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作 者 ：王小彬;蔡典雄;高绪科;张志田

期 刊 ：植物营养与肥料学报 1996年 2卷 4期 页码：297-304

关键词：耕作；容重；水分特征曲线；土壤保水剂；土壤结构剂；有机肥；化肥；

摘 要 ：本试验讨沧了容重及粒径大小对土壤持水性的影响,并对各种物料处理(或措施)的保水效果及其对土壤持水特征的影响进行了探讨。结果表明:随着容重的增大,土壤的透气和饱和导水率迅速下降;水分饱和时的土壤重量含水量(W％)因容重的增大而减少,但随着土壤水势的降低,W％不受容重所影响。<0.3mm和1～0.3mm的较小粒径土粒的持水量在高土壤水势范围内往往较大颗粒持水量为高;然而,随着土壤水势的下降(<-30kPa),较小土粒失水较快,较大土粒的持水量相对较高。保水剂和粪对土壤水的保持具有良好作用,当水势ψ>-200kPa,重量含水量W％>16％,保水剂和牛粪分别可使W％提高1.4％～9.9％和0.8％～2.5％。化肥在ψ>-50kPa,W％>19％时同样可提高土壤的持水能力(W％提高0.8％～3.0％)。土壤结构剂、秸秆时土壤持水特征曲线的影响范围较窄,在土壤水势较高的情况下才显示其保水效果。

Abstract:Lab studies were conducted to determine the effects of the soil bulk density and particle size, as well as different treatments (or practices) on soil water retention. The results showed that the rates of air and saturated water flow slowed down rapidly with increasing the bulk density. When the soil was saturated, the weight water content. (W%) decreased as the bulk density increased, however, W% was not affected by the bulk density with the decrease in the soil water potential. At a higher water potential, a smaller particle size of <0.3mm and 1-0.3mm contained more water than the bigger size did, but with the decrease in the soil water potential (<-30kPa), the bigger the size, the higher the water content. The water absorbent, then cattle dung, was superior in water retention to the others, the soil water content increased by 1.4% to 9.9% and 0.8% to 2.5% respectively, at >-200kPa (weight water%>16%). Application of fertilizers increased the soil water content by 0.8% to 3.0%, at>-50kPa (W%>19%). The effects of use of the soil conditioner and straw incorporation on water retention were limited only at a higher soil water potential.

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