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运用张力计法对河南省７种主要类型土壤低吸力段持水特性进行了研究，按照θ＝ＡＳ－Ｂ模式建立了低吸力持水曲线方程，分析了土壤性质与持水特性的关系。结果表明：各类型土壤的水分变化过程均存在明显的滞后圈，其中两合土、立黄土滞后圈宽度较大，红胶土和砂姜黑土滞后圈宽度最窄，且各类土壤均呈现从表层到深层滞后圈由宽变窄的趋势。从Ａ·Ｂ值和比水容量进行评价，立黄土、两合土持水特性最好，潮褐土、淤土次之，砂姜黑土、红胶土和黄褐土较差。在０．０２０～０．０９０ＭＰａ吸力段，土壤持水量与质地关系密切，在极低吸力段，土壤持水量与容重、孔隙度关系密切，有机质含量与整个低吸力段的持水量均有正相关关系；Ａ·Ｂ值和比水容量与质地、容重及总孔隙度有密切关系，用Ａ·Ｂ值和比水容量的大小可作为土壤抗旱性的综合指标。
Tensiometer was used to study the water holding characteristics of the low suction section of seven main types of soil in Henan Province. According to the equation of θ = AS-B, a low suction water retention curve equation was established and the relationship between soil properties and water holding characteristics was analyzed. The results show that there are obvious hysteresis loops in the variation of soil moisture, of which the hysteresis width of the two loess and the loess is larger, the width of the hysteresis loop of the red clay and the sapropenetate black soil is the narrowest, The hysteresis loop from the surface to the deeper narrowing trend. From the value of A · B and the specific water capacity, the water-holding characteristics of the loess and the loam are the best, followed by the cinnamon soil, silt soil, sand lime black soil, red clay soil and yellow cinnamon soil. In the suction section of 0.020-0.090MPa, soil water content and texture are closely related. In the extremely low suction section, the relationship between soil water content and bulk density and porosity are close, and the organic matter content is positively correlated with the water holding capacity of the whole low suction section Relationship; A · B value and specific water capacity and texture, bulk density and total porosity are closely related, with A · B value and specific water capacity can be used as a comprehensive index of soil drought resistance.