【摘要】 以东北雨养区春玉米农田为研究对象,分析春季和秋季2个整地时期对农田土壤含水量、土壤物理性状、土壤养分含量以及玉米产量等的影响。结果表明:秋整地可显著提高玉米产量,与春整地相比增产8.7%(P<0.05)。秋整地处理下土壤水分状况得到显著改善,播种前和苗期耕层土壤(0-20cm)含水量分别比春整地高18.9%和5.6%。整地时期对种子层土壤(0-10cm)的物理特性影响不明显(P>0.05),但秋整地可显著改善10-40cm的根层土壤物理性状,其中土壤孔隙度比春整地平均提高10.0%,而土壤容重则比春整地平均下降11.6%。整地时期对0-40cm层次的土壤硬度和土壤养分含量影响不显著。可见,秋整地主要通过改善土壤物理蓄水性能和减少水分散失提高土壤水分含量,保证较高的成株率和成穗率,进而利于玉米高产稳产。更多还原

【Abstract】 In this study,two treatments of soil preparation periods in spring(ST) and in autumn(AT) were conducted to investigate their impacts on soil water storage,soil physical properties,soil nutrient content and corn yield in rain-fed area of northeast China.Results showed that grain yield was significantly higher by 8.7%(P<0.05) in the AT plots than that in the ST plots.The corresponding higher values of soil water contents in the 0-20 cm depth were 18.9% and 5.6% in sown stage and seedling stage,respectively.There was no significant difference between two treatments in soil physical properties in the 0-10 cm layer(P>0.05),whereas AT improved soil physical properties in the 10-40 cm depth significantly.Total soil porosity in the 10-40 cm depth in AT was higher than that in ST by 10.0%.Soil bulk density of 10-40 cm depth in AT was lower than that in ST by 11.6%.There was no significantly difference between two treatments on soil penetration resistance and soil nutrient content in the 0-40 cm depth.Results indicate that soil preparation in autumn can improve the capacity of soil water storage and reduce soil evaporation,resulting in higher soil water content in the topsoil layer.Consequently,soil preparation in autumn can enhance corn yield mainly through increasing seedling survival rate and ear-bearing rate.更多还原