黄河下游引黄灌区夏玉米需水规律与适宜灌溉定额研究OA

To scientifically determine the water demand and appropriate irrigation quota of maize in the Lower Yellow River diversion irriga-tion area,a controlled irrigation experiment was conducted using test pits with eight different irrigation amounts.The water balance method was employed to calculate maize water demand,and the effects of different irrigation treatments on maize water consumption characteristics,yield,and water use efficiency were analyzed.A water production function was constructed and the optimal irrigation quota was solved.The results showed that:The daily water consumption intensity of maize throughout the growing period generally exhibited a low-high-low trend.The water consumption modulus was the largest during the jointing-tasseling stage,ranging from 40.48%to 48.95%.Both yield and water use efficiency first increased and then decreased with the increase of irrigation quota.Maize yield reached its maximum of 11 903.25 kg/hm2 at an irrigation quota of 400 mm,while water use efficiency peaked at 2.76 kg/m3 at an irrigation quota of 320 mm.A significant linear positive correlation was observed between maize evapotranspiration and irrigation quota,with a correlation coefficient exceeding 0.96.Considering both yield and water use efficiency,the appropriate surface irrigation quota for maize in the Weishan irrigation area was determined to be 438 mm.After deducting effective rainfall,the supplementary irrigation quota was 124.12 mm,which converted to a supplementary irrigation quo-ta of 150.45 mm at the outlet of the lateral canal.This value is close to the latest agricultural water quota standard of Shandong Province.