The Role of Horton Overland Flow in Rainfall-runoff Process in an Unchanneled Catchment Covered by Unmanaged Hinoki Plantation

This research was carried out to quantify the role of vegetative cover in reducing runoff and erosion from rehabilitated mined land. Duplicate plots 1.5 m wide and 12 m long were prepared on a rehabilitated area of the Meandu Mine, Tarong, with vegetative cover of 0, 23%, 37%, 47%, and 100%. The area had a uniform 15% slope, and there were no rill or gully lines present. Simulated rain equivalent to a 1 : 100 year storm was applied to the plots, and runoff and erosion were measured. Infiltration totals and rates increased strongly with increasing vegetative cover. There was visibly greater infiltration under vegetation. Erosion from the simulated storm was greatly reduced by vegetative cover, declining from 30–35 t/ha at 0% vegetative cover to 0.5 t/ha at 47% cover. Reductions in erosion at lower levels of vegetative cover were greater than predicted by the cover/erosion relationship used in the USLE. The dominantly stoloniferous growth habit of the grass at this site may have increased the effectiveness of vegetative cover in this study. To allow the data to be extrapolated to slopes longer than 12 m, a series of overland flows were applied to the upslope boundaries of the plots, simulating flows on slopes up to 70 m long. Detachment and transport of sediment by applied overland flow was similarly reduced by vegetative cover, and results from the overland flow study also indicate that for slopes up to 70 m long with grass cover of 47% or greater, erosion rates will be minimal, even under extreme rainfall/runoff events.

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The dominant runoff processes on grassland versus bare soil hillslopes in a temperate environment - An experimental study

Journal of Hydrology and Hydromechanics ◽

10.2478/johh-2019-0018 ◽

2019 ◽

Vol 67 (4) ◽

pp. 297-304 ◽

Cited By ~ 4

Author(s):

Gabriel Minea ◽

Gabriela Ioana-Toroimac ◽

Gabriela Moroşanu

Keyword(s):

Overland Flow ◽

Bare Soil ◽

Rainfall Runoff ◽

Runoff Generation ◽

Rainfall Events ◽

Natural Rainfall ◽

Antecedent Precipitation ◽

Temperate Environment ◽

The Relationship

Abstract This paper aimed to investigate the dominant runoff processes (DRP’s) at plot-scale in the Curvature Subcarpathians under natural rainfall conditions characteristic for Romania’s temperate environment. The study was based on 32 selected rainfall-runoff events produced during the interval April–September (2014–2017). By comparing water balance on the analyzed Luvisol plots for two types of land use (grassland vs. bare soil), we showed that DRP’s are mostly formed by Hortonian Overland Flow (HOF), 47% vs. 59% respectively. On grassland, HOF is followed by Deep Percolation (DP, 31%) and Fast Subsurface Flow (SSF, 22%), whereas, on bare soil, DP shows a higher percentage (38%) and SSF a lower one (3%), which suggests that the soil-root interface controls the runoff generation. Concerning the relationship between antecedent precipitation and runoff, the study indicated the nonlinearity of the two processes, more obvious on grassland and in drought conditions than on bare soil and in wet conditions (as demonstrated by the higher runoff coefficients). Moreover, the HOF appeared to respond differently to rainfall events on the two plots - slightly longer lag-time, lower discharge and lower volume on grassland - which suggests the hydrologic key role of vegetation in runoff generation processes.

