Surface runoff and soil water percolation as affected by snow and soil frost

Surface runoff can represent a significant part of the hydrological balance of grazed pastures on the north-west slopes of New South Wales, and is influenced by a range of rainfall characteristic, soil property, and pasture conditions. Runoff plots were established on grazed pastures at 3 sites as part of the Sustainable Grazing Systems National Experiment (SGS NE). Pastures were either native (redgrass, wallaby grass and wire grass) or sown species (phalaris, subterranean clover and lucerne) and a range of grazing management treatments were imposed to manipulate pasture herbage mass, litter mass and ground cover. Rainfall and runoff events were recorded using automatic data loggers between January 1998 and September 2001. Stored soil water in the surface layer (0–22.5 cm) was monitored continuously using electrical resistance sensors and automatic loggers. Pasture herbage mass, litter mass and ground cover were estimated regularly to provide information useful in interpreting runoff generation processes.Total runoff ranged from 6.6 mm at Manilla (0.3% of rainfall) to 185 mm at Nundle (5.7% of rainfall) for different grazing treatments, with the largest runoff event being recorded at Nundle (46.7 mm). Combined site linear regression analyses showed that soil depth, rainfall depth and rainfall duration explained up to 30.3% of the variation in runoff depth. For individual sites, these same variables were also important, accounting for 13.3–33.6% of the variation in runoff depth. Continuous monitoring of stored soil water in relation to these runoff events indicated that the majority of these events were generated by saturation excess, with major events in winter contributing substantially to regional flooding. Long-term simulation modelling (1957–2001) using the SGS Pasture Model indicated that most runoff events were generated in summer, which concurred with the number of flood events recorded at Gunnedah, NSW, downstream of the SGS sites. However, floods also occurred frequently in winter, but the simulations generated few runoff events at that time of the year. These results have important implications for sustainability of grazed pastures and long-term simulation modelling of the hydrological balance of such systems, since runoff generation processes are likely to vary both spatially and temporally for different rainfall events.

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Surface soil water dynamics in pastures in northern New South Wales. 1. Use of electrical resistance sensors

Australian Journal of Experimental Agriculture ◽

10.1071/ea03026 ◽

2004 ◽

Vol 44 (3) ◽

pp. 273 ◽

Cited By ~ 5

Author(s):

S. R. Murphy ◽

G. M. Lodge

Keyword(s):

Water Content ◽

Soil Water ◽

Real Time ◽

Surface Runoff ◽

Electrical Resistance ◽

New South ◽

Water Dynamics ◽

Continuous Data ◽

Soil Water Dynamics ◽

South Wales

Stored soil water may influence both the generation of surface runoff and the rate of evapotranspiration from pastures, which may be significant in northern New South Wales. Continuous data is essential to fully understand these processes in field studies. Electrical resistance sensors were used to capture continuous data and they were calibrated directly for soil water content (SWC), so as to provide quantitative data in real time. Calibration equations (logarithmic regression) were significantly different for a range of installation depths (2.5–20 cm). To�provide quantitative insight into soil water dynamics in studies of stored soil water, surface runoff, and evapotranspiration, real time data were collected at intervals ranging from 4 min to 24 h. Resistance sensors provided estimates of stored soil water (0–30 cm) that differed by up to 29% compared with estimates obtained from using a neutron moisture metre alone. In surface runoff studies, data collected at 4 min intervals showed that runoff was generated when soil water content was high. In studies of evapotranspiration, daily data were used to quantify different evapotranspiration rates (2.3–4.9 mm/day) and progressive depth of drying for a range of treatments. We concluded that data collected in real time using resistance sensors may be used to make better estimates of SWC and so improve the interpretation of surface runoff generation and evapotranspiration data.

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Quantitative Analysis of Hydrological Responses to Climate Variability and Land-Use Change in the Hilly-Gully Region of the Loess Plateau, China

Water ◽

10.3390/w12010082 ◽

2019 ◽

Vol 12 (1) ◽

pp. 82 ◽

Cited By ~ 1

Author(s):

Youcai Kang ◽

Jianen Gao ◽

Hui Shao ◽

Yuanyuan Zhang

Keyword(s):

