基于土壤水分阈值下引黄灌区春玉米安全用水管理策略

A soil moisture threshold based management policy of safe water for spring maize in Yellow River Irrigation District

以内蒙古河套灌区隆胜试验区为研究区,开展引黄灌区玉米生育期适宜灌水量模拟研究。在田间试验的基础上,考虑土壤含水率、地下水埋深阈值,利用饱和带-非饱和带耦合模型SWAP-MODFLOW模拟了不同降雨水平年不同土壤质地区域玉米生育期灌溉用水量,预测了满足土壤水环境阈值的用水方案。基于耦合模型的决策结果：贫雨年安全用水量为269～315mm;平雨年165～225mm;丰雨年88～128mm。综上,利用实测资料检验后的耦合模型,结合不同作物的土壤水、地下水埋深阈值,能够更准确地从微观定量的角度确定不同作物最低灌水量,对河套灌区引黄水量的管理利用具有重要指导意义。

To make the farmland ecology environment in a healthy development status,we selected the Longsheng experimental area in Hetao Irrigation District as an object of the research.Then,a simulation research was applied to the Yellow River water irrigated areas which was intended for the farmland ecological security decision.On the basis of field experiment,the SWAP-MODFLOW coupling model of saturated zone-unsaturated zone was used to simulate the maize growth period of irrigation water consumption under different hydrological years and soil texture areas,by considering the soil moisture content and groundwater depth threshold.The water supply solutions met the threshold of soil water environment were predicted.The strategic results indicated that the water consumption in low precipitation year was 269 ～ 315 mm,the water consumption in normal year was165 ～ 225 mm,while high precipitation year was 88 ～ 128 mm.Summing up the above,the SWAP-MODFLOW coupling model which was examined with measured data could determine the minimum irrigation water for different crops precisely from the perspective of microscopic quantitative with the threshold of soil water and groundwater depth.It will be of great significance for the management and utilization of water demand from Yellow River in Hetao irrigation district.