不同灌溉方式和灌水量对土壤水盐及燕麦生长特征的影响

Effects of Different Irrigation Methods and Irrigation Amounts on Soil Water and Salt,and Oat Growth Characteristics

[目的]探究不同灌溉方式和灌水量对土壤水盐变化规律及燕麦生长特征的影响,为提高盐碱地作物的生产效能和土壤水分管理提供科学参考。[方法]采用盆栽试验,设置3种灌溉方式:常规灌溉、固定单侧灌溉(fixed unilateral root zone irrigation,FURI)、交替灌溉(alternative partial root zone irrigation,APRI),3组灌水量:W_1(60%θ_f~70%θ_f,θ_f为田间持水率),W_2(70%θ_f~80%θ_f)和W_3(80%θ_f~90%θ_f),以常规灌溉作为对照,共9组交互处理。[结果](1)不同灌溉方式下,土壤各层含水率变化趋势基本一致,随灌水量增加洗盐效果越显著,常规灌溉的深层含水率总体高于其他两种灌溉方式。(2)燕麦株高、叶绿素相对含量(relative chlorophyll content of leaves,SPAD)、品质随灌水量的增加而上升,与常规灌溉相比,W_2灌溉水平下,分根交替灌溉处理的粗脂肪,粗蛋白,β-葡聚糖含量分别增加7.02%,3.76%,6.06%,但降低了燕麦叶片的SPAD值,影响其光合能力。(3)随着燕麦生育期的推进,土壤盐分均呈现不同程度的累积,分根交替灌溉的积盐率最低,同时对燕麦根系生长、水分利用效率及产量影响显著,其中根系总长、根系总表面积、根系总体积较相同灌水量(W_2)的常规灌溉分别增加6.75%,6.92%,12.5%,水分利用效率提高17.32%。[结论]采用分根交替灌溉方式下的中等灌水量(W_2)有利于提高燕麦的生产效能,对盐分累积的控制效果较好。

[Objective]The effects of different irrigation methods and irrigation amounts on soil water,soil salt changes,and oat growth characteristics were explored to provide a scientific reference for improving crop production efficiency and soil water management in saline-alkali land.[Methods]Pot experiments were conducted with three irrigation treatments:conventional irrigation,fixed unilateral root-zone irrigation(FURI),and alternate partial root-zone irrigation(APRI).Three irrigation amounts were evaluated:W_1(60%θ_f—70%θ_f,θ_f is field water-holding capacity),W_2(70%θ_f—80%θ_f),and W_3(80%θ_f—90%θ_f).Conventional irrigation was used as the control.Therefore,there were a total of nine treatment combinations.[Results](1)Under the different irrigation treatments,the change trend of water content in each soil layer was basically the same.As irrigation amount increased,the effect of salt leaching was more significant.The deep water content of conventional irrigation was generally higher than that of the other two irrigation treatments.(2)Plant height,relative chlorophyll content of leaves,and oat quality increased with increasiong irrigation amount.The contents of crude fat,crude protein,andβ-glucan in oat were 7.02%,3.76%,and 6.06%,respectively,greater under the W_2 irrigation level than under the conventional irrigation level,but the SPAD values of oat leaves were lower under W_2,which affected the photosynthetic capacity of oat.(3)Soil salinity showed different degrees of accumulation as oat growth progressed,and the salt accumulation rate with alternate partial root-zone irrigation was the lowest.At the same time,soil salinity had a significant effect on oat root growth,water use efficiency,and yield.Total root length,total root surface area,and total root volume increased by 6.75%,6.92%,and 12.5%,respectively.Water use efficiency increased by 17.32%compared with conventional irrigation with the same irrigation amount(W_2).[Conclusion]The medium irrigation amount(W_2)under alternate partial root-zone irrigation was beneficial for improving the production efficiency of oat and was better at controlling salt accumulation.