【摘要】 本文以降水、土壤、作物三者处于同一系统的观点,论述了坝下丘陵旱地土壤水分的垂直变化规律,按照降水规律把土壤水分年际变化分为四个阶段,即11—3月冻结期,4—6月失墒期,7—8月补墒期,9—10月失墒期,并分析了各阶段的土壤贮水量、土壤耗水量等因子,指出干旱是当地农业生产的制约的因素,夏旱甚于春旱。针对当地降水少,易旱的特点提出了调节作物播种期、开源节流等改进旱农技术的措施。更多还原

【Abstract】 With rainfall,soils and crops viewed as in the same system,this paperdeals with the laws of vertical changes in soil moisture in hilly rainfedlands at Baxia.The changes in soil moisture from year to year havebeen classified into four stages according to the laws of rainfall,i.e.thefrozen stage from Nov.to Mar.;the soil moisture lost stage from Ap-ril to June;the soil moisture storage stage from July to Aug.;and thesoil moisture lost stage from Sept to Oct.Also,such factors as the am-ount of soil moisture storage and soil water consumption in each stageare analysed and it is pointed out that drought is a major constraintin the local agricultural production.Based on the local characteristicsof less rainfall and being liable to drougnt,such agrotechnicel measuresas regulating crop sowing periods and developing new sources and beingmore economical to improve rainfed agriculture are suggested in this pa-per更多还原