采用四种灌溉方式和有无秸秆覆盖的组合处理,研究了灌溉与秸秆覆盖结合条件下冬小麦农田的小气候特征。结果表明,从2月份开始,覆盖处理在14:00时的土壤温度明显低于不覆盖处理。秸秆覆盖能够降低近地面空气湿度和提高近地面空气温度,在灌溉条件下表现尤为明显。灌溉能够降低近地面的湍流交换系数和湍流热通量,提高潜热通量,而秸秆覆盖的作用相反。秸秆覆盖具有增强灌溉水入渗能力的作用。秸秆覆盖显著降低冬小麦的产量和水分利用效率(WUE)。
After Feb. 2003, soil temperature at 14:00 p.m. of mulching treatments was much lower than that of un-mulching treatment. The air humidity of 5 cm above the ground under the condition of irrigation was decreased and the air temperature of 5 cm above the ground increased by straw mulching. The turbulent coefficient and turbulent flux was decreased and straw mulching increased the latent heat flux by irrigation and vice versa. Mulching, leading to the higher soil moisture content could enhance the penetrating ability of irrigation water. The yield and WUE of winter wheat were obviously reduced by straw mulching.
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