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Multi-Objective Model-Based Assessment of Green-Grey Infrastructures for Urban Flood Mitigation

Hydrology ◽

10.3390/hydrology8030110 ◽

2021 ◽

Vol 8 (3) ◽

pp. 110

Author(s):

Carlos Martínez ◽

Zoran Vojinovic ◽

Arlex Sanchez

Keyword(s):

Green Infrastructure ◽

Overland Flow ◽

Flood Damage ◽

Optimal Number ◽

Rainfall Runoff ◽

Urban Catchment ◽

Model Based ◽

Model Domain ◽

Infiltration Processes ◽

2D Model

This paper presents the performance quantification of different green-grey infrastructures, including rainfall-runoff and infiltration processes, on the overland flow and its connection with a sewer system. The present study suggests three main components to form the structure of the proposed model-based assessment. The first two components provide the optimal number of green infrastructure (GI) practices allocated in an urban catchment and optimal grey infrastructures, such as pipe and storage tank sizing. The third component evaluates selected combined green-grey infrastructures based on rainfall-runoff and infiltration computation in a 2D model domain. This framework was applied in an urban catchment in Dhaka City (Bangladesh) where different green-grey infrastructures were evaluated in relation to flood damage and investment costs. These practices implemented separately have an impact on the reduction of damage and investment costs. However, their combination has been shown to be the best action to follow. Finally, it was proved that including rainfall-runoff and infiltration processes, along with the representation of GI within a 2D model domain, enhances the analysis of the optimal combination of infrastructures, which in turn allows the drainage system to be assessed holistically.

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Hillslope Contribution to the Clark Instantaneous Unit Hydrograph: Application to the Seolmacheon Basin, Korea

Water ◽

10.3390/w13121707 ◽

2021 ◽

Vol 13 (12) ◽

pp. 1707

Author(s):

Chulsang Yoo ◽

Huy Phuong Doan ◽

Changhyun Jun ◽

Wooyoung Na

Keyword(s):

Peak Flow ◽

Peak Time ◽

Rainfall Runoff ◽

Maximum Rainfall ◽

Rainfall Events ◽

Storage Coefficient ◽

Channel Velocity ◽

Linear Reservoir ◽

Mountainous Basin

In this study, the time–area curve of an ellipse is analytically derived by considering flow velocities within both channel and hillslope. The Clark IUH is also derived analytically by solving the continuity equation with the input of the derived time–area curve to the linear reservoir. The derived Clark IUH is then evaluated by application to the Seolmacheon basin, a small mountainous basin in Korea. The findings in this study are summarized as follows. (1) The time–area curve of a basin can more realistically be derived by considering both the channel and hillslope velocities. The role of the hillslope velocity can also be easily confirmed by analyzing the derived time–area curve. (2) The analytically derived Clark IUH shows the relative roles of the hillslope velocity and the storage coefficient. Under the condition that the channel velocity remains unchanged, the hillslope velocity controls the runoff peak flow and the concentration time. On the other hand, the effect of the storage coefficient can be found in the runoff peak flow and peak time, as well as in the falling limb of the runoff hydrograph. These findings are also confirmed in the analysis of rainfall–runoff events of the Seolmacheon basin. (3) The effect of the hillslope velocity varies considerably depending on the rainfall events, which is also found to be mostly dependent upon the maximum rainfall intensity.

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Role of Runoff–Infiltration Partitioning and Resolved Overland Flow on Land–Atmosphere Feedbacks: A Case Study with the WRF-Hydro Coupled Modeling System for West Africa

Journal of Hydrometeorology ◽

10.1175/jhm-d-15-0089.1 ◽

2016 ◽

Vol 17 (5) ◽

pp. 1489-1516 ◽

Cited By ~ 39

Author(s):

Joel Arnault ◽

Sven Wagner ◽

Thomas Rummler ◽

Benjamin Fersch ◽

Jan Bliefernicht ◽

...

Keyword(s):

