عنوان مقاله [English]
نویسندگان [English]چکیده [English]
For sustainable use as well as vulnerability assessment of aquifers, an estimation of the groundwater recharge is indispensable. In Iran, located in a semi-arid region, the groundwater recharge is closely related to and dependent on the return flow from irrigation. Therefore, an assessment of the proportion of the return flow, as recharge, from different irrigation methods is essential for better understanding and management of groundwater resources. Throughout the present study in Neyshabour watershed, the level of groundwater resulted from two different irrigation methods (furrow and sprinkler irrigation) were estimated using soil moisture measurement in two 6 meter depth wells on a wheat farm. In each well, REC sensors were installed within 0.5 meter intervals and two sensors installed at 0.15 and 0.3 m depths. Through the sensors, the soil moisture was daily measured for duration of 173 days. The collected data were used to simulate the unsaturated flow within these points using the 1D HYDRUS package. The model in each point was calibrated and implemented to estimate the drainage level underneath the 6 meter depth of soil layer. The application level of irrigation water, in furrow irrigation, was about 230 mm while it was 299 mm for sprinkler type of irrigation. The drainage level from 6 meter soil layer during the 173 days, in for furrow irrigation was 80 mm while in the sprinkle case it was negligible.