温度对土壤水分保持影响的研究

TEMPERATURE EFFECT ON SOIL WATER RETENTION

本文对陕西省四种典型土壤持水曲线的温度效应进行了定量研究。结果表明，表征土壤水势温度效应的水势温度系数，随土壤质地加重而增大，随含水量增加而降低；脱湿过程水势温度系数大于吸湿过程的相应数值；低温段（5℃-20℃）土壤水势温度系数大于高温段（20℃—50℃）；温度升高，土壤水分特征曲线的滞后效应有降低趋势。表面张力—粘滞流理论（STVF）适于描述温度对质地较轻土壤水势的影响，G（θ）函数可用以描述温度对包括质地较轻土壤水势的影响，并可取得满意的结果。

The temperature effect on water retention curves for four typical soils in Shaanxi Province were studied quantitatively in the work. The results showed that the temperature Coefficients of water potential increaed with the increase of soil clay content and decreased with the increase of soil water content; there were lagr tempereture Coeffients of water potential in the drying process than in the wetting; in the low temperature range (5℃-20℃), the temperature coefficients of water potential were greater than the high temperature range (20℃- 50℃); the hystersesis effecd on water retention curves tended to decrease with increasing temperature;for the light texture soils, the the of temperature on the soil wafor potential can be explained with the