Quantify the effects of watershed subdivision scale and spatial density of weather inputs on hydrological simulations in a Norwegian Arctic watershed

Abstract The effects of watershed subdivisions on hydrological simulations have not been evaluated in the Arctic conditions yet. This study applied the Soil and Water Assessment Tool and the threshold drainage area (TDA) technique to evaluate the impacts of watershed subdivision on hydrological simulations at a 5,913-km2 Arctic watershed, Målselv. The watershed was discretized according to four TDA scheme scales including 200, 2,000, 5,000, and 10,000 ha. The impacts of different TDA schemes on hydrological simulations in water balance components, snowmelt runoff, and streamflow were investigated. The study revealed that the complexity of terrain and topographic attributes altered significantly in the coarse discretizations: (1) total stream length (−47.2 to −74.6%); (2) average stream slope (−68 to −83%); and (3) drainage density (−24.2 to −51.5%). The spatial density of weather grid integration reduced from −5 to −33.33% in the coarse schemes. The annual mean potential evapotranspiration, evapotranspiration, and lateral flow slightly decreased, while areal rainfall, surface runoff, and water yield slightly increased with the increases of TDAs. It was concluded that the fine TDAs produced finer and higher ranges of snowmelt runoff volume across the watershed. All TDAs had similar capacities to replicate the observed tendency of monthly mean streamflow hydrograph, except overestimated/underestimated peak flows. Spatial variation of streamflow was well analyzed in the fine schemes with high density of stream networks, while the coarse schemes simplified this. Watershed subdivisions affected model performances, in the way of decreasing the accuracy of monthly streamflow simulation, at 60% of investigated hydro-gauging stations (3/5 stations) and in the upstream. Furthermore, watershed subdivisions strongly affected the calibration process regarding the changes in sensitivity ranking of 18 calibrated model parameters and time it took to calibrate.

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Hydrologic modeling of a Himalayan mountain basin by using the SWAT mode

10.5194/hess-2017-100 ◽

2017 ◽

Cited By ~ 3

Author(s):

Sharad K. Jain ◽

Sanjay K. Jain ◽

Neha Jain ◽

Chong-Yu Xu

Keyword(s):

Assessment Tool ◽

Swat Model ◽

Large Population ◽

Water Yield ◽

Model Parameters ◽

Hydrologic Response ◽

Water Balance Components ◽

Daily Streamflow ◽

Hydropower Potential ◽

Himalayan Mountain

Abstract. A large population depends on runoff from Himalayan rivers which have high hydropower potential; floods in these rivers are also frequent. Current understanding of hydrologic response mechanism of these rivers and impact of climate change is inadequate due to limited studies. This paper presents results of modeling to understand the hydrologic response and compute the water balance components of a Himalayan river basin in India viz. Ganga up to Devprayag. Soil and Water Assessment Tool (SWAT) model was applied for simulation of the snow/rainfed catchment. SWAT was calibrated with daily streamflow data for 1992–98 and validated with data for 1999–2005. Manual calibration was carried out to determine model parameters and quantify uncertainty. Results indicate good simulation of streamflow; main contribution to water yield is from lateral and ground water flow. Water yield and ET for the catchments varies between 43–46 % and 57–58 % of precipitation, respectively. The contribution of snowmelt to lateral runoff for Ganga River ranged between 13–20 %. More attention is needed to strengthen spatial and temporal hydrometeorological database for the study basins for improved modeling.

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Estimation of Water Balance Components of Watersheds in the Manjira River Basin using SWAT Model and GIS

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.c6431.029320 ◽

2020 ◽

Vol 9 (3) ◽

pp. 3898-3907

Keyword(s):