West Africa ◽

Overland Flow ◽

River Flow ◽

Efficiency Coefficient ◽

Wet Season ◽

Coupled Modeling ◽

Study Region ◽

Outer Domain ◽

Terrestrial Water

Abstract The analysis of land–atmosphere feedbacks requires detailed representation of land processes in atmospheric models. The focus here is on runoff–infiltration partitioning and resolved overland flow. In the standard version of WRF, runoff–infiltration partitioning is described as a purely vertical process. In WRF-Hydro, runoff is enhanced with lateral water flows. The study region is the Sissili catchment (12 800 km2) in West Africa, and the study period is from March 2003 to February 2004. The WRF setup here includes an outer and inner domain at 10- and 2-km resolution covering the West Africa and Sissili regions, respectively. In this WRF-Hydro setup, the inner domain is coupled with a subgrid at 500-m resolution to compute overland and river flow. Model results are compared with TRMM precipitation, model tree ensemble (MTE) evapotranspiration, Climate Change Initiative (CCI) soil moisture, CRU temperature, and streamflow observation. The role of runoff–infiltration partitioning and resolved overland flow on land–atmosphere feedbacks is addressed with a sensitivity analysis of WRF results to the runoff–infiltration partitioning parameter and a comparison between WRF and WRF-Hydro results, respectively. In the outer domain, precipitation is sensitive to runoff–infiltration partitioning at the scale of the Sissili area (~100 × 100 km2), but not of area A (500 × 2500 km2). In the inner domain, where precipitation patterns are mainly prescribed by lateral boundary conditions, sensitivity is small, but additionally resolved overland flow here clearly increases infiltration and evapotranspiration at the beginning of the wet season when soils are still dry. The WRF-Hydro setup presented here shows potential for joint atmospheric and terrestrial water balance studies and reproduces observed daily discharge with a Nash–Sutcliffe model efficiency coefficient of 0.43.

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Rainfall runoff in soil erosion with simulated rainfall, overland flow and cover

Soil Research ◽

10.1071/sr9830109 ◽

1983 ◽

Vol 21 (2) ◽

pp. 109 ◽

Cited By ~ 25

Author(s):

MJ Singer ◽

PH Walker

Keyword(s):

Soil Erosion ◽

Soil Loss ◽

Rainfall Intensity ◽

Overland Flow ◽

Podzolic Soil ◽

Simulated Rainfall ◽

Rainfall Runoff ◽

Runoff Water ◽

Soil Transport ◽

Raindrop Impact

The 20-100 mm portion of a yellow podzolic soil (Albaqualf) from the Ginninderra Experiment Station (A.C.T.) was used in a rainfall simulator and flume facility to elucidate the interactions between raindrop impact, overland water flow and straw cover as they affect soil erosion. A replicated factorial design compared soil loss in splash and runoff from 50 and 100 mm h-1 rainfall, the equivalent of 100 mm h-1 overland flow, and 50 and 100 mm h-1 rainfall plus the equivalent of 100 mm h-' overland flow, all at 0, 40 and 80% straw cover on a 9% slope. As rainfall intensity increased, soil loss in splash and runoff increased. Within cover levels, the effect of added overland flow was to decrease splash but to increase total soil loss. This is due to an interaction between raindrops and runoff which produces a powerful detaching and transporting mechanism within the flow known as rain-flow transportation. Airsplash is reduced, in part, because of the changes in splash characteristics which accompany changes in depths of runoff water. Rain-flow transportation accounted for at least 64% of soil transport in the experiment and airsplash accounted for no more than 25% of soil transport The effects of rainfall, overland flow and cover treatments, rather than being additive, were found to correlate with a natural log transform of the soil loss data.

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Rainfall-runoff modelling in a catchment with a complex groundwater flow system: application of the Representative Elementary Watershed (REW) approach

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-2-639-2005 ◽

2005 ◽

Vol 2 (3) ◽

pp. 639-690 ◽

Cited By ~ 1

Author(s):

G. P. Zhang ◽

H. H. G. Savenije

Keyword(s):

