Assessing Variation of Runoff and Nitrate Concentration in Management Scenarios Using SWAT Model, (Case Study: Hashtgerd Plain)

Document Type : Research Paper


1 Department of civil Engineering,Science and Research Branch,Islamic Azad University

2 Department of Civil, Water and Environmental Engineering, Technical and Engineering Campus of Shahid Beheshti University, Tehran, Iran.

3 Department of Civil Engineering, Central Tehran Branch, Islamic Azad University, Tehran, Iran


Watershed management strategies can be considered in mitigating water pollution issues. In this study, using SWAT as a semi-distributive hydrological model, runoff and nitrate amounts have been investigated according to management scenarios in Hashtgerd plain, Iran. After runoff simulation, three hydrometric stations were used for calibration in the period (1990-2013) and validation in the period (2014-2018). The results of R2 and NS statistical indices (greater than 0.6) show that the simulation results in this catchment have been done with good accuracy. The results also indicate that applying the first scenario (changing the crop pattern) and the second scenario (increasing irrigation efficiency) reduced the water usage in the agricultural sector from 85.3 MCM to 59.8 MCM in the present condition, which also will improve the fertilizing efficiency. It was demonstrated that changing the crop pattern can help reduce the deep percolation. On the other hand, using drip irrigation, the leaching requirement, and irrigation water loss will be reduced. Comparing the amounts of observed nitrate in the hydrometric station in the base period with the simulation results in the first scenario revealed that, by applying the first scenario, the amount of nitrate simulated has relatively a decreasing trend except in winter and early spring. The results of the second scenario show that by changing the irrigation method, the amount of nitrate leaching has decreased significantly compared to the base period. In general, the second scenario is more effective in reducing nitrate leaching and is recommended.


Abbasi, H., Delavar, M., Bigdeli, R., (2017) Defining optimum pattern for irrigation manegemnt in agricaultural section using optimization-simulation approach by SWAT model, 16th Iranian Hydraulic Conference, Ardabil, University of Mohaghegh Ardabili. (In Farsi)
Abbaspour, K.C. (2013) SWAT-CUP 2012: SWAT Calibration and Uncertainty Programs - A User Manual, Swiss Federal Institute of Aquatic Science and Technology, Switzerland.
Gheysari, M., Mirlatifi S.M., Homaee M., Asadi M.A., (2006), Nitrate leaching in sprinkler irrigation system under the management of corn fertigation, Agricultural Engineering Research journal, 29(7):101-118
Abbaspour, K.C., J. Yang, I. Maximov, R. Siber K. Bogner, J. Mieleitner, J. Zobrist and R. Srinivasan. (2007) Modelling hydrology and water quality in the pre- alpine/alpine Thur watershed using SWAT. Journal of Hydrology. 3332-4:413-430.
Arnold, J.G., Srinivasan, R., Muttiah, R.S. and Williams, J.R., (1998) Large area hydrologic modeling and assessment part I: model development 1. JAWRA Journal of the American Water Resources Association, 34(1), pp.73-89.
Bagheri, R.M., Ghaemi, Z., Khajehzadeh, A., (2018) SWAT application in defining Nitrogen and Phosphor load in Seymareh Dam reservoir subbasin, 1st Conference on SWAT application in Water Resources Management, Esfahan, Esfahan Technical University. (In Farsi)
Bailey, R.T., Wible, T.C., Arabi, M., Records, R.M. and Ditty, J., (2016) Assessing regional scale spatio-temporal patterns of groundwater–surface water interactions using a coupled SWAT-MODFLOW model. Hydrological processes, 30(23), pp.4420-4433.
Biareh, M., Hoseini, A., (2016) Simulation of water quality for Karaj dam basin using SWAT model, 11st National Seminar on Watershed Management Science and Engineering, Yasooj University. (In Farsi)
Batoukhteh, F., Misaghi, F. and Dehghanisanji, H., (2017) The evaluation of effect of increase irrigation efficiency along with increased acreage on the return water and underground water storage using SWAT model,  Journal of Soil and Water Resources Conservation, 6(2), 1-13 (In Farsi)
Engebretsen, A., Vogt, R.D. and Bechmann, M., (2019) SWAT model uncertainties and cumulative probability for decreased phosphorus loading by agricultural Best Management Practices. Catena, 175, pp.154-166.
Ficklin, D.L., Luo, Y. and Zhang, M., (2013) Watershed modelling of hydrology and water quality in the Sacramento River watershed, California. Hydrological processes, 27(2), pp.236-250.
Imani, S., Delavar, M. and Niksokhan, M.H., (2017) Simulation and assessment of management practices for reduction of nutrients discharge to the Zrebar Lake using SWAT model.    Iran-Water Resources Research, 13(1), 69-87. (In Farsi)
Meshesha, W., Wang , J., Demelash, N. and Mclain, C., (2020), Groundwater Modelling Quality in the Cold Region of the Athabasca River BasinTesfa, journal of atmospheric science, doi: 10.20944/preprints202011.0299.v1.
Qiu, Z. and Wang, L., (2014) Hydrological and water quality assessment in a suburban watershed with mixed land uses using the SWAT model. Journal of Hydrologic Engineering, 19(4), pp.816-827.
Russo, M., (1991) Effects of fertilizer rate, application timing and plant spacing on yield and nutrient content of bell pepper, Journal of Plant Nutrition,,1016/j.jhydrol.201.126304
Shafiei, K., Porhemmat, J., Sedghi, H. and Hosseni, M., (2018) Investigation the effect of land use changes on the quantity of water resources using remote sensing data and SWAT model (Case study: Maroon basin-southwest of Iran). Journal of Soil and Water Resources Conservation, 7(3), 71-87. (In Farsi)
Shultz, C.D., Gates, T.K. and Bailey, R.T., (2018) Evaluating best management practices to lower selenium and nitrate in groundwater and streams in an irrigated river valley using a calibrated fate and reactive transport model. Journal of hydrology, 566, pp.299-312.
Wei, X. and Bailey, R., (2021) Evaluating nitrate and phosphorus remediation in intensively irrigated stream-aquifer systems using a coupled flow and reactive transport model. Journal of Hydrology, 598, 126-304.