid Water ◽

Laboratory Experiments ◽

Preferential Flow ◽

Transport Model ◽

Water Infiltration ◽

Flow Paths ◽

Preferential Flow Paths ◽

Capillary Barriers ◽

Wet Snow

Abstract. The heterogeneous movement of liquid water through snowpack during precipitation and snowmelt leads to complex liquid water distributions that are important for avalanche and runoff forecasting. We reproduced the formation of capillary barriers and the development of preferential flow through snow using a multi-dimensional water transport model, which was then validated using laboratory experiments of liquid water infiltration into layered, initially dry snow. Three-dimensional simulations assumed the same column shape and size, grain size, snow density, and water input rate as the laboratory experiments. Model evaluation focused on the timing of water movement, the thickness of the upper layer affected by ponding, and on water content profiles and the wet snow fraction. Simulation results showed that the model reconstructs some relevant features of capillary barriers including ponding in the upper layer, preferential infiltration far from the interface, and the timing of liquid water arrival at the snow base. In contrast, the area of preferential flow paths was usually underestimated and consequently the averaged water content in areas characterized by preferential flow paths was also underestimated. Improving the representation of water preferential infiltration into initially dry snow is necessary to reproduce the transition from a dry-snow-dominant condition to a wet-snow-dominant one, especially in long-period simulations.

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Modelling uniform and preferential flow in bioretention systems

10.5194/egusphere-egu21-10576 ◽

2021 ◽

Author(s):

Asra Asry ◽

Jérémie Bonneau ◽

Gersende Fernandes ◽

Gislain Lipeme Kouyi ◽

Bernard Chocat ◽

...

Keyword(s):

Field Data ◽

Preferential Flow ◽

Water Cycle ◽

Mass Conservation ◽

Water Infiltration ◽

Catchment Scale ◽

Rainfall Events ◽

Proposed Model ◽

Infiltration Tests ◽

Urban Stormwater Runoff

Bioretention systems are increasingly used worldwide to mitigate the impacts of urban stormwater runoff on the water cycle. The proper management of bioretention systems requires accurate modeling of physical processes occurring within these systems. This study developed and tested a generic and physically-based model called Infiltron-mod. This model makes use of the Darcian approach (assuming Mualem-van Genuchten model for the description of the soil hydraulic properties) and mass conservation. The first version of the model considers evapotranspiration, overflow, exfiltration to surrounding soils, along with the filter hydraulic head and underdrain discharge. The proposed model was tested against field data from a monitored bioretention basin in Melbourne, Australia. We used two rainfall events to calibrate the model and 20 rainfall events for its validation. We achieved quite nice fits of experimental data with median NSE values in the order of 0.7-0.75 for the outflow rates. Despite good performance for outflow rates, we noticed the potential for improvement for the simulation of the height of water in the systems. Such discrepancy is probably the result of preferential flows.As a second step, we developed a specific module to implement the dual permeability approach to model preferential flow. Such an approach may simulate the concomitancy of matrix flow in part of the system and rapid preferential infiltration into macropores. The new module Infiltron-mod-pref was implemented and investigated. Prior to its use for field data, we validated the new module against more straightforward water infiltration experiments. Several large ring infiltration tests were performed on a field dedicated to infiltrating stormwater, and the two versions of the proposed model, Infiltron-mod and Infiltron-mod-Pref. We clearly showed the benefit to account for the preferential flow in the model. The next step will be the use of Infiltron-mod_Pref for field data from the monitored bioretention basin in Melbourne.The proposed approach then seems a useful first step to assess both performance and impact of bioretention basins for catchment-scale flow regime management and has real potential for application where user-friendly and simple model calibration and deployment are desired.

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INFILTRON package for assessing infiltration & filtration functions of urban soils

10.5194/egusphere-egu2020-11269 ◽

2020 ◽

Author(s):

Laurent Lassabatere ◽

Anne-Cécile De Giacomoni ◽

Rafael Angulo-Jaramillo ◽

Gislain Lipeme Kouyi ◽

Matteo Martini ◽

...

