覆膜集雨补灌对冬小麦产量和水分利用效率的影响

Effects of plastic-film mulching and supplementary irrigation on yield and water use efficiency of winter wheat

为确定半湿润易旱区垄沟集雨种植模式下冬小麦拔节期的适宜补灌量及探究不同地膜对土壤蓄水保墒和节水增产效果的差异,设置垄上覆普通地膜(P)和生物降解膜(J)2种处理,并结合雨养(I0)、拔节期补灌20mm(I1),40mm(I2),60mm(I3),对比分析不同地膜不同补灌量下0~200cm土层土壤贮水量、冬小麦产量和水分利用效率的变化.结果表明:覆膜可显著提高0~100cm土壤贮水量,处理J在苗期保墒性与P相当,之后显著低于处理P;覆膜使苗期后100~200cm土壤贮水量显著低于CK,但P,J间差异不具有统计学意义.补灌能显著增加0~200cm土壤贮水量,处理I3的土壤贮水量最高,I2次之.覆膜处理的产量和水分利用效率均显著大于CK,P略大于J,但差异不具有统计学意义.2种不同膜覆盖下处理I2的平均籽粒产量比处理I3低1.50%,但处理I2的平均水分利用效率与灌溉水利用效率较I3分别提高2.4%和37.5%.因此,垄覆生物降解膜,沟内种植,结合冬小麦拔节期补灌40mm(I2)是缓解残膜污染、增产节水的最优处理.

Field experiment was conducted to determine the appropriate supplemental irrigation amount of winter wheat at the jointing stage with the ridge and furrow rain harvesting cultivation and explore the difference of the film mulching on soil water conservation and water-saving effects in semihumid and drought prone areas.The ridges covered with plastic film(P)and biodegradable film(J),combined with rain-fed(I 0),supplementary irrigation 20 mm(I1),40 mm(I2),60 mm(I3)at the jointing stage were set up to analyze and compare soil water storage,winter wheat yield and water use efficiency(WUE)changes under different supplemental irrigation amounts and mulching patterns at 0-200 cm soil depths.The results show that the film mulching can significantly improve the soil water storage of 0-100 cm,the effect of conserving soil moisture of J is similar to that of P at the seedling stage and lower than that of P after the seedling stage.Soil water storage of the film mulching is significantly lower than that of CK at 100-200 cm after the seedling period,but there is no significant difference between P and J.The irrigation measures can significantly increase the soil water storage of 0-200 cm,and the soil water storages in I3 and I2 are the highests and second highest,respectively.The winter wheat yield and WUE of the film mulching are obviously higher than those of CK,while the winter wheat yield and WUE of P are slightly higher than those of J,but there is no significant difference.The average grain yield of I2 is 1.50%lower than that of I3 under two different film coverings.But the ave-rage WUE and irrigation WUE of I2 are the highest.Compared with I3,the average WUE and irrigation WUE of I2 are improved by 2.4%and 37.5%,respectively.Therefore,the ridge with biodegradable film,furrow planting,combined with I2 is the best treatment of alleviating residual film pollution,water saving and high yield.