Water Accounting in Sugar Beet Farm under Duration and Depth water irrigation management (Case study: Meandoab region)

One of the main causes of drought occurrence in Urmia Lake in recent years was climate change and the development of crops with high water requirements including sugar beet. Water accounting is able to identify water saving opportunities by providing a clear picture of the amount of water used on the field. To this end, the water accounting and performance indicators based on the research results of the sugar beet fields in Miandoab region were extracted using the Aqua Crop model, and the accounting system was implemented based on low irrigation and irrigation duration in the framework of water accounting under field scale. According to the results, the contribution of precipitation from the net inflow in full irrigation with a seven-day rotation was about 8%, and with increased irrigation duration and imply of more low irrigation it amounted to 14%. An assessment of the drainage ratio from the gross inflow current showed that it was close to one in low irrigation interval and nearly all input water into the field was consumed (drained) and no opportunity was made to save water. Also, increase in irrigation duration resulted in an increase in the rate of evacuation of the total water consumption, which is considered as one of the objectives of water management in the field and improves the rate of evacuation process. Investigating the water use productivity indices showed that irrigation improved indices, but reduced the water use efficiency since in low irrigation, the rate of evaporation, which is a non-process loss, was significantly increased. Therefore, success in adopting a low irrigation strategy to save water involves the use of other management practices on the field such as the mulch and drip irrigation application which can control the evaporation.