Keyword(s):

Urban Areas ◽

Urban Soils ◽

Preferential Flow ◽

Water Cycle ◽

Water Infiltration ◽

Soil Physics ◽

Catchment Scale ◽

Specific Device ◽

Ground Penetrating

The extension of urban and peri-urban areas and the related artificialization of soils drastically impacts the water cycle as well as biogeochemical cycles. In particular, the sealing of soils with impervious surfaces such as roads increases runoff and decreases concomitant infiltration. At the catchment scale, more significant amounts of stormwater must be collected and managed to prevent from flooding urban areas and mitigate discharge to the environment. Sustainable Urban Drainage Systems (SUDS) were developed to alleviate these problems. These systems allow the restoration of one of the main functions of urban and peri-urban soils, i.e., infiltrating stormwater. They simultaneously reduce the risk of flooding and increase groundwater recharge. Another essential service must be ensured and optimized: the removal of pollutants from infiltrating water by the soil, to avoid the degradation of the quality of the groundwater.The INFILTRON project aims to design a methodology for the assessment of infiltration and filtration of pollutants by SUDS. The project is a collaboration of many partners, with expertise in soil physics, urban hydrology, nanoparticle engineering, and modeling, to engineer a specific device for the simultaneous monitoring of water infiltration and pollutant filtration. This infiltration device both infiltrates water and injects nanoparticles (NPs) into the soil. It was sized to account for preferential flow, which is known to have a significant impact on infiltration and pollutant transfer. The engineered NPs were designed to be detectable in the ground using ground-penetrating radar (GPR) and to mimic the transfer of nano-pollutants (emerging pollutants, bacteria, etc.) commonly found in real stormwater. An infiltration-filtration model was developed to interpret the experimental data and to quantify two indicators for the assessment of water infiltration and pollutant filtration. INFILTRON will provide a very interesting toolbox for practitioners and stakeholders for the evaluation of the infiltration and filtration functions of not only SUDS within the framework of stormwater management, but also anthropized soils within the management of urban and peri-urban areas.

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Using dye tracer for visualizing roots impact on soil structure and soil porous system

Biologia ◽

10.1515/biolog-2015-0166 ◽

2015 ◽

Vol 70 (11) ◽

Cited By ~ 5

Author(s):

Radka Kodešová ◽

Karel Němeček ◽

Anna Žigová ◽

Antonín Nikodem ◽

Miroslav Fér

Keyword(s):

Water Uptake ◽

Soil Structure ◽

Preferential Flow ◽

Soil Surface ◽

Water Infiltration ◽

Porous System ◽

Field Scale ◽

Thin Sections ◽

Dye Tracer ◽

The Impact

AbstractPlants influence the water regime in soil by both water uptake and an uneven distribution of water infiltration at the soil surface. The latter process is more poorly studied, but it is well known that roots modify soil structure by enhancing aggregation and biopore production. This study used a dye tracer to visualize the impact of plants on water flow in the topsoil of a Greyic Phaeozem. Brilliant blue was ponded to 10 cm height in a 1 m × 1 m frame in the field immediately after harvest of winter wheat (Triticum aestivum L.). After complete infiltration, the staining patterns within the vertical and horizontal field-scale sections were studied. In addition, soil thin sections were made and micromorphological images were used to study soil structure and dye distribution at the microscale. The field-scale sections clearly documented uneven dye penetration into the soil surface, which was influenced by plant presence and in some cases by mechanical compaction of the soil surface. The micromorphological images showed that root activities compress soil and increases the bulk density near the roots (which could be also result of root water uptake and consequent soil adhesion). On the other hand in few cases a preferential flow along the roots was observed.

