华北平原秸秆覆盖滴灌冬小麦中后期耗水规律研究

Research on the water consumption rule of winter wheat in middle and late stage by drip irrigation with straw-mulching in North China Plain

基于2013—2015年华北平原典型区连续两年田间试验,采用Penman-Monteith公式、FAO单作物系数法以及水量平衡法,研究分析了充分滴灌下秸秆覆盖与不覆盖对冬小麦棵间蒸发、耗水量、产量及水分利用效率的影响,研究结果表明:滴灌条件下秸秆覆盖显著抑制了日棵间蒸发量及其日变化波动幅度(P<0.05),在冬小麦中后期相比不覆盖可减少棵间蒸发30%以上;基于田间冬小麦的气孔阻力系数实测值,采用P-M公式直接计算冬小麦日耗水量具有较高精度,其值与FAO单作物系数法计算值具有较高相关性(R^2>0.8);秸秆覆盖滴灌减少了7%~15%的灌溉定额,但与不覆盖滴灌相比,冬小麦日耗水量和生育期总耗水量不存在显著差异(P>0.05),冬小麦4—6月份期间平均日耗水量在4.0~4.5 mm·d^(-1)之间;充分滴灌下秸秆覆盖并没有显著提高作物的产量和水分利用效率(P>0.05)。

Based on the field experiments of two consecutive years( 2013—2015) in North China Plain( NCP),using the Penman-Monteith Equation( P-M),FAO single crop coefficient method and water balance method,We researched and analyzed the influences of straw mulching and without mulching to the soil evaporation,water consumption,yield and water use efficiency( WUE) of winter wheat under full drip irrigation. The research results indicated that: The straw mulching under drip irrigation could notably restrained the daily soil evaporation and its fluctuation range( P<0.05) compared with no mulching,the daily evaporation could be reduced more than30% in middle and late period of winter wheat. Based on the field measured stomatal resistance coefficient of winter wheat,using the P-M formula to directly calculate the daily water consumption of winter wheat has possessed good accuracy. It has a high correlation with the calculated value by FAO single crop coefficient method( R^2> 0. 8).Though the irrigation norm could be decreased about 7% ~ 15% by straw mulching with drip irrigation,compared with no mulching and drip irrigation,the daily water consumption and total water consumption during growth period did not existed significant difference. The daily water consumption of winter wheat was between 4.0 mm·d^(-1) to 4.5 mm·d^(-1) during April to June. The crop yield and WUE were not significantly increased under full drip irrigation with straw mulching( P>0.05).