Developing an independent, generic, phosphorus modelling component for use with grid-oriented, physically based distributed catchment models

Grid-oriented, physically based catchment models calculate fields of various hydrological variables relevant to phosphorus detachment and transport. These include (i) for surface transport: overland flow depth and flow in the coordinate directions, sediment load, and sediment concentration and (ii) for subsurface transport: soil moisture and hydraulic head at various depths in the soil. These variables can be considered as decoupled from any chemical phosphorus model since phosphorus concentrations, either as dissolved or particulate, do not influence the model calculations of the hydrological fields. Thus the phosphorus concentration calculations can be carried out independently from and after the hydrological calculations. This makes it possible to produce a separate phosphorus modelling component which takes as input the hydrological fields produced by the catchment model and which calculates, at each simulation time step, the phosphorus concentrations in the flows. This paper summarises the equations and structure of such a Grid Oriented Phosphorus Component (GOPC) developed by the authors for simulating phosphorus concentrations and loads using the outputs of a fully distributed physical based hydrological model. The GOPC performance is illustrated by an example of a simplified hypothetical catchment subjected to some ideal conditions.

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The role of the geometry and frequency of rectangular rills in the relationship between sediment concentration and stream power

Soil Research ◽

10.1071/s97019 ◽

1997 ◽

Vol 35 (6) ◽

pp. 1359 ◽

Cited By ~ 2

Author(s):

B. Fentie ◽

C. W. Rose ◽

K. J. Coughlan ◽

C. A. A. Ciesiolka

Keyword(s):

Soil Erosion ◽

Overland Flow ◽

Sediment Concentration ◽

Stream Power ◽

Flume Experiments ◽

Erosion Processes ◽

Physically Based ◽

The Relationship ◽

Raindrop Impact

We examined, both experimentally and theoretically, whether rilling results in higher soil erosion than would have occurred without rilling. The possibility of rilling occurs when overland flow-driven erosion processes are dominant over erosion due to raindrop impact, and that is the situation assumed in this paper. Stream power (or a quantity related to stream power such as shear stress) is commonly used to describe the driving variable in flow-driven erosion. Five flume experiments were designed to investigate the relationship between stream power and sediment concentration and how this relationship is affected by the ratio of width to depth of flow (r), and the frequency or number of rills per metre width (N) of rectangular rills. This paper presents the results of these experiments and uses a physically based soil erosion theory to show that the results of the 5 flume experiments are in accord with this theory. This theory is used to investigate the effect of all possible rectangular rill geometries and frequencies on the maximum possible sediment concentration, i.e. the sediment concentration at the transport limit, by developing general relationships for the influence of r and N on sediment concentration. It is shown that increased stream power, which can be due to rilling, does not necessarily result in higher sediment concentration.

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Simulation of nonpoint source pollutant loadings from urban area during rainfall: an application of a physically-based distributed model

Water Science & Technology ◽

10.2166/wst.1998.0402 ◽

1998 ◽

Vol 38 (10) ◽

pp. 199-206 ◽

Cited By ~ 1

Author(s):

Zhang Haiping ◽

Kiyoshi Yamada

Keyword(s):

Urban Area ◽

Overland Flow ◽

Drainage System ◽

Distributed Model ◽

Storm Event ◽

Urban Watershed ◽

Storm Events ◽

Runoff Generation ◽

Time Step ◽

Physically Based

A physically-based, distributed model, PROUW, is applied to a small urban watershed in Japan with an area of 66.18 ha. The model includes a description of evapotranspiration, percolation, runoff generation, overland flow routing, pollutant accumulation in dry weathers and washoff during storm events, overland pollutant routing, and flow and pollutant routing in drainage system. The finite difference schematization of the urban watershed provides a representation of the spatial pattern of topography, land-use, soil types and meteorological inputs. The watershed is divided into 7500 grids of 10m × 10m and the runoff rate and pollutant loadings are simulated with a time step of 5 sec. The data for the storm event of April 28, 1995 is used for model calibration. Simulated hydrograph and pollutographs of the storm event of April 18, 1995 are compared with the observed data. Results show a reasonable degree of fit, indicating that the model provides a reasonable interpretation of the overall runoff and pollutant generation processes in the urban area. The results also suggest that the model should be improved further by incorporating new reliable equations for pollutant washoff estimation.

