Development and application of a physically based landscape water balance in the SWAT model

Watershed models are used worldwide to assist with water and nutrient management under conditions of changing climate, land use, and population. Of these models, the Soil and Water Assessment Tool (SWAT) and SWAT+ are the most widely used, although their performance in groundwater-driven watersheds can sometimes be poor due to a simplistic representation of groundwater processes. The purpose of this paper is to introduce a new physically-based spatially-distributed groundwater flow module called gwflow for the SWAT+ watershed model. The module is embedded in the SWAT+ modeling code and is intended to replace the current SWAT+ aquifer module. The model accounts for recharge from SWAT+ Hydrologic Response Units (HRUs), lateral flow within the aquifer, Evapotranspiration (ET) from shallow groundwater, groundwater pumping, groundwater–surface water interactions through the streambed, and saturation excess flow. Groundwater head and groundwater storage are solved throughout the watershed domain using a water balance equation for each grid cell. The modified SWAT+ modeling code is applied to the Little River Experimental Watershed (LREW) (327 km2) in southern Georgia, USA for demonstration purposes. Using the gwflow module for the LREW increased run-time by 20% compared to the original SWAT+ modeling code. Results from an uncalibrated model are compared against streamflow discharge and groundwater head time series. Although further calibration is required if the LREW model is to be used for scenario analysis, results highlight the capabilities of the new SWAT+ code to simulate both land surface and subsurface hydrological processes and represent the watershed-wide water balance. Using the modified SWAT+ model can provide physically realistic groundwater flow gradients, fluxes, and interactions with streams for modeling studies that assess water supply and conservation practices. This paper also serves as a tutorial on modeling groundwater flow for general watershed modelers.

Download Full-text

The environmental effects of global changes on northeast central Europe in the case of non-modified agricultural management

Landscape Online ◽

10.3097/lo.200804 ◽

2008 ◽

Vol 4 ◽

pp. 1-17 ◽

Cited By ~ 4

Author(s):

Hubert Wiggering ◽

Frank Eulenstein ◽

Wilfried Mirschel ◽

Matthias Willms ◽

Claus Dalchow ◽

...

Keyword(s):

Water Balance ◽

Agricultural Production ◽

Nutrient Dynamics ◽

Climate Scenario ◽

Climate Impact ◽

Global Changes ◽

Land Use Types ◽

Landscape Water ◽

Well Data ◽

Landscape Water Balance

Climate impact scenarios for agriculture usually consider yield development, landscape water balance, nutrient dynamics or the endangerment of habitats separately. Scenario results are further limited by roughly discriminated land use types at low spatial resolution or they are restricted to single sites and isolated crops. Here, we exemplify a well data based comprehensive sensitivity analysis of a drought endangered agrarian region in Northeast Germany using a 2050 climate scenario. Coherently modelled results on water balance and yields indicate that agricultural production may persist, whereas wetlands and groundwater production will be negatively affected. The average percolation rate decreases from 143 mm a-1 to 12 mm a-1, and the average yield decline broken down by crops ranges from 4% for summer wheat to 14% for potatoes (main cereals: 5%).

Download Full-text

Assessing Climate Change Impact on Water Balance Components of Upper Baitarni River Basin using SWAT Model

Journal of Earth Science & Climatic Change ◽

10.4172/2157-7617.1000267 ◽

2015 ◽

Vol 06 (03) ◽

Author(s):

Bhumika Uniyal Madan Kumar Jha

Keyword(s):

Climate Change ◽

Water Balance ◽

River Basin ◽

Climate Change Impact ◽

Swat Model ◽

Water Balance Components ◽

Change Impact

Download Full-text

Comparative evaluation of conceptual and physical rainfall–runoff models

Applied Water Science ◽

10.1007/s13201-019-1122-6 ◽

2020 ◽

Vol 10 (1) ◽

Cited By ~ 6

Author(s):

R. K. Jaiswal ◽

Sohrat Ali ◽

Birendra Bharti

Keyword(s):