Land Use ◽

Land Use Change ◽

Climate Variability ◽

Soil Water ◽

Loess Plateau ◽

Surface Runoff ◽

Water Resource Management ◽

Assessment Tool ◽

Upstream Region ◽

The Loess Plateau

Climate and land-use change are the two main driving forces that affect watershed hydrological processes. Separately assessing their impacts on hydrology is important for land-use planning and water resource management. In this research, the SWAT (Soil and Water Assessment Tool) and statistical methods were applied to evaluate the effects of climate and land-use change on surface hydrology in the hilly-gully region of the Loess Plateau. The results showed that surface runoff and soil water presented a downward tendency, while evapotranspiration (ET) presented an upward tendency in the Yanhe watershed from 1982 to 2012. Climate is one the dominant factors that influence surface runoff, especially in flooding periods. The average contribution rate of surface runoff on stream flow accounted for 55%, of which the flooding period accounted for 40%. The runoff coefficient declined by 0.21 after 2002 with the land-use change of cropland transformed to grassland and forestland. The soil water exhibited great fluctuation along the Yanhe watershed. In the upstream region, the land-use was the driving force to decline soil water, which reduced the soil water by 51%. Along the spatial distribution, it converted from land-use change to climate variability from northwest to southeast. The ET was more sensitive to land-use change than climate variability in all sub-basins, and increased by 209% with vegetation restoration. To prevent the ecosystem degradation and maintain the inherent ecological functions of rivers, quantitative assessment the influence of climate variability and land-use change on hydrology is of great importance. Such evaluations can provide insight into the extent of land use/cover change on regional water balance and develop appropriate watershed management strategies on the Loess Plateau.

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SURFACE RUNOFF AND LATERAL SUBSURFACE FLOW AS A RESPONSE TO CONSERVATION TILLAGE AND SOIL-WATER CONDITIONS

Transactions of the ASAE ◽

10.13031/2013.20099 ◽

2005 ◽

Vol 48 (6) ◽

pp. 2137-2144 ◽

Cited By ~ 25

Author(s):

D. D. Bosch ◽

T. L. Potter ◽

C. C. Truman ◽

C. W. Bednarz ◽

T. C. Strickland

Keyword(s):

Soil Water ◽

Surface Runoff ◽

Conservation Tillage ◽

Subsurface Flow ◽

Water Conditions ◽

Soil Water Conditions

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Study on Variation of Surface Runoff and Soil Moisture Content in the Subgrade of Permeable Pavement Structure

Advances in Civil Engineering ◽

10.1155/2020/8836643 ◽

2020 ◽

Vol 2020 ◽

pp. 1-12

Author(s):

Lijun Hou ◽

Yuan Wang ◽

Fengchun Shen ◽

Ming Lei ◽

Xiang Wang ◽

...

Keyword(s):

Soil Moisture ◽

Moisture Content ◽

Soil Water ◽

Surface Runoff ◽

Rainfall Intensity ◽

Soil Moisture Content ◽

Asphalt Pavement ◽

Infiltration Rate ◽

Runoff Coefficient ◽

Flood Peak

The self-designed indoor simulated rainfall device was used to rain on five types of pavement structures with 4 types of rainfall intensity (2.5 mm/min, 3.4 mm/min, 4.6 mm/min, and 5.5 mm/min). The effect of rainfall intensity on the surface runoff, the relation between the subgrade soil moisture content changes, and the influence of initial soil water content on rain infiltration rate are studied. The test results show that the surface runoff coefficient of densely asphalted pavement is greater than 90% in drainage pavements and it has little influence on the reducing and hysteresis of the flood peak. The surface runoff coefficient of large-void asphalt pavement (permeable) is less than 40%. Although the large-void asphalt pavement (permeable) can reduce a small amount of surface runoff, it has no obvious effect on the reduction and hysteresis of the flood peak. In semipermeable pavement, with the increasing of the thickness of base (graded gravel), the surface runoff coefficient decreases at different rainfall intensities, parts of the surface runoff are reduced, and the arrival of flood peaks is delayed. In permeable roads, almost no surface runoff occurred. As time continued, the soil moisture content quickly reached a saturated state and presented a stable infiltration situation under the action of gravity and the gradient of soil water suction. As the initial moisture content increases, the initial infiltration rate decreases and the time to reach a stable infiltration rate becomes shorter. The drier the soil, the greater the initial infiltration rate and the higher the soil moisture content after infiltration stabilization. Permeable roads can greatly alleviate the pressure of urban drainage and reduce the risk of storms and floods.

