【摘要】 麦田进行秸杆覆盖后 ,由于地表热学性质和动力学性质的变化 ,使近地层水热状况发生改变 .1 997年 3月份小气候观测表明 :覆盖后白天能提高近地层的空气温度 ,减小近地层空气湿度 ,明显降低地温 ;覆盖后麦田乱流交换系数增大 ,显热通量增大 ,潜热通量减小 ,亦即用于土壤蒸发的能量减小 ,使土壤蒸发减小 ,从而从能量平衡角度解释了覆盖的保墒机理更多还原

【Abstract】 Owing to changes of thermodynamic and dynamic characteristics of the ground surface in mulched wheat field, the water and heat conditions near the surface in the field change greatly. According to the measurements of microclimate in wheat fields conducted in March 1997, air temperature and turbulent coefficient near the surface increased and air humidity as well as soil temperature decreased in mulched fields. Furthermore, mulching led to the increase of sensible heat flux and the decrease of latent heat flux, and thus the decrease of water evaporation from soil. Therefore the influencing mechanism of mulching on reserving soil moisture can be interpreted from the viewpoint of energy balance.更多还原