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以室外田间小区试验测定和室内试验为手段 ,比较和评价了夏玉米生长期内不同耕作方式 (传统耕作、免耕及深松 )对耕层土壤物理性质和水力学特性的影响 ,定量描述了土壤干容重、地面入渗率以及饱和导水率等特性在作物整个生长季节内的时间变异性。深松耕作方式明显地减少了耕层土壤的干容重、增加了孔隙度 ,土壤孔隙尺度分布状况的改变使得土壤饱和时土壤的水分传导性能得以改善 ,但干旱时土壤的持水能力相对减弱。耕作方式引起的耕层土壤特性变化在整个夏玉米生长期内呈现出较强的时间变异性 ,尤其体现在土壤干容重、地面入渗率和饱和导水率等性能上。尽管耕作活动带来的土壤特性间的差异随着时间的延长有所减弱 ,但仍存在于夏玉米末期生长阶段中
The effects of different tillage practices (traditional tillage, no-tillage and deep subsoiling) on physical properties and hydraulic characteristics of topsoil in the summer maize growing season were compared and evaluated by means of outdoor field plot test and laboratory test. Quantitatively described Soil bulk density, ground infiltration rate and saturated hydraulic conductivity and other characteristics of the crop throughout the growing season of time variability. Subsoiling tillage significantly reduced the dry bulk density of topsoil and increased the porosity. The change of soil pore size distribution improved the soil moisture conductivity when soil saturation, but the water holding capacity of soil was relatively weakened during the drought. The changes of topsoil characteristics caused by tillage patterns showed strong temporal variability throughout the summer maize growth period, especially in soil dry weight, ground infiltration rate and saturated hydraulic conductivity. Although the differences in soil characteristics resulting from tillage activities have weakened over time, they remain in the late summer maize growth phase