Infiltration Model for Soil Profiles With a Water Table

Chu, S. T.

doi:10.13031/2013.21356

Cited by 7 publications

(3 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…0 for coarse soils and increases with fine soils). Chu (1997) extended the Green-Ampt infiltration model under nonuniform q 0 conditions in areas with a SWT presence. Two cases were described, one with a known q 0 profile and the other with an unknown soil-water profile but known water table level.…”

Section: Shallow Water Table Inluence On Iniltration and Macropore Flmentioning

confidence: 99%

“…SWINGO ) further extends the Green-Ampt infiltration model for initially non-ponded soils under unsteady rainfall conditions with a SWT. SWINGO considers an initial hydrostatic "drained to equilibrium" condition (Bouwer, 1969;Salvucci and Entekhabi, 1995;Chu, 1997), whereby an expression for the soil q as a nonlinear function relating the soil depth and the water table depth can be obtained based on the soil water characteristic curve q = q(h). With the mentioned boundary conditions, the infiltration rate can be described as where the subscripts p and w refer to ponding and column saturation, respectively.…”

Section: Shallow Water Table Inluence On Iniltration and Macropore Flmentioning

confidence: 99%

“…Since the first extended infiltration models included heterogeneities in hydraulic conductivities and water content with depth (Childs and Bybordi, 1969;Bouwer, 1969), MF and infiltration models have advanced to include several important components especially important for holistic RVZ modeling. These are: (i) the differentiation of ponding and non-ponding conditions affecting the degree of activation of MF in the RVZ; (ii) the inclusion of unsteady rainfall conditions, triggering stochasticity on the riparian system dynamics and feedbacks from surface runoff to the SWT; and (iii) the consideration of the common seasonal water table boundary often found in RVZs (Salvucci and Entekhabi, 1995;Chu, 1997;Muñoz-Carpena et al, 2018), altering the dynamics of the infiltration process and the soil moisture profile in a riparian zone.…”

Section: Comparison Of Macropore Flow Modelsmentioning

confidence: 99%

See 2 more Smart Citations

Riparian Vadose Zone Preferential Flow: Review of Concepts, Limitations, and Perspectives

Orozco-López

Muñoz‐Carpena

Gao

et al. 2018

Vadose Zone Journal

View full text Add to dashboard Cite

The design and analysis of surface water pollution control practices such as vegetative filter strips and riparian buffers typically focus on surface runoff, with limited attention given to subsurface flow and transport. Field evidence suggests a prevalence of macropore flow (MF) in the riparian vadose zone (RVZ) due to abundant biological activity (e.g., fauna and roots) and steep hydraulic gradients created by the adjacent stream and the presence of a seasonally shallow water table (SWT). Because rapid leaching and subsurface transport of contaminants can be significant with MF, their prevalence in riparian buffers can negate the intended benefits of this widely adopted surface runoff pollution control practice. While theories exist for modeling preferential flow processes, experimental and modeling techniques are still lacking to characterize in situ RVZ macropore network morphologies at the soil profile and landscape scales. Importantly, the presence of a seasonal SWT can increase MF and transport processes neglected in current analyses. Additional research is needed to evaluate holistic modeling frameworks that can represent MF from measurable parameters at the riparian field scale. In this work, we review various MF theories and concepts suitable to RVZ conditions and identify current limitations and knowledge gaps. We emphasize the use of dual-permeability approaches as a compromise between model complexity and parameter identifiability. We also identify the need for wellcontrolled experimental studies using the latest monitoring technology and validation studies at the laboratory and field scales. Only then can decision-support tools realistically predict the influence of preferential flow processes on the performance of riparian buffers as a surface water quality control practice.Abbreviations: MF, macropore flow; RVZ, riparian vadose zone; SR, source-responsive; SWT, shallow water table.Floodplains are important ecosystems influenced significantly by adjacent agricultural and urban land-use practices. Soil disturbance and agrochemicals applied to upland areas can lead to a release of contaminants, such as sediments, nutrients (N and P), and pesticides that degrade adjacent surface waters, reduce an ecosystem's resilience, and eventually result in a potentially irreversible regime shift of the aquatic environment with unpredictable consequences (Folke et al., 2004).Within floodplains, riparian zones are variable-width areas of natural or implanted vegetation (i.e., riparian buffers) bordering streams or channels. Because of their dense vegetation and high biological activity, riparian areas serve as a buffer and transition zone between the rest of the floodplain and the surface water body. Best management practices are often used to control water pollution, including the use of these riparian areas, by selecting vegetation and characteristics that reduce overall flow and transport. Thus, riparian buffers are often designed and managed as a best management practice to control surface runoff pollution (Low...