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Coupling large and small ring infiltration experiments for investigating preferential flow

10.5194/egusphere-egu21-7355 ◽

2021 ◽

Author(s):

Laurent Lassabatere ◽

Simone Di Prima ◽

Paola Concialdi ◽

Majdi Abou Najm ◽

Ryan D. Stewart ◽

...

Keyword(s):

Preferential Flow ◽

Soil Surface ◽

Water Infiltration ◽

Small Ring ◽

Hydraulic Parameters ◽

Ring Size ◽

Large Rings ◽

Cumulative Infiltration ◽

The Impact ◽

Lithological Heterogeneity

Preferential flow is more the rule than the exception. Water infiltration is often led by preferential flow due to macropores, specific soil structures (e.g., aggregates, macropore networks), or lithological heterogeneity (occurrence of materials with contrasting hydraulic properties). Water infiltration in soils prone to preferential flow strongly depends on soil features below the soil surface, but also the initiation of water infiltration at the surface. When the macropore networks are not dense, with only a few macropores intercepting the soil surface, water infiltration experiments with ring size in the order of 10-15 cm diameter may overlook sampling macropore networks during some infiltration runs, minimizing the effect of macropore flow on the bulk water infiltration at the plot scale.In this study, we investigated the effect of ring size on water infiltration into soils prone to preferential flow. We used two ring sizes: small (15 cm in diameter) and large (50 cm in diameter). By doing so, we hypothesized that the large rings, sampling a more representative soil volume, will maximize the probability to intercept and activate a macropore network. In contrast, the small rings may activate the macropore network only occasionally, with other infiltration runs mainly sampling the soil matrix. Thus, the small rings are expected to provide more variable results. On the other hand, the large rings are expected to provide more homogeneous results in line with the soil's bulk infiltration capability, including all pore networks at the plot scale.Three different sites were sampled with varying types of preferential flow (macropore-induced versus lithological heterogeneity induced). The experimental plan included inserting large rings at several places in the experimental sites with a dozen small rings nearby to sample the same soil. All the rings were submitted to a similar positive constant water pressure head at the soil surface. The cumulative infiltrations were then monitored and treated with BEST algorithms to get the efficient hydraulic parameters. Note that the cumulative infiltration could not be compared directly since lateral water fluxes varied in extent and geometry between the different ring sizes. The impacts of the ring size on the magnitude of cumulative infiltration and related estimated hydraulic parameters were discussed. Our results demonstrated the impact of ring size but also the dependency of such effect on the site and the type of flow.Our results contribute to understanding preferential flow in heterogeneous soils and the complexity of its measure using regular water infiltration devices and protocols.

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Effects of hillslope position on soil water infiltration and preferential flow in tropical forest in southwest China

Journal of Environmental Management ◽

10.1016/j.jenvman.2021.113672 ◽

2021 ◽

Vol 299 ◽

pp. 113672

Author(s):

Chunfeng Chen ◽

Xin Zou ◽

Ashutosh Kumar Singh ◽

Xiai Zhu ◽

Wanjun Zhang ◽

...

Keyword(s):

Tropical Forest ◽

Soil Water ◽

Preferential Flow ◽

Southwest China ◽

Water Infiltration ◽

Soil Water Infiltration

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Effects of textural layering on water regimes in sandy soils in a desert-oasis ecotone, Northwestern China

10.5194/egusphere-egu21-9324 ◽

2021 ◽

Author(s):

Chengpeng Sun ◽

Wenzhi Zhao ◽

Hu Liu ◽

Yongyong Zhang ◽

Hong Zhou

Keyword(s):