Water Balance ◽

Swat Model ◽

Water Balance Model ◽

Optimization Techniques ◽

Balance Model ◽

Series Data ◽

Climatic Data ◽

Rainfall Runoff ◽

Tank Model ◽

Australian Water

AbstractThe design of water resource structures needs long-term runoff data which is always a problem in developing countries due to the involvement of huge cost of operation and maintenance of gauge discharge sites. Hydrological modelling provides a solution to this problem by developing relationship between different hydrological processes. In the past, several models have been propagated to model runoff using simple empirical relationships between rainfall and runoff to complex physical model using spatially distributed information and time series data of climatic variables. In the present study, an attempt has been made to compare two conceptual models including TANK and Australian water balance model (AWBM) and a physically distributed but lumped on HRUs scale SWAT model for Tandula basin of Chhattisgarh (India). The daily data of reservoirs levels, evaporation, seepage and releases were used in a water balance model to compute runoff from the catchment for the period of 24 years from 1991 to 2014. The rainfall runoff library (RRL) tool was used to set up TANK model and AWBM using auto and genetic algorithm, respectively, and SWAT model with SWATCUP application using sequential uncertainty fitting as optimization techniques. Several tests for goodness of fit have been applied to compare the performance of conceptual and semi-distributed physical models. The analysis suggested that TANK model of RRL performed most appropriately among all the models applied in the analysis; however, SWAT model having spatial and climatic data can be used for impact assessment of change due to climate and land use in the basin.

Download Full-text

Impacts of deforestation on water balance components of a watershed on the Brazilian East Coast

Revista Brasileira de Ciência do Solo ◽

10.1590/s0100-06832014000400030 ◽

2014 ◽

Vol 38 (4) ◽

pp. 1350-1358 ◽

Cited By ~ 15

Author(s):

Donizete dos Reis Pereira ◽

André Quintão de Almeida ◽

Mauro Aparecido Martinez ◽

David Rafael Quintão Rosa

Keyword(s):

Water Balance ◽

Forest Cover ◽

East Coast ◽

Swat Model ◽

Native Forest ◽

Efficiency Coefficient ◽

Water Balance Components ◽

The Real ◽

Calibration And Validation ◽

Creek Watershed

The Brazilian East coast was intensely affected by deforestation, which drastically cut back the original biome. The possible impacts of this process on water resources are still unknown. The purpose of this study was an evaluation of the impacts of deforestation on the main water balance components of the Galo creek watershed, in the State of Espírito Santo, on the East coast of Brazil. Considering the real conditions of the watershed, the SWAT model was calibrated with data from 1997 to 2000 and validated for the period between 2001 and 2003. The calibration and validation processes were evaluated by the Nash-Sutcliffe efficiency coefficient and by the statistical parameters (determination coefficient, slope coefficient and F test) of the regression model adjusted for estimated and measured flow data. After calibration and validation of the model, new simulations were carried out for three different land use scenarios: a scenario in compliance with the law (C1), assuming the preservation of PPAs (permanent preservation areas); an optimistic scenario (C2), which considers the watershed to be almost entirely covered by native vegetation; and a pessimistic scenario (C3), in which the watershed would be almost entirely covered by pasture. The scenarios C1, C2 and C3 represent a soil cover of native forest of 76, 97 and 0 %, respectively. The results were compared with the simulation, considering the real scenario (C0) with 54 % forest cover. The Nash-Sutcliffe coefficients were 0.65 and 0.70 for calibration and validation, respectively, indicating satisfactory results in the flow simulation. A mean reduction of 10 % of the native forest cover would cause a mean annual increase of approximately 11.5 mm in total runoff at the watershed outlet. Reforestation would ensure minimum flows in the dry period and regulate the maximum flow of the main watercourse of the watershed.

Download Full-text

Regional Parameter Estimation of the SWAT Model: Methodology and Application to River Basins in the Peruvian Pacific Drainage

Water ◽

10.3390/w12113198 ◽

2020 ◽

Vol 12 (11) ◽

pp. 3198

Author(s):

Flavio Alexander Asurza-Véliz ◽

Waldo Sven Lavado-Casimiro

Keyword(s):

