不同耕作方法对土壤水温动态和春玉米产量的影响

针对华北高产农区连年旋耕导致耕层变浅、耕层生产能力下降的问题,在河北吴桥地区设置了6种耕作处理,研究大田条件下不同耕作方法对土壤水热状况与春玉米产量的影响.结果表明:1)不同耕作处理对土壤蓄水量的影响较大.耕作初期,深旋松耕处理土壤易于跑墒,随着时间推移,深旋松耕处理表现出利于降水入渗、储蓄更多水分的优势,并且越是干旱的时段,表现越突出,在抽雄吐丝期深旋松耕处理土壤蓄水量均极显著高于旋耕处理和间隔深松处理,其中深旋松耕50 cm处理的0～50 cm土层土壤蓄水量分别比旋耕处理和间隔深松处理增加37.67和26.41 mm,提高了60.57％和35.96％.土壤耕作结合地膜覆盖可以防止水分蒸发,提高土壤蓄水保墒能力,其中深旋松耕30 cm+地膜处理的0～30和0～50 cm土层土壤蓄水量分别比深旋松耕30 cm增加18.18和24.67 mm,提高35.26％和24.64％.2)单纯耕作方法对春玉米土壤温度没有太大影响.深旋松耕结合地膜覆盖会在春玉米封垄之前气温较低时有较好的保温效应,从而延长生育期5d左右,延长了灌浆时间,利于提高产量.3)耕作方式的不同对土壤水温状况有影响,并进而影响春玉米物候期、群体LAI、干物质积累和灌浆速率以及产量的形成.所有耕作处理中,深旋松耕处理的春玉米产量显著高于深松耕作和旋耕耕作,其中深旋松耕50 cm+地膜处理产量最高达12 698.93 kg/hm2,与长期旋耕耕作相比增产27.45％.总体来看最适宜本地区的耕作处理是深旋松耕结合地膜覆盖处理.

Effect of different tillage treatments on soil water,temperature changes and spring corn yield in high yield region in North China Plain

To address the problems of gradually shallow plough layer and low soil productivity resulted from continuous rotary tillage in high yield region in North China Plain,a field experiment was conducted to determine the effects of different tillage treatments on soil water,temperature changes and spring corn yield.The results showed that:1) Different tillage treatments greatly affected soil water storage.Deep rotary sub-soiling treatments easily lost soil water at early stage.Furthermore,the deep treatments facilitated precipitation infiltration and water storage in the soil during the experiment period,and this phenomenon appeared more prominent during the period of drought.During the spring corn silking stage,the level of soil water storage for deep rotary sub-soiling treatments was significantly higher than those of rotary tillage and interval sub-soiling treatment.It was found that the soil water storage in 0-50 cm soil layer for deep rotary sub-soiling 50 cm was higher than those of rotary tillage and interval sub-soiling by 37.67 and 26.41 mm respectively,which improved by 60.57% and 35.96%.Soil tillage combined with film mulch reduced soil water evaporation loss and improved soil water storage.For the treatment of deep rotary sub-soiling 30 cm plus film mulch,the soil water storage in 0-30 and 0-50 cm soil layer was increased by 18.18 and 24.67 mm when compared with that of treatment with deep rotary sub-soiling 30 cm,which equaled improvement of 35.26% and 24.64%,respectively;2) The effect of Simple tillage treatment on soil temperature was not obvious.Deep rotary sub-soiling +film mulch improved soil temperature,thus prolonged the growth period and grouting process,which boosted spring corn yield;3) Different tillage treatments affected soil water and temperature,thus further influenced the spring corn phenology,LAI,matter production,grouting process and yield.It was identified that the spring corn yield for the deep rotary sub-soiling treatment was significantly higher than those of rotary tillage and interval sub-soiling.The spring corn yield for deep rotary sub-soiling 50 cm+film mulch was 12 698.93 kg/hm² which equaled 27.45% improvement to that of the conventional rotary tillage.In a summary,based on the current study,it is concluded that the most suitable tillage method in future is deep rotary sub-soiling combined with film mulch in this area.