Surface Runoff Generation and Soil Loss Under Different Soil and Rainfall Properties in The Uluguru Mountains, Tanzania

Abstract. A conceptual water balance model is presented to represent changes in monthly water balance following land use changes. Monthly rainfall–runoff, groundwater and soil moisture data from four experimental catchments in Western Australia have been analysed. Two of these catchments, "Ernies" (control, fully forested) and "Lemon" (54% cleared) are in a zone of mean annual rainfall of 725 mm, while "Salmon" (control, fully forested) and "Wights" (100% cleared) are in a zone with mean annual rainfall of 1125 mm. At the Salmon forested control catchment, streamflow comprises surface runoff, base flow and interflow components. In the Wights catchment, cleared of native forest for pasture development, all three components increased, groundwater levels rose significantly and stream zone saturated area increased from 1% to 15% of the catchment area. It took seven years after clearing for the rainfall–runoff generation process to stabilise in 1984. At the Ernies forested control catchment, the permanent groundwater system is 20 m below the stream bed and so does not contribute to streamflow. Following partial clearing of forest in the Lemon catchment, groundwater rose steadily and reached the stream bed by 1987. The streamflow increased in two phases: (i) immediately after clearing due to reduced evapotranspiration, and (ii) through an increase in the groundwater-induced stream zone saturated area after 1987. After analysing all the data available, a conceptual monthly model was created, comprising four inter-connecting stores: (i) an upper zone unsaturated store, (ii) a transient stream zone store, (ii) a lower zone unsaturated store and (iv) a saturated groundwater store. Data such as rooting depth, Leaf Area Index, soil porosity, profile thickness, depth to groundwater, stream length and surface slope were incorporated into the model as a priori defined attributes. The catchment average values for different stores were determined through matching observed and predicted monthly hydrographs. The observed and predicted monthly runoff for all catchments matched well with coefficients of determination (R2) ranging from 0.68 to 0.87. Predictions were relatively poor for: (i) the Ernies catchment (lowest rainfall, forested), and (ii) months with very high flows. Overall, the predicted mean annual streamflow was within ±8% of the observed values. Keywords: monthly streamflow, land use change, conceptual model, data-based approach, groundwater

Download Full-text

Spatio-temporal modeling of surface runoff in ungauged sub-catchments of Subarnarekha river basin using SWAT

MAUSAM ◽

10.54302/mausam.v72i3.1309 ◽

2021 ◽

Vol 72 (3) ◽

pp. 597-606

Author(s):

CHINMAYA PANDA ◽

DWARIKA MOHAN DAS ◽

B. C. SAHOO ◽

B. PANIGRAHI ◽

K. K. SINGH

Keyword(s):

Surface Runoff ◽

Assessment Tool ◽

Nutrient Loss ◽

Coefficient Of Determination ◽

Annual Rainfall ◽

Model Parameters ◽

Runoff Generation ◽

Temporal Modeling ◽

Spatio Temporal ◽

R Factors

In this present study, Soil and Water Assessment Tool (SWAT) embedded with ArcGIS interface has been used to simulate the surface runoff from the un-gauged sub-catchments in the upper catchment of Subarnarekha basin. Model calibration and validation were performed with the help of Sequential Uncertainty Fitting (SUFI-2) in-built in the SWAT-CUP package (SWAT Calibration Uncertainty Programs). The model was calibrated for a period from 1996 to 2008 with 3 years warm up period (1996-1998) and validated for a period of 5 years from 2009 to 2013. The model evaluation was performed by Nash - Sutcliffe coefficient (NSE), Coefficient of determination (R2) and Percentage Bias (PBIAS). The degree of uncertainty was evaluated by P and R factors. Basing upon the R2, NSE and PBIAS values respectively, of the order of 0.90, 0.90 and -12%, during calibration and 0.85, 0.83 and -15% during validation, substantiate performance of the model. All uncertainties of model parameters have been well taken by the P and R factors respectively, of the order of 0.95 and 0.77 during calibration and 0.82 and 0.87 during validation. The runoff generation from 19 sub-catchments of Adityapur catchment varies from 29.2-44.1% of the annual rainfall and average surface runoff simulated for the entire catchment is 545 mm. As the surface runoff generated in most of the sub-catchments amounts to above 30% of rainfall, it is recommended for adequate number of structural interventions at appropriate locations in the catchment to store the rainfall excess for providing irrigation, recharging groundwater and restricting the sediment and nutrient loss.