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ASSESSMENT OF MAXIMUM INSTANT DISCHARGE OF VARIOUS FREQUENCY AT UNGAUGED MOUNTAINOUS RIVER KHEMCHIK (TUVA REPUBLIC) BASED ON MATHEMATICAL MODELLING

Engineering survey ◽

10.25296/1997-8650-2019-13-2-36-51 ◽

2019 ◽

Vol 13 (2) ◽

pp. 36-51 ◽

Cited By ~ 2

Author(s):

O. M. Makarieva ◽

N. V. Nesterova ◽

G. P. Yampolsky ◽

E. Y. Kudymova

Keyword(s):

Coniferous Forest ◽

Frequency Interval ◽

Time Step ◽

Model Calculations ◽

Runoff Formation ◽

Emergency Situations ◽

Daily Streamflow ◽

Standard Methodology ◽

Maximum Elevation ◽

Daily Time Step

Abstract: the article presents the results of application of distributed deterministic hydrological model Hydrograph for estimation of maximum discharge values of different frequency at the ungauged catchment of the Khemchik River (Khemchik village, Tuva Republic). The catchment area is 1750 km2 , the average and maximum elevation — 2200 and 3600 m, respectively. Due to the lack of detailed information, a schematization of the catchment and the parameterization of the model are proposed, based on general ideas about the water balance and the processes of runoff formation of the main landscapes — rocky talus, coniferous forest and steppe. Parameters and algorithms are verified based on the results of streamflow modeling at two studied catchments: the Tapsy River — Kara-Khol (302 km2 ) and the Khemchik River — Iyme (25500 km2 ). Modelling of runoff formation processes with daily time step for the Khemchik River — Khemchik village was conducted for the period 1966–2012 using observational data at Teeli meteorological station. For the transition from daily to instant discharges, the dependence of the observed values of instant and daily streamflow at the studied gauges has been applied. On the basis of simulated discharge series, the frequency curve was built and the obtained curve was compared with the calculation data according to the standard methodology SP 33-101-2003 “Determination of the main calculated hydrological characteristics” using the analogue river. Simulated maximum instant discharges for entire frequency interval of up to 1% are 1.3–5 times higher than the values obtained by standard methodology SP 33-101-2003. The results of model calculations is indirectly confirmed by the evidences of regular flooding of the Khemchik village provided by the Ministry of Emergency Situations of the Tuva Republic, which is not predicted by the values obtained by the standard methods.

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Sensitivity and Performance Analyses of the Distributed Hydrology–Soil–Vegetation Model Using Geomorphons for Landform Mapping

Water ◽

10.3390/w13152032 ◽

2021 ◽

Vol 13 (15) ◽

pp. 2032

Author(s):

Pâmela A. Melo ◽

Lívia A. Alvarenga ◽

Javier Tomasella ◽

Carlos R. Mello ◽

Minella A. Martins ◽

...

Keyword(s):

Complex Terrain ◽

Overland Flow ◽

Hydrological Model ◽

Model Performance ◽

Soil Parameters ◽

Vegetation Model ◽

Landform Classification ◽

Physically Based ◽

And Performance ◽

Streamflow Simulation

Landform classification is important for representing soil physical properties varying continuously across the landscape and for understanding many hydrological processes in watersheds. Considering it, this study aims to use a geomorphology map (Geomorphons) as an input to a physically based hydrological model (Distributed Hydrology Soil Vegetation Model (DHSVM)) in a mountainous headwater watershed. A sensitivity analysis of five soil parameters was evaluated for streamflow simulation in each Geomorphons feature. As infiltration and saturation excess overland flow are important mechanisms for streamflow generation in complex terrain watersheds, the model’s input soil parameters were most sensitive in the “slope”, “hollow”, and “valley” features. Thus, the simulated streamflow was compared with observed data for calibration and validation. The model performance was satisfactory and equivalent to previous simulations in the same watershed using pedological survey and moisture zone maps. Therefore, the results from this study indicate that a geomorphologically based map is applicable and representative for spatially distributing hydrological parameters in the DHSVM.

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Toward a Robust Canopy Hydrology Scheme with Precipitation Subgrid Variability

Journal of Hydrometeorology ◽

10.1175/jhm585.1 ◽

2007 ◽

Vol 8 (3) ◽

pp. 439-446 ◽

Cited By ~ 13

Author(s):

Dagang Wang ◽

Guiling Wang

Keyword(s):

Land Surface ◽

Surface Characteristics ◽

Hydrological Processes ◽

Canopy Interception ◽

Time Step ◽

Covered Area ◽

Surface Models ◽

Physically Based ◽

Interception Loss ◽

The Impact

Abstract Representation of the canopy hydrological processes has been challenging in land surface modeling due to the subgrid heterogeneity in both precipitation and surface characteristics. The Shuttleworth dynamic–statistical method is widely used to represent the impact of the precipitation subgrid variability on canopy hydrological processes but shows unwanted sensitivity to temporal resolution when implemented into land surface models. This paper presents a canopy hydrology scheme that is robust at different temporal resolutions. This scheme is devised by applying two physically based treatments to the Shuttleworth scheme: 1) the canopy hydrological processes within the rain-covered area are treated separately from those within the nonrain area, and the scheme tracks the relative rain location between adjacent time steps; and 2) within the rain-covered area, the canopy interception is so determined as to sustain the potential evaporation from the wetted canopy or is equal to precipitation, whichever is less, to maintain somewhat wet canopy during any rainy time step. When applied to the Amazon region, the new scheme establishes interception loss ratios of 0.3 at a 10-min time step and 0.23 at a 2-h time step. Compared to interception loss ratios of 0.45 and 0.09 at the corresponding time steps established by the original Shuttleworth scheme, the new scheme is much more stable under different temporal resolutions.