Water Balance ◽

River Basin ◽

Assessment Tool ◽

Potential Evapotranspiration ◽

Swat Model ◽

Geographical Information ◽

Weather Data ◽

Water Yield ◽

Water Balance Components ◽

Rain Data

This study mainly focus on hydrological behavior of watersheds in The Manjira River basin using soil and water assessment tool (SWAT) and Geographical information system (GIS). The water balance components for watersheds in the Manjira River were determined by using SWAT model and GIS. Determination of these water balance components helps to study direct and indirect factors affecting characteristics of selected watersheds. Manjira River contains total 28 watersheds among them 2 were selected having watershed code as MNJR008 and MNJR011 specified by the Central Ground Water Board. The SWAT input data such as Digital elevation model (DEM), land use and land cover (LU/LC), Soil classification, slope and weather data was collected. Using these inputs in SWAT the different water balancing components such as rainfall, baseflow, surface runoff, evapotranspiration (ET), potential evapotranspiration (PET) and water yield for each watershed were determined. The evaluated data is then validated by Regression analysis, in which two datasets were compared. Simulated rain data from SWAT simulation and observed rain data from Global Weather Data for SWAT was selected for comparison for each watershed.

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Multi-site calibration and validation of SWAT with satellite-based evapotranspiration in a data-sparse catchment in southwestern Nigeria

Hydrology and Earth System Sciences ◽

10.5194/hess-23-1113-2019 ◽

2019 ◽

Vol 23 (2) ◽

pp. 1113-1144 ◽

Cited By ~ 12

Author(s):

Abolanle E. Odusanya ◽

Bano Mehdi ◽

Christoph Schürz ◽

Adebayo O. Oke ◽

Olufiropo S. Awokola ◽

...

Keyword(s):

Soil Moisture ◽

River Basin ◽

Model Calibration ◽

Hydrological Model ◽

Assessment Tool ◽

Potential Evapotranspiration ◽

Swat Model ◽

Water Balance Components ◽

Southwestern Nigeria ◽

Calibration And Validation

Abstract. The main objective of this study was to calibrate and validate the eco-hydrological model Soil and Water Assessment Tool (SWAT) with satellite-based actual evapotranspiration (AET) data from the Global Land Evaporation Amsterdam Model (GLEAM_v3.0a) and from the Moderate Resolution Imaging Spectroradiometer Global Evaporation (MOD16) for the Ogun River Basin (20 292 km2) located in southwestern Nigeria. Three potential evapotranspiration (PET) equations (Hargreaves, Priestley–Taylor and Penman–Monteith) were used for the SWAT simulation of AET. The reference simulations were the three AET variables simulated with SWAT before model calibration took place. The sequential uncertainty fitting technique (SUFI-2) was used for the SWAT model sensitivity analysis, calibration, validation and uncertainty analysis. The GLEAM_v3.0a and MOD16 products were subsequently used to calibrate the three SWAT-simulated AET variables, thereby obtaining six calibrations–validations at a monthly timescale. The model performance for the three SWAT model runs was evaluated for each of the 53 subbasins against the GLEAM_v3.0a and MOD16 products, which enabled the best model run with the highest-performing satellite-based AET product to be chosen. A verification of the simulated AET variable was carried out by (i) comparing the simulated AET of the calibrated model to GLEAM_v3.0b AET, which is a product that has different forcing data than the version of GLEAM used for the calibration, and (ii) assessing the long-term average annual and average monthly water balances at the outlet of the watershed. Overall, the SWAT model, composed of the Hargreaves PET equation and calibrated using the GLEAM_v3.0a data (GS1), performed well for the simulation of AET and provided a good level of confidence for using the SWAT model as a decision support tool. The 95 % uncertainty of the SWAT-simulated variable bracketed most of the satellite-based AET data in each subbasin. A validation of the simulated soil moisture dynamics for GS1 was carried out using satellite-retrieved soil moisture data, which revealed good agreement. The SWAT model (GS1) also captured the seasonal variability of the water balance components at the outlet of the watershed. This study demonstrated the potential to use remotely sensed evapotranspiration data for hydrological model calibration and validation in a sparsely gauged large river basin with reasonable accuracy. The novelty of the study is the use of these freely available satellite-derived AET datasets to effectively calibrate and validate an eco-hydrological model for a data-scarce catchment.