Download Full-text

Rainfall and Surface Roughness Effects on Soil Loss and Surface Runoff

10.13031/2013.4577 ◽

2013 ◽

Author(s):

W. Jester ◽

A. Klik ◽

G. Hauer ◽

B. Hebel ◽

C. C. Truman

Keyword(s):

Surface Roughness ◽

Surface Runoff ◽

Soil Loss ◽

Roughness Effects

Download Full-text

Effects of gravel-sand mulch on the runoff, erosion, and nutrient losses in the Loess Plateau of north-western China under simulated rainfall

Soil and Water Research ◽

10.17221/141/2019-swr ◽

2020 ◽

Vol 16 (No. 1) ◽

pp. 22-28

Author(s):

Yang Qiu ◽

Xinping Wang ◽

Zhongkui Xie ◽

Yajun Wang

Keyword(s):

Grain Size ◽

Surface Runoff ◽

Soil Loss ◽

Bare Soil ◽

Western China ◽

Nutrient Losses ◽

Gravel Mulch ◽

Runoff And Soil Loss ◽

North Western ◽

Fine Gravel

Gravel mulching is a characteristic agricultural technique that has been used for hundreds of years in the north-western Loess Plateau of China. However, the effects of the gravel-sand mulch on the processes of the runoff, soil erosion, and nutrient losses are neither fully distinguished nor even known in many parts of the world. This study investigated how different gravel particle sizes in the mulch affected the runoff, erosion as well as the extent of the nutrient losses in the surface runoff. The laboratory experiments were conducted using a rainfall simulator with three gravel mulch treatments: (1) fine gravel mulch (FG); (2) medium gravel mulch (MG); (3) coarse gravel mulch (CG) and a control group, bare soil (BS). The results of these rainfall simulation experiments gave estimates on how the grain size influences the runoff and losses of the soil and its nutrients. Applying the gravel mulch significantly delayed the runoff’s starting time when compared with the bare soil. Both the total runoff and soil loss increased with the grain size of the gravel mulch. Compared with the bare soil, the lowest surface runoff and soil loss was observed from the fine gravel treatment. These results clearly show that gravel mulch plays an important role in the runoff and sediment generation processes, and that it significantly reduces the surface runoff and soil loss. The losses of the total nitrogen (TN), total phosphorus (TP), and total organic carbon (TOC) from the bare soil were much higher than those under the gravel mulching. The fluctuations in these nutrient-loss processes were the most intense in the CG treatment, while the TC content, in initial runoff, was significantly higher in the FG than the other treatments. Our findings suggest gravel mulch is a useful water and soil conservation technique in the loess area of north-western China, and these results can inform one on the theoretical principles for properly utilising gravel-mulched fields.

Download Full-text

Surface soil water dynamics in pastures in northern New South Wales. 2. Surface runoff

Australian Journal of Experimental Agriculture ◽

10.1071/ea03027 ◽

2004 ◽

Vol 44 (3) ◽

pp. 283 ◽

Cited By ~ 7

Author(s):

S. R. Murphy ◽

G. M. Lodge ◽

S. Harden

Keyword(s):

Soil Water ◽

Surface Runoff ◽

New South ◽

Ground Cover ◽

Simulation Modelling ◽

Runoff Generation ◽

Grazed Pastures ◽

South Wales ◽

Runoff Events

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.

Download Full-text

The effects of Rubus hyrcanus L. and Philonotis marchica (Hedw.) Brid. on soil loss prevention from cutslopes of a forest road

Journal of Forest Science ◽

10.17221/9/2012-jfs ◽

2012 ◽

Vol 58 (No. 8) ◽

pp. 337-344 ◽

Cited By ~ 3

Author(s):

A. Parsakhoo ◽

M. Lotfalian ◽

A. Kavian ◽

S.A. Hosseini ◽

M. Demir

Keyword(s):

Soil Loss ◽

Sediment Concentration ◽

Rainfall Simulation ◽

Runoff Generation ◽

Forest Roads ◽

Northern Forest ◽

Forest Road ◽

Runoff And Soil Loss ◽

The City ◽

Runoff And Sedimentation

The effects of Rubus hyrcanus L. and Philonotis marchica (Hedw.) Bridon on runoff generation and soil loss from cutslopes of forest roads were investigated. The study was conducted at the northern forest of Iran, about 30 km south of the city of Sari. Runoff and sedimentation after each rainfall simulation and chemical and physical soil properties were measured in 14 plots with an area of 0.48 m2. The obtained results indicate that the vegetation dominated by Philonotis marchica exhibited the higher runoff coefficient and soil loss, with averages of 27.25% and 92.40 g·m–2·h–1(gram per square meter per hour), respectively, in comparison to Rubus hyrcanus. For Philonotis marchica (Hedw.) Brid. the sediment concentration increased quickly at the beginning of rainfall simulations and after 10–12 min there was a fast decrease in sediment concentration. The peak of sediment concentration was for the Rubus hyrcanus L. in the 13th–15th min In conclusion, Rubus hyrcanus L. prevented or decreased the risk of runoff and soil loss from cutslopes of forest roads in our study area.

Download Full-text

Effect of Tillage on Surface Runoff and Soil Loss from Cotton

Transactions of the ASAE ◽

10.13031/2013.30421 ◽

1987 ◽

Vol 30 (1) ◽

pp. 0166-0168 ◽

Cited By ~ 1

Author(s):

Kyung H. Yoo ◽

J. T. Touchton ◽

R. H. Walker

Keyword(s):

Surface Runoff ◽

Soil Loss ◽

Runoff And Soil Loss

Download Full-text

Investigating the effective factors influencing surface runoff generation in urban catchments – A review

10.5004/dwt.2019.24359 ◽

2019 ◽

Vol 164 ◽

pp. 276-292

Author(s):

Abdul Razaq Rezaei ◽

Zubaidah Binti Ismail ◽

Mohammad Hossein Niksokhan ◽

Abu Hanipah Ramli ◽

Lariyah Mohd Sidek ◽

...

Keyword(s):

Surface Runoff ◽

Runoff Generation ◽

Effective Factors ◽

Factors Influencing ◽

Urban Catchments

Download Full-text

Improving the representation of the prairie pothole dynamics in land surface models

10.5194/egusphere-egu2020-3713 ◽

2020 ◽

Author(s):

Mohamed I. Ahmed ◽

Amin Elshorbagy ◽

Alain Pietroniro

Keyword(s):

Surface Runoff ◽

Land Surface ◽

Flow Simulation ◽

Hydrologic Model ◽

Surface Model ◽

Prairie Pothole ◽

Runoff Generation ◽

Dem Resolution ◽

Physically Based ◽

Streamflow Simulation

The hydrography of the prairie basins is complicated by the existence of numerous land depressions, known as prairie potholes, which can retain a substantial amount of surface runoff. Consequently, the runoff production in the prairies follows a fill, spill, and merging mechanism, which results in a dynamic contributing area that makes the streamflow simulation challenging. Existing approaches to represent the potholes&#8217; dynamics, in different hydrological models, use either a lumped or a series of reservoirs that contribute flow after exceeding a certain storage threshold. These approaches are simplified and do not represent the actual dynamics of the potholes nor their spatial water extents. Consequently, these approaches may not be useful in capturing the potholes&#8217; complexities and may not be able to accurately simulate the complex prairie streamflow. This study advances towards more accurate and physically-based streamflow simulation in the prairies by implanting a physically-based runoff generation algorithm (Prairie Region Inundation MApping, PRIMA model) within the MESH land surface model, and is referred to as MESH-PRIMA. PRIMA is a recently developed hydrological routing model that can simulate the lateral movement of water over prairie landscape using topographic data provided via DEMs. In MESH-PRIMA, MESH handles the vertical water balance calculations, whereas PRIMA routes the water and determines the amount of water storage and surface runoff. The streamflow simulations of MESH-PRIMA (using different DEM resolution as a topographic input) and MESH with its existing conceptual pothole dynamics algorithm are tested on a number of pothole-dominated watersheds within Saskatchewan, Canada, and compared against observed flows. MESH-PRIMA provides improved streamflow and peak flow simulation, compared to that of MESH with its conceptual pothole algorithm, based on the metrics evaluated for the simulations. MESH-PRIMA shows potential for simulating the actual pothole water extents when compared against water areas obtained from remote sensing data. The use of different DEM resolution changes the resulting pothole water extent, especially for the small potholes as they are not detected in the coarse DEM. MESH-PRIMA can be considered as a hydraulic-hydrologic model that can be used for better understanding and accurate representation of the complex prairie hydrology.

Download Full-text