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The effect of soil moisture extremes on the pathways and forms of phosphorus lost in runoff from two contrasting soil types

Soil Research ◽

10.1071/sr15324 ◽

2017 ◽

Vol 55 (1) ◽

pp. 19 ◽

Cited By ~ 7

Author(s):

B. Simmonds ◽

R. W. McDowell ◽

L. M. Condron

Keyword(s):

Soil Moisture ◽

Soil Water ◽

Surface Runoff ◽

Water Drop ◽

Organic Soil ◽

Surface Flow ◽

Olsen P ◽

Excess Surface ◽

Infiltration Excess ◽

Penetration Time

Soil moisture and Olsen P concentrations play an important role in phosphorus (P) losses in runoff. Under moisture-rich anaerobic conditions, the reduction of Fe-oxides dissolves P from the soil into solution that may be available for loss by transport processes. Under very dry conditions, soil hydrophobicity induced by soil organic C can exacerbate infiltration-excess surface flow and soil erosion. Our hypotheses were as follows: (1) rainfall applied to a dry soil would cause greater particulate P losses in surface runoff due to hydrophobicity; (2) P losses from a wet soil would be dominated by drainage and filtered P; and (3) both runoff processes would result in environmentally unacceptable P losses at agronomically productive Olsen P concentrations depending on the sorption capacity (anion storage capacity; ASC) of the soil. Superphosphate was added to a Brown and Organic soil (Olsen P initially 7 and 13mgL–1 respectively) to create a range of Olsen P concentrations. Soils were placed in boxes, soil moisture adjusted (<10% or 90% available water holding capacity) and artificial rainfall applied at a rate equivalent to a storm event (5-year return interval; 30–35mmh–1) and surface runoff and drainage collected. Surface runoff was measured as infiltration-excess surface flow from dry Organic soil (water drop penetration time >3600s), and as saturation-excess surface flow from the wet Brown soil (water drop penetration time <5s). Total P (TP) concentrations in surface flow from both soils increased linearly with Olsen P concentration. Compared with dry Organic soil, the wet Brown soil lost a greater proportion of TP as particulate via surface runoff. However, due to the high hydraulic conductivity and low ASC, the most important pathway for the Organic soil, wet or dry, was filtered P loss in drainage. These data can be used to more effectively target strategies to mitigate P losses.

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Seasonal variation of 24D export through surface runoff from pasture

New Zealand Plant Protection ◽

10.30843/nzpp.2006.59.4411 ◽

2006 ◽

Vol 59 ◽

pp. 255-260 ◽

Cited By ~ 1

Author(s):

K. M?ller ◽

R. Stenger ◽

A. Rahman

Keyword(s):

Seasonal Variation ◽

Soil Water ◽

Surface Runoff ◽

Rainfall Simulator ◽

Water Conditions ◽

Infiltration Excess ◽

Soil Water Conditions ◽

Saturation Excess

One day after the herbicide 24D was applied to 1050 m2 of a pastoral hillslope in Waikato runoff was generated with a sprinklertype rainfall simulator and 24D transport in surface runoff was measured The runoff coefficients differed significantly between an autumn (47) and a spring (19) event in spite of similar preevent soil water conditions Saturation excess with a variable contributing area had earlier been identified as the main runoff generating process for the autumn event In contrast infiltration excess possibly induced by treading effects and hydrophobicity are proposed as runoff causing processes for the spring event The eventaveraged 24D concentration in runoff was higher in autumn (049 mg/litre) than in spring (024 mg/litre) Correspondingly the exported 24D loss in autumn totalled 75 g/ha which equals 7 of the applied mass compared to only 14 g/ha (or 1) during the spring event

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Biomechanics of Surface Runoff and Soil Water Percolation

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.401.36 ◽

2020 ◽

Vol 401 ◽

pp. 36-46

Author(s):

James Makol Madut Deng ◽

Oluwole Daniel Makinde

Keyword(s):

Heat Transfer ◽

Porous Medium ◽

Soil Water ◽

Heat Transfer Rate ◽

Surface Runoff ◽

Transfer Rate ◽

Soil Surface ◽

Biophysical Parameters ◽

Two Phase ◽

Soil Water Transport

In this study, the complex interaction of surface runoff with the biomechanics of soil water transport and heat transfer rate is theoretically investigated using a mathematical model that relies on the two phase flows of an incompressible Newtonian fluid (stormwater) within the soil (porous medium) and on the soil surface (runoff). The flow and heat transfer characteristics within the soil are determined numerically based on Darcy-Brinkman-Forchheimer model for porous medium coupled with the appropriate energy equation while analytical approach is employed to tackle the model for interacting surface runoff stormwater. The effects of various embedded biophysical parameters on the temperature distribution and stormwater transport within the soil and across the soil surface together with soil-runoff interface skin friction and Nusselt number are display graphically and discussed quantitatively. It is found that an increase in surface runoff over tightly packed soil lessens stormwater percolation rate but enhances both soil erosion and surface heat transfer rate.

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