show abstract

Section: Shallow Water Table Inluence On Iniltration and Macropore Flmentioning

confidence: 99%

Section: Shallow Water Table Inluence On Iniltration and Macropore Flmentioning

confidence: 99%

Section: Comparison Of Macropore Flow Modelsmentioning

confidence: 99%

See 1 more Smart Citation

Riparian Vadose Zone Preferential Flow: Review of Concepts, Limitations, and Perspectives

Orozco-López

Muñoz‐Carpena

Gao

et al. 2018

Vadose Zone Journal

View full text Add to dashboard Cite

show abstract

Appropriate vertical discretization of Richards' equation for two‐dimensional watershed‐scale modelling

Downer

Ogden

2003

Hydrological Processes

View full text Add to dashboard Cite

Abstract:A number of watershed-scale hydrological models include Richards' equation (RE) solutions, but the literature is sparse on information as to the appropriate application of RE at the watershed scale. In most published applications of RE in distributed watershed-scale hydrological modelling, coarse vertical resolutions are used to decrease the computational burden. Compared to point-or field-scale studies, application at the watershed scale is complicated by diverse runoff production mechanisms, groundwater effects on runoff production, runon phenomena and heterogeneous watershed characteristics. An essential element of the numerical solution of RE is that the solution converges as the spatial resolution increases. Spatial convergence studies can be used to identify the proper resolution that accurately describes the solution with maximum computational efficiency, when using physically realistic parameter values. In this study, spatial convergence studies are conducted using the two-dimensional, distributed-parameter, gridded surface subsurface hydrological analysis (GSSHA) model, which solves RE to simulate vadose zone fluxes. Tests to determine if the required discretization is strongly a function of dominant runoff production mechanism are conducted using data from two very different watersheds, the Hortonian Goodwin Creek Experimental Watershed and the non-Hortonian Muddy Brook watershed. Total infiltration, stream flow and evapotranspiration for the entire simulation period are used to compute comparison statistics. The influences of upper and lower boundary conditions on the solution accuracy are also explored. Results indicate that to simulate hydrological fluxes accurately at both watersheds small vertical cell sizes, of the order of 1 cm, are required near the soil surface, but not throughout the soil column. The appropriate choice of approximations for calculating the near soil-surface unsaturated hydraulic conductivity can yield modest increases in the required cell size. Results for both watersheds are quite similar, even though the soils and runoff production mechanisms differ greatly between the two catchments.

show abstract

Comment on “Modeling slope rainfall-infiltration-runoff process with shallow water table during complex rainfall patterns” by Wu et al. (2021)

Muñoz‐Carpena

Lauvernet

Carluer

et al. 2021

Journal of Hydrology X

View full text Add to dashboard Cite

Infiltration Model for Soil Profiles With a Water Table

Cited by 7 publications

References 0 publications

Riparian Vadose Zone Preferential Flow: Review of Concepts, Limitations, and Perspectives

Riparian Vadose Zone Preferential Flow: Review of Concepts, Limitations, and Perspectives

Appropriate vertical discretization of Richards' equation for two‐dimensional watershed‐scale modelling

Comment on “Modeling slope rainfall-infiltration-runoff process with shallow water table during complex rainfall patterns” by Wu et al. (2021)

Contact Info

Product

Resources

About