Water Balance ◽

Assessment Tool ◽

Hydrological Cycle ◽

Swat Model ◽

Parameters Estimation ◽

Data Availability ◽

Model Parameters ◽

Hydrological Data ◽

The Pacific ◽

Main Components

This study presents a methodology for the regional parameters estimation of the SWAT (Soil and Water Assessment Tool) model, with the objective of estimating daily flow series in the Pacific drainage under the context of limited hydrological data availability. This methodology has been designed to obtain the model parameters from a limited number of basins (14) to finally regionalize them to basins without hydrological data based on physical-climatic characteristics. In addition, the bootstrapping method was selected to estimate the uncertainty associated with the parameters set selection in the regionalization process. In general, the regionalized parameters reduce the initial underestimation which is reflected in a better quantification of daily flows, and improve the low flows performance. Furthermore, the results show that the SWAT model correctly represents the water balance and seasonality of the hydrological cycle main components. However, the model does not correctly quantify the high flows rates during wet periods. These findings provide supporting information for studies of water balance and water management on the Peruvian Pacific drainage. The approach and methods developed can be replicated in any other region of Peru.

Download Full-text

Pseudo-Spatially-Distributed Modeling of Water Balance Components in the Free State of Saxony

Hydrology ◽

10.3390/hydrology7040084 ◽

2020 ◽

Vol 7 (4) ◽

pp. 84

Author(s):

Thanh Thi Luong ◽

Judith Pöschmann ◽

Ivan Vorobevskii ◽

Stefan Wiemann ◽

Rico Kronenberg ◽

...

Keyword(s):

Water Balance ◽

Evaluation Model ◽

Free State ◽

Balance Model ◽

Mountain Range ◽

Water Balance Components ◽

Mean Values ◽

Physically Based ◽

Network Platform ◽

Available Information

Highly-resolved data on water balance components (such as runoff or storage) are crucial to improve water management, for example, in drought or flood situations. As regional observations of these components cannot be acquired adequately, a feasible solution is to apply water balance models. We developed an innovative approach using the physically-based lumped-parameter water balance model BROOK90 (R version) integrated into a sensor network platform to derive daily water budget components for catchments in the Free State of Saxony. The model is not calibrated, but rather uses available information on soil, land use, and precipitation only. We applied the hydro response units (HRUs) approach for 6175 small and medium-sized catchments. For the evaluation, model output was cross-evaluated in ten selected head catchments in a low mountain range in Saxony. The mean values of Kling–Gupta efficiency (KGE) for the period 2005–2019 to these catchments are 0.63 and 0.75, for daily and monthly discharge simulations, respectively. The simulated evapotranspiration and soil wetness are in good agreement with the SMAP_L4_GPH product in April 2015–2018. The study can be enhanced by using different data platforms as well as available information on study sites.

Download Full-text

A Physically Based Runoff Model Analysis of the Querétaro River Basin

Journal of Applied Mathematics ◽

10.1155/2014/586872 ◽

2014 ◽

Vol 2014 ◽

pp. 1-12 ◽

Cited By ~ 2

Author(s):

Carlos Javier Villa Alvarado ◽

Eladio Delgadillo-Ruiz ◽

Carlos Alberto Mastachi-Loza ◽

Enrique González-Sosa ◽

Ramos Salinas Norma Maricela

Keyword(s):

Land Use ◽

Water Balance ◽

River Basin ◽

Land Use Changes ◽

Geographical Location ◽

Physical Parameters ◽

Rainfall Runoff ◽

Strong Base ◽

Physically Based ◽

Runoff Model

Today the knowledge of physical parameters of a basin is essential to know adequately the rainfall-runoff process; it is well known that the specific characteristics of each basin such as temperature, geographical location, and elevation above sea level affect the maximum discharge and the basin time response. In this paper a physically based model has been applied, to analyze water balance by evaluating the volume rainfall-runoff using SHETRAN and hydrometric data measurements in 2003. The results have been compared with five ETp different methodologies in the Querétaro river basin in central Mexico. With these results the main effort of the authorities should be directed to better control of land-use changes and to working permanently in the analysis of the related parameters, which will have a similar behavior to changes currently being introduced and presented in observed values in this basin. This methodology can be a strong base for sustainable water management in a basin, the prognosis and effect of land-use changes, and availability of water and also can be used to determine application of known basin parameters, basically depending on land-use, land-use changes, and climatological database to determine the water balance in a basin.

Download Full-text