Hydrological modelling using SWAT in a Complex Semi-Arid Watershed
1 National Agronomic Institute of Tunisia - INAT, Carthage University, LR17AGR01 InteGRatEd Management of Natural Resources: remoTE Sensing, Spatial Analysis and Modeling (GREEN-TEAM), Tunis 1082, Tunisia.
2 Center for Water Research and Technologies - CERTE, LR15CERTE01, Georesources Laboratory, P.O. Box 273, Soliman 8020, Tunisia.
3 Higher School of Agriculture of Mograne – ESAM, University of Carthage, LR03AGR02 Research Laboratory of Agricultural Production Systems and Sustainable Development (SPADD), Zaghouan 1121, Tunisia.
Research Article
GSC Advanced Research and Reviews, 2024, 21(02), 238-247.
Article DOI: 10.30574/gscarr.2024.21.2.0427
Publication history:
Received on 26 September 2024; revised on 07 November 2024; accepted on 09 November 2024
Abstract:
Hydrological models have emerged as essential tools for examining the hydrological processes of complex watersheds addressing various environmental and water resource issues. This study focuses on modeling the hydrology of the Merguellil watershed in central Tunisia using the Soil and Water Assessment Tool (SWAT). The SWAT model is a physical modeling tool developed to forecast hydrological processes and is well-documented as an effective tool for resource water management. The primary objective of this research is to evaluate the SWAT model's performance in simulating monthly hydrological processes within the Merguellil watershed in central semi-arid Tunisia. Calibration of the model was conducted from 2002 to 2011, followed by a validation from 2012 to 2017. Sensitivity analysis identified key parameters, including Curve Number, Slope Length, and effective hydraulic conductivity, as the most sensitive. The findings demonstrate that the model exhibits satisfactory performance according to goodness-of-fit criteria during both the calibration and validation phases. The Nash–Sutcliffe Efficiency (NSE) were 0.65 and 0.41, respectively, for calibration and validation periods. The coefficient of determination (R²) and Kling-Gupta efficiency (KGE) are both equal to 0.7, the RMSE-observations standard deviation ratio (RSR) is less than or equal to 0.6, for calibration. The Percent Bias (PBIAS) indicates that the model overestimates the discharges by +23.5% during the calibration period. In addition, the runoff in Merguellil watershed demonstrated a notable spatio-temporal variability, significantly influenced by the complexity and heterogeneity of its environment.
Keywords:
Hydrological modeling; Calibration; Runoff; SWAT model; Tunisia
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Copyright © 2024 Author(s) retain the copyright of this article. This article is published under the terms of the Creative Commons Attribution Liscense 4.0