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Analysis of the development of a hydrological balance for future decades in the Senianska depression in the Eastern Slovak lowland

Slovak Journal of Civil Engineering ◽

10.2478/v10189-010-0020-6 ◽

2010 ◽

Vol 18 (4) ◽

pp. 30-40 ◽

Cited By ~ 1

Author(s):

M. Tegelhoffová

Keyword(s):

River Basin ◽

Overland Flow ◽

Water Levels ◽

Water Control ◽

Mike She ◽

Hydrological Balance ◽

Small Water ◽

Model Domain ◽

Physically Based ◽

Set Up

Analysis of the development of a hydrological balance for future decades in the Senianska depression in the Eastern Slovak lowlandThe goal of the article was to analyze the hydrological balance for future decades in a pilot area in the Eastern Slovak lowland. The aim was to set up the physically-based Mike SHE hydrological model for the modeling hydrological balance in the selected wetland ecosystem in the Eastern Slovak Lowland. The pilot area - the Senianska depression is located near the village of Senne, between the Laborec and Uh Rivers. Specifically, it is a traditional landscape of meadows, marshes, cultivated soil, small water control structures and forests. To get a complete model set up for simulating elements of the hydrologic balance in the pilot area, it was necessary to devise a model for a larger area, which includes the pilot area - the Senianska depression. Therefore, both the Mike SHE model was set up for the Laborec River basin (a model domain of 500 × 500 m) and the Čierna voda River basin (a model domain of 100 × 100 m), for the simulation period of 1981-2007, is order to get the boundary conditions (overland flow depth, water levels, discharges and groundwater table) for the model of the pilot area. The Mike SHE model constructed for the pilot area - the Senianska depression (a model domain of 1 × 1 m) -was used to simulate the elements of the hydrological balance for the existing conditions during the simulation period of 1983-2007 and for climate scenarios for the simulation period of 1983-2100. The results of the simulated elements of the hydrological balance for the existing conditions were used for a comparison of the evolution of the hydrologic conditions in the past, for identifying wet and flooded areas and for identifying the spatial distribution of the actual evapotranspiration in the pilot area. The built-up model with setting values was used for modeling the hydrological balance in changed conditions - climate change.

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Physically-based modelling of hydrological processes in a tropical headwater catchment (West Africa) – process representation and multi-criteria validation

Hydrology and Earth System Sciences ◽

10.5194/hess-10-829-2006 ◽

2006 ◽

Vol 10 (6) ◽

pp. 829-847 ◽

Cited By ~ 45

Author(s):

S. Giertz ◽

B. Diekkrüger ◽

G. Steup

Keyword(s):

Soil Moisture ◽

Rainy Season ◽

Overland Flow ◽

Soil Layer ◽

Hydrological Processes ◽

Runoff Generation ◽

Field Investigations ◽

Physically Based ◽

In The Beginning ◽

Headwater Catchment

Abstract. The aim of the study was to test the applicability of a physically-based model to simulate the hydrological processes in a headwater catchment in Benin. Field investigations in the catchment have shown that lateral processes such as surface runoff and interflow are most important. Therefore, the 1-D SVAT-model SIMULAT was modified to a semi-distributed hillslope version (SIMULAT-H). Based on a good database, the model was evaluated in a multi-criteria validation using discharge, discharge components and soil moisture data. For the validation of discharge, good results were achieved for dry and wet years. The main differences were observable in the beginning of the rainy season. A comparison of the discharge components determined by hydro-chemical measurements with the simulation revealed that the model simulated the ratio of groundwater fluxes and fast runoff components correctly. For the validation of the discharge components of single events, larger differences were observable, which was partly caused by uncertainties in the precipitation data. The representation of the soil moisture dynamics by the model was good for the top soil layer. For deeper soil horizons, which are characterized by higher gravel content, the differences between simulated and measured soil moisture were larger. A good agreement of simulation results and field investigations was achieved for the runoff generation processes. Interflow is the predominant process on the upper and the middle slopes, while at the bottom of the hillslope groundwater recharge and – during the rainy season – saturated overland flow are important processes.

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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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