Simulating seepage from branch canal under crop, land and water relationships
2009
Arshad, M. (University of Agriculture, Faisalabad (Pakistan). Dept. of Irrigation and Drainage) | Ahmad, N. (University of Agriculture, Faisalabad (Pakistan). Dept. of Irrigation and Drainage) | Usman, M. (University of Agriculture, Faisalabad (Pakistan). Water Management Research Centre)
The rapid growth of tubewells in the Indus Basin of Pakistan shows significant contribution of groundwater in the irrigated agriculture development. The dependence on groundwater has increased due to rapid growth in cropping intensity and increasing water demand. Hence, to support a long-term agricultural management the sustainability of groundwater largely depends on seepage from canals. This paper presents model simulation assessments of the time dependent seepage to groundwater under the crop, land and water scenarios, as a case study for a branch canal system in Punjab, Pakistan. Assessment of seepage from canal was performed using a surface-groundwater model, MODFLOW. Model calibrations were performed to obtain close agreement between the observed and simulated water levels over one year study period. The monthly average seepage rate from the canal was assessed as 12.10 m3/s/million-m2 for a monthly average flow rate of 106 m3/s. Resultan tly the contribution of seepage to groundwater is based on the water balance components including recharge flow, applied irrigation, rainfall, lateral flow and evapotranspiration from the existing cropping system. A relationship between seepage (S) and the canal flow rate (Q) was developed (S = 0.006 Q1.44) to quantify the seepage to groundwater from the canal for any flow rate.
Показать больше [+] Меньше [-]Ключевые слова АГРОВОК
Библиографическая информация
Эту запись предоставил National Agricultural Research Centre