Evaluation and Zoning of Agricultural Water Demand Supply Ratio Index (AGWS) using SWAT (Case Study: Gunbarchay basin)

Document Type : Research Paper


1 Department of Water Engineering, Faculty of Agriculture, University of Tabriz, Tabriz,Iran

2 Department of Water Engineering, Faculty of Agriculture, University of Tabriz, Tabriz City, Iran

3 Associate Professor, Department of Water Engineering, Tabriz University, Tabriz, Iran


The agricultural water demand supply ratio (AGWS) is the actual evapotranspiration ratio to the potential evapotranspiration in an agricultural area during the crop growth period. Determination of this ratio is very important to planning and management properly in an area. In this regard, the index and its zoning in the agricultural areas of Gunbarchay basin were determined in this study. To achieve this purpose, the comprehensive SWAT hydrological-plant model for the basin was adjusted, calibrated and validated. Then, the actual runoff and evapotranspiration values were simulated for the sub-basins of the studied basin during the period 1987-2017. The results indicated that the volume of potential evapotranspiration, in all irrigated lands of the basin during the crop growth period in 2016 is 25.41 MCM. In addition, the simulations showed that the amount of actual evapotranspiration from the total irrigated agricultural lands of Gunbarchay basin during the crop growing season in 2016 is 19.1 MCM. Based on the results, the value of agricultural water supply ratio in Gunbarchay basin in 2016 varies between 0.63 and 0.79. So that the value of this index is more in the northern and western sub-basins of the basin than its eastern sub-basins. According to the results, in Gunbarchay basin, the amount of water supply in the agricultural sector is much less than the amount of demand, especially in the eastern sub-basins, which should be addressed with proper management of agricultural water demand and consumption.


Abbaspour K.C. (2008). SWAT-CUP2: SWAT Calibration and Uncertainty Programs -A User Manual. Department of Systems Analysis, Integrated Assessment and Modelling (SIAM), Eawag, Swiss Federal Institute of Aquatic Science and Technology, Duebendorf, Switzerland, 95 pp.
Alizadeh, A. and Kamali, Q. (2007). Water needs of plants in Iran, Imam Reza University Press. (In Farsi)
Arnold, J.G. and Fohrer, N. (2005). SWAT 2000: Current capabilities and research opportunities in applied watershed modeling. Hydrol. Process., 19(3): 563‐572.
Arnold, J.G., Muttiah, R.S., Srinivasan, R. and Allen, P.M. (2000). Regional estimation of base flow and groundwater recharge in the Upper Mississippi River basin. J. Hydrol., 227: 1-4. 21-40.
Arnold, J.G., Srinivasan, P., Muttiah, R.S. and Williams, J.R. (1998). Large area hydrologic modeling and assessment. Part I. Model development. Journal of the American Water Resources Association, 34: 73–89
Dastoorani, M., Poormohammadi, S. and Rahimian, M.H. (2012). Estimation of Actual Evapotranspiration in Ardakan Pistachio Orchards Using Remote Sensing. Journal of Water Research in Agriculture, 26(1): 1-13. (In Farsi)
Green, C.H. and Griensven, A.V. (2008). Autocalibration in hydrologic modeling: using SWAT 2005 in small-scale  watersheds. Environmental Modeling and Software, 23: 422–434.
Husain, M.Kh., Hayder, G., Sidek, L.M., Ahmed, A.N. and Kushiar, Kh.F. (2019). Potential Evapotranspiration Estimation Methods for Water Balance Analysis Using SWAT: A Case Study of Kelantan River Basin, Kelantan. International Conference on Dam Safety Management and Engineering, ICDSME 2019: ICDSME 2019 pp 90-102.
Jeimar P.P., Marcela Q. and Natalia E. (2011). Application of crop growth modeling for the economic valuation of water in agriculture. The 3rd international forum on water and food Tshwane, South Africa.
Kang, M.S., Park, S.W., Lee, J.J. and Yoo, K.H. (2006). Applying SWAT for TMDL programs to a small watershed containingrice paddy fields. Agricultural Water Management, 79: 72–92.
Kaushal K., Luna B., Anju G., Biju G., Sreedhar A., Kiran J. and Narasimhan B. (2011). Spatial mapping of agricultural water productivity using SWAT model in Upper Bhima Catchment, India. Irrigation and Drainage, DOI: 10.1002/ird.618.
Lakshmanan, A., Geethalakshmi, V., Srinivasan, R., Nagothu, U.S. and Annamalai, H. (2011). Climate change adaptation strategies in Bhavani basin using SWAT model. Applied Eng. in Agric., 27(6): 887-893.
Lirong, S. and Jianyun, Z. (2012). Hydrological Response to Climate Change in Beijiang River        Basin Based on the SWAT Model. Procedia Engineering, 28: 241 – 245.
Luo, Y., He, C., Sophocleous, M., Yin, Z., Hongrui, R. and Ouyang, Z. (2008). Assessment of crop growth and    soil water modules in SWAT 2000 using extensive field experiment data in an irrigation district of the Yellow River Basin. Journal of Hydrology, 352: 139–156.
Immerzeel, W., Gaur, A. and Zwart, S. (2008). Integrating remote sensing and a process-based hydrological model to evaluate water use and productivity in a south Indian catchment. Agricultural water management, 95: 11-24.
Jabbari, A., Hoseini, M. and Khosrojerdi, A. (2012). Evaluation of sensitivity of flow parameters in Sanjabi basin using SWAT model. Third national conference on comprehensive water resources management. University of agricultural sciences and natural resources of Sari. (In Farsi)
Moghaddasi, M., Morid, S. and Delavar, M. (2015) Urmia agricultural water consumption management approach in Urmia Lake restoration. Iran-Water Resources Research, 11:1-12. (In Farsi)
Neitsch, S.L., Arnold, J.G., Kiniry, J.R. and Williams, J.R. (2011). Soil and water assessment tool theoretical document (version 2009), Texas water resource institute technical report.
Panhalkar, S.S. (2014). Hydrological modeling using SWAT model and geoinformatic techniques,The Egyptian Journal of Remote Sensing and Space Sciences, 17(2): 197-207.
Schuol, J., Abbaspour, K.C., Srinivasan, R. and Yang, H. (2008). Estimation of freshwater availability in the West African sub-continent using the SWAT hydrologic model. Journal of  Hydrology, 352: 30–49.
Tajrishi, (2017). Interview with Iran Newspaper. www.iran-ewspaper.com/Newspaper/ BlockPrint/ 144763, Plan for reviving Iranian wetlands, (2012). Urmia Lake Drought Risk Management Program,https://www.doe.ir/portal/theme/talab/Data/021-DRM.html .(In Farsi)