Water Content ◽

Soil Water ◽

Soil Water Content ◽

Water Infiltration ◽

Northwestern China ◽

Soil Profiles ◽

Burial Depth ◽

Layered Soils ◽

Water Regimes ◽

Desert Oasis

Textural layering of soil plays an important role in distributing and regulating resources for plants in many semiarid and arid landscapes. However, the spatial patterns of textural layering and the potential effects on soil hydrology and water regimes are poorly understood, especially in arid sandy soil environments like the desert-oasis ecotones in northwestern China. This work aims to determine the distribution of textural layered soils, analyze the effects of different soil-textural configurations on water regimes, and evaluate which factors affect soil water infiltration and retention characteristics in such a desert-oasis ecotone. We measured soil water content and mineral composition in 87 soil profiles distributed along 3 transects in the study area. Constant-head infiltration experiments were conducted at 9 of the soil profiles with different texture configurations. The results showed that textural layered soils were patchily but extensively distributed throughout the study area (with a combined surface area percentage of about 84%). Soil water content in the profiles ranged from 0.002 to 0.27 g/cm3 during the investigation period, and significantly and positively correlated with the thickness of a medium-textured (silt or silt loam) layer (P < 0.001). The occurrence of a medium-textured layer increased field capacity (FC) and wilting point (WP), and decreased available water-holding capacity in soil profiles. Burial depth of the medium-textured layer had no clear effects on water retention properties, but the layer thickness tended to. In textural layered soils, smaller water infiltration rate and cumulative infiltration, and shallower depths of wetting fronts were detected, compared with homogeneous sand profiles. The thickness and burial depth of medium-textured layers had obvious effects on infiltration, but the magnitude of the effects depended on soil texture configuration. The revealed patterns of soil textural layering and the potential effects on water regimes may provide new insight into the sustainable management of rainfed vegetation in the desert-oasis ecotones of arid northwestern China and other regions with similar environments around the world.

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Form and function in hillslope hydrology: characterization of subsurface flow based on response observations

Hydrology and Earth System Sciences ◽

10.5194/hess-21-3727-2017 ◽

2017 ◽

Vol 21 (7) ◽

pp. 3727-3748 ◽

Cited By ~ 26

Author(s):

Lisa Angermann ◽

Conrad Jackisch ◽

Niklas Allroggen ◽

Matthias Sprenger ◽

Erwin Zehe ◽

...

Keyword(s):

Preferential Flow ◽

Explanatory Power ◽

Subsurface Flow ◽

Time Lapse ◽

Storm Event ◽

Monitoring Methods ◽

Catchment Scale ◽

Flow Paths ◽

Form And Function ◽

And Function

Abstract. The phrase form and function was established in architecture and biology and refers to the idea that form and functionality are closely correlated, influence each other, and co-evolve. We suggest transferring this idea to hydrological systems to separate and analyze their two main characteristics: their form, which is equivalent to the spatial structure and static properties, and their function, equivalent to internal responses and hydrological behavior. While this approach is not particularly new to hydrological field research, we want to employ this concept to explicitly pursue the question of what information is most advantageous to understand a hydrological system. We applied this concept to subsurface flow within a hillslope, with a methodological focus on function: we conducted observations during a natural storm event and followed this with a hillslope-scale irrigation experiment. The results are used to infer hydrological processes of the monitored system. Based on these findings, the explanatory power and conclusiveness of the data are discussed. The measurements included basic hydrological monitoring methods, like piezometers, soil moisture, and discharge measurements. These were accompanied by isotope sampling and a novel application of 2-D time-lapse GPR (ground-penetrating radar). The main finding regarding the processes in the hillslope was that preferential flow paths were established quickly, despite unsaturated conditions. These flow paths also caused a detectable signal in the catchment response following a natural rainfall event, showing that these processes are relevant also at the catchment scale. Thus, we conclude that response observations (dynamics and patterns, i.e., indicators of function) were well suited to describing processes at the observational scale. Especially the use of 2-D time-lapse GPR measurements, providing detailed subsurface response patterns, as well as the combination of stream-centered and hillslope-centered approaches, allowed us to link processes and put them in a larger context. Transfer to other scales beyond observational scale and generalizations, however, rely on the knowledge of structures (form) and remain speculative. The complementary approach with a methodological focus on form (i.e., structure exploration) is presented and discussed in the companion paper by Jackisch et al.(2017).

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