River Basin ◽

Overland Flow ◽

Model Performance ◽

Source Area ◽

Subsurface Water ◽

Watershed Hydrology ◽

Rainfall Runoff ◽

Data Set ◽

Physically Based ◽

Infiltration Excess

Abstract. Based on the Representative Elementary Watershed (REW) approach, the modelling tool REWASH (Representative Elementary WAterShed Hydrology) has been developed and applied to the Geer river basin. REWASH is deterministic, semi-distributed, physically based and can be directly applied to the watershed scale. In applying REWASH, the river basin is divided into a number of sub-watersheds, so called REWs, according to the Strahler order of the river network. REWASH describes the dominant hydrological processes, i.e. subsurface flow in the unsaturated and saturated domains, and overland flow by the saturation-excess and infiltration-excess mechanisms. Through flux exchanges among the different spatial domains of the REW, surface and subsurface water interactions are fully coupled. REWASH is a parsimonious tool for modelling watershed hydrological response. However, it can be modified to include more components to simulate specific processes when applied to a specific river basin where such processes are observed or considered to be dominant. In this study, we have added a new component to simulate interception using a simple parametric approach. Interception plays an important role in the water balance of a watershed although it is often disregarded. In addition, a refinement for the transpiration in the unsaturated zone has been made. Finally, an improved approach for simulating saturation overland flow by relating the variable source area to both the topography and the groundwater level is presented. The model has been calibrated and verified using a 4-year data set, which has been split into two for calibration and validation. The model performance has been assessed by multi-criteria evaluation. This work is the first full application of the REW approach to watershed rainfall-runoff modelling in a real watershed. The results demonstrate that the REW approach provides an alternative blueprint for physically based hydrological modelling.

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The role of catchment classification in rainfall-runoff modeling

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-8-6113-2011 ◽

2011 ◽

Vol 8 (3) ◽

pp. 6113-6153 ◽

Cited By ~ 2

Author(s):

Y. He ◽

A. Bárdossy ◽

E. Zehe

Keyword(s):

Classification Scheme ◽

Intrinsic Value ◽

Climatic Conditions ◽

Ungauged Basins ◽

Classification Methods ◽

Rainfall Runoff ◽

Catchment Hydrology ◽

Natural Classification ◽

Runoff Modeling

Abstract. A sound catchment classification scheme is a fundamental step towards improved catchment hydrology science and prediction in ungauged basins. Two categories of catchment classification methods are presented in the paper. The first one is based directly on physiographic properties and climatic conditions over a catchment and regarded as a Linnaean type or natural classification scheme. The second one is based on numerical clustering and regionalization methods and considered as a statistical or arbitrary classification scheme. This paper reviews each category including what has been done since recognition of the intrinsic value of catchment classification, what is being done in the current research, as well as what is to be done in the future.

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A hysteretic model for rainfall-runoff of a simplifed catchment

10.5194/egusphere-egu21-16172 ◽

2021 ◽

Author(s):

Denis Flynn ◽

Warren Roche

Keyword(s):

Overland Flow ◽

Previous History ◽

Infiltration Rate ◽

Nonlinear Phenomenon ◽

Hysteretic Model ◽

Rainfall Runoff ◽

Total Runoff ◽

History Of ◽

Preisach Operator ◽

Rainfall Runoff Model

<div>The soil can be modelled as a porous medium in which the three phases of matter coexist and produce the emergent phenomenon of hysteresis.</div><div>Rate-independent hysteresis is a nonlinear phenomenon where the output depends not only on the current input but also the previous history of inputs to the system. In multiphase porous media such as soils, the hysteresis is in the relationship between the soil-moisture content, and the capillary pressure.</div><div>In this work, we develop a simplified hysteretic rainfall-runoff model consisting of the following subsystems that capture much of the physics of flow through a slab of soil:</div><div>1) A slab of soil where rainfall enters and if enough water is present in the soil, it will subsequently drain into the groundwater reservoir. This part of the model is represent by ODE with a Preisach operator.</div><div>2) A runoff component: If the rainfall exceeds the maximum infiltration rate of the soil, the excess will become surface runoff. This part of the model is represented by a series of two hysteretic reservoirs instead of the two linear reservoirs in the literature.</div><div>3) A ground water storage and outflow subsystem component: this is also modelled by a hysteretic reservoir. Finally, the outputs from the groundwater output and the overland flow are combined to give the total runoff. We will examine this model and compare it with non-hysteretic case both qualitatively and quantitively.</div>

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