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Linking Climate, Basin Morphology and Vegetation Characteristics to Fu’s Parameter in Data Poor Conditions

Water ◽

10.3390/w11112333 ◽

2019 ◽

Vol 11 (11) ◽

pp. 2333 ◽

Cited By ~ 1

Author(s):

Dario Ruggiu ◽

Francesco Viola

Keyword(s):

Water Balance ◽

Potential Evapotranspiration ◽

Seasonal Pattern ◽

Computational Effort ◽

Model Parameters ◽

Large Set ◽

Regression Equations ◽

Water Balance Components ◽

Water Partitioning

The prediction of long term water balance components is not a trivial issue, even when empirical Budyko’s type approaches are used, because parameter estimation is often hampered by missing or poor hydrological data. In order to overcome this issue, we provided regression equations that link climate, morphological, and vegetation parameters to Fu’s parameter. Climate is here defined as a specific seasonal pattern of potential evapotranspiration and rain: five climatic scenarios have been considered to mimic different conditions worldwide. A weather generator has been used to create stochastic time series for the related climatic scenario, which in turn has been used as an input to a conceptual hydrological model to obtain long-term water balance components with low computational effort, while preserving fundamental process descriptions. The morphology and vegetation’s role in determining water partitioning process has been epitomized in four parameters of the conceptual model. Numerical simulations explored a large set of basins in the five climates. Results show that climate superimposes partitioning rules for a given basin; morphological and vegetation watershed properties, as conceptualized by model parameters, determine the Fu’s parameter within a given climate. A sensitive analysis confirmed that vegetation has the most influencing role in determining water partitioning rules, followed by soil permeability. Finally, linear regressions relating basin characteristics to Fu’s parameter have been obtained in the five climates and tested in a basin for each case, obtaining encouraging results. The small amount of data required and the very low computational effort of the method make this approach ideal for practitioners and hydrologists involved in annual runoff assessment.

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Calibration and validation of SWAT model and estimation of water balance components of Shaya mountainous watershed, Southeastern Ethiopia

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-10-13955-2013 ◽

2013 ◽

Vol 10 (11) ◽

pp. 13955-13978 ◽

Cited By ~ 21

Author(s):

A. A. Shawul ◽

T. Alamirew ◽

M. O. Dinka

Keyword(s):

Best Management Practices ◽

Management Practices ◽

Assessment Tool ◽

Swat Model ◽

Watershed Modeling ◽

Coefficient Of Determination ◽

Water Yield ◽

Time Step ◽

Monthly Streamflow ◽

Mountainous Watershed

Abstract. To utilize water resources in a sustainable manner, it is necessary to understand the quantity and quality in space and time. This study was initiated to evaluate the performance and applicability of the physically based Soil and Water Assessment Tool (SWAT) model in analyzing the influence of hydrologic parameters on the streamflow variability and estimation of monthly and seasonal water yield at the outlet of Shaya mountainous watershed. The calibrated SWAT model performed well for simulation of monthly streamflow. Statistical model performance measures, coefficient of determination (r2) of 0.71, the Nash–Sutcliffe simulation efficiency (ENS) of 0.71 and percent difference (D) of 3.69, for calibration and 0.76, 0.75 and 3.30, respectively for validation, indicated good performance of the model simulation on monthly time step. Mean monthly and annual water yield simulated with the calibrated model were found to be 25.8 mm and 309.0 mm, respectively. Overall, the model demonstrated good performance in capturing the patterns and trend of the observed flow series, which confirmed the appropriateness of the model for future scenario simulation. Therefore, SWAT model can be taken as a potential tool for simulation of the hydrology of unguaged watershed in mountainous areas, which behave hydro-meteorologically similar with Shaya watershed. Future studies on Shaya watershed modeling should address the issues related to water quality and evaluate best management practices.

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HYDROLOGIC BEHAVIOUR OF HIGHLAND CATCHMENT IN HUMID TROPICAL REGION USING QSWAT MODEL

June-2020 - International Journal of Engineering Sciences & Research Technology ◽

10.29121/ijesrt.v9.i6.2020.16 ◽

2020 ◽

Vol 9 (6) ◽

pp. 95-103

Keyword(s):

Water Resources ◽

Water Balance ◽

River Basin ◽

Assessment Tool ◽

Annual Rainfall ◽

Tropical Region ◽

Water Balance Components ◽

Monthly Streamflow ◽

Average Annual Rainfall ◽

Tropical Watersheds

Water resources planning and management of a region requires an understanding of the water balance in the region. The Soil and Water Assessment Tool (SWAT) with QGIS interface (QSWAT) has been used here to arrive at the water balance components in the Palapuzha watershed of Valapattanam river basin in Kerala. Valapattanam river drains an area of 1867 sq.km. with 456 sq.km. area in Karnataka State. The river basin receives an average annual rainfall of 3600 mm. The Palapuzha watershed drains an area of 237.25 sq.km with an average annual rainfall of 4562 mm. The QSWAT model has been calibrated and validated using data for a period of eight years (2000-2007) for which both rainfall and streamflow data are available. The model was successful in simulating monthly streamflow during the calibration and validation periods with Nash Sutcliffe efficiency and correlation co-efficient greater than 0.75 and percent bias less than 10%, showing that the model is very good for predicting streamflow in Valapattanam river basin. This calibrated model was used to arrive at the different water balance components in the Palapuzha watershed. The results obtained will be useful for the sustainable development and planning of the water resources system in the highland humid tropical watersheds

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Simulated Longleaf Pine (Pinus palustris Mill.) Restoration Increased Streamflow – a Case Study in the Lower Flint River Basin

10.22541/au.162143457.79306110/v1 ◽

2021 ◽

Author(s):

Ji Qi ◽

Steven Brantley ◽

Stephen Golladay

Keyword(s):

River Basin ◽

Water Scarcity ◽

Assessment Tool ◽

Longleaf Pine ◽

Pinus Palustris ◽

Potential Effect ◽

Low Flow ◽

Water Yield ◽

Monthly Streamflow ◽

Flint River

Water scarcity in the southeastern United States has increased in recent decades due to population growth, land use intensification, and climate variability. Precipitation is relatively abundant, but declines in streamflow suggest a need to better manage water yield. Restoration of low-density, frequent-fire longleaf pine (Pinus palustris Mill.) woodlands, which once dominated the southeastern Coastal Plain, represents a possible strategy to increase water yield and mitigate water scarcity. The Flint River Basin has seen recent conflicts over water appropriations and lies within the historic range of longleaf pine. We used the Soil and Water Assessment Tool (SWAT) to evaluate the potential effect of longleaf pine restoration on streamflow in the Ichawaynochaway Creek, a major tributary of the Flint River. Parameters governing plant water use, e.g. leaf area and leaf physiology, were adjusted to create a longleaf pine land cover. We simulated the conversion of ~95,000 ha of existing forest to longleaf pine, an increase from 3% to 35% of landcover in the basin. Modeled evapotranspiration was lower for longleaf pine compared to other forest types in the region, and conversion to longleaf pine increased annual water yield by 17.9 ± 1.6 mm, or 5.2%. Proportional changes in monthly streamflow were up to 74% higher during low flow periods, when in-stream habitat is most vulnerable. Restoration of longleaf pine could be a promising way to mitigate water scarcity in the southeastern U.S., and adding flow during extreme droughts may prove vitally important for conserving imperiled aquatic organisms.

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Effectiveness of Contour Farming and Filter Strips on Ecosystem Services

Water ◽

10.3390/w10101312 ◽

2018 ◽

Vol 10 (10) ◽

pp. 1312 ◽

Cited By ~ 3

Author(s):

John Gathagu ◽

Khaldoon Mourad ◽

Joseph Sang

Keyword(s):

Ecosystem Services ◽

Sediment Yield ◽

Water Conservation ◽

Assessment Tool ◽

Water Yield ◽

Model Parameters ◽

Subsequent Increase ◽

Filter Strips ◽

Filter Width ◽

Annual Sediment

The failing ecosystem services in Thika-Chania catchment is manifested in the deterioration of water quality, sedimentation of reservoirs, and subsequent increase in water treatment costs due to high turbidity. The services can be restored by implementing relevant soil and water conservation practices to enhance flow regulation and control sediment yield. The impacts of contour farming and filter strips on water and sediment yield were evaluated using Soil Water and Assessment Tool (SWAT), Texas A&M University, USA. Sediment calibration and validation was achieved using data obtained from a bathymetric survey. Model parameters were adjusted to simulate the conservation impacts of contour farming and filter strips. Results indicated the average annual sediment yield as 22 t/ha at the outlet of the catchment and average annual surface runoff of 202 mm. The simulation results showed that filter strips of 5 m width would reduce the average annual sediment yield from the catchment by 54%. The efficacy of filter strips in reducing sediment yield was observed to increase with increasing filter width. Three-meter filter strips and contour farming reduced the average annual sediment yield at catchment outlet by 46% and 36%, respectively. It was concluded that the implementation of contour farming and filters strips reduced sediments by 63% from the base value. Water yield at the sub-basin level was only influenced by contour farming. The total water yield at the catchment outlet experienced no significant change.

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Hydrologic Responses to Climate Variability and Human Activities in Lake Ziway Basin, Ethiopia

Water ◽

10.3390/w12010164 ◽

2020 ◽

Vol 12 (1) ◽

pp. 164 ◽

Cited By ~ 1

Author(s):

Mulugeta Musie ◽

Sumit Sen ◽

Indrajeet Chaubey

Keyword(s):

Land Use ◽

Land Use Change ◽

Climate Variability ◽

Human Activities ◽

Surface Runoff ◽

Assessment Tool ◽

Water Yield ◽

Monthly Streamflow ◽

Annual Water ◽

Hydrologic Responses

Hydrological impacts of human activities and climate variability on Ketar and Meki watersheds of Lake Ziway basin, Ethiopia were studied using the soil and water assessment tool. Three land-use change and two climate variability scenarios were considered to analyze the separate and combined impacts on annual water balance, monthly streamflow, and spatial distributions of evapotranspiration and water yield. The evaluation showed that changes in land use resulted in an increase in annual surface runoff and water yield for Ketar watershed and an increase in annual ET for Meki. Similarly, the climate variability resulted in a decrease in annual ET, surface runoff, and water yield for Ketar watershed and a decrease in ET for Meki. Overall, climate variability has greater impacts on the monthly streamflow compared to land-use change impacts. Similarly, greater sensitivity in hydrologic response was observed for Ketar watershed compared to Meki watershed.

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Evaluation and Prediction of the Impacts of Land Cover Changes on Hydrological Processes in Data Constrained Southern Slopes of Kilimanjaro, Tanzania

Earth ◽

10.3390/earth2020014 ◽

2021 ◽

Vol 2 (2) ◽

pp. 225-247

Author(s):

Mateso Said ◽

Canute Hyandye ◽

Ibrahimu Chikira Mjemah ◽

Hans Charles Komakech ◽

Linus Kasian Munishi

Keyword(s):

Land Cover ◽

Water Balance ◽

Surface Runoff ◽

Agricultural Land ◽

Assessment Tool ◽

Swat Model ◽

Water Yield ◽

Land Cover Changes ◽

Least Squares Regression ◽

Water Balance Components

This study provides a detailed assessment of land cover (LC) changes on the water balance components on data constrained Kikafu-Weruweru-Karanga (KWK) watershed, using the integrated approaches of hydrologic modeling and partial least squares regression (PLSR). The soil and water assessment tool (SWAT) model was validated and used to simulate hydrologic responses of water balance components response to changes in LC in spatial and temporal scale. PLSR was further used to assess the influence of individual LC classes on hydrologic components. PLSR results revealed that expansion in cultivation land and built-up area are the main attributes in the changes in water yield, surface runoff, evapotranspiration (ET), and groundwater flow. The study findings suggest that improving the vegetation cover on the hillside and abandoned land area could help to reduce the direct surface runoff in the KWK watershed, thus, reducing flooding recurring in the area, and that with the ongoing expansion in agricultural land and built-up areas, there will be profound negative impacts in the water balance of the watershed in the near future (2030). This study provides a forecast of the future hydrological parameters in the study area based on changes in land cover if the current land cover changes go unattended. This study provides useful information for the advancement of our policies and practices essential for sustainable water management planning.

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