Study of the Effect Super absorbent A200 on the Pattern of Water Flow in Furrow Irrigation

Agriculture is the largest consumer of water resources in Iran. One of the best options for increasing the irrigation efficiency and better application of precipitation in arid and semi-arid areas is employing superabsorbent polymers to soil. Polymers can absorb rain and irrigation water, decrease deep percolation and increase water use efficiency. In this research we examined the effect of super absorbent on the pattern of water (advance and rollback curve) and calculating the parameters of advance and rollback equation in furrow irrigation based on the existing relationships and also examined the accuracy of these relations in comparison with the real data. The experiment were performed in the educational farm of the Gorgan university of Natural Resources and Agriculture in a no cultivation conditions. In this research four combinations of superabsorbent polymers A200 with soil which were composed of 0, 7, 11, 16, gram of polymers in square at a depth of 25 cm and the electric current of 0.75 liter per second were considered. The experiment was performed four times. The results indicated that by adding polymers to the soil, advance and rollback time were increased. Elliott and Walker equations advance and rollback calculations are accurate enough. A according to the advance curves, in the control furrow, water advance at outset is fast but gradually was reduced to the end of furrow, with increasing polymer advance speed the water movement fluctuations to the end end furrow is less variable. Also these changes were observed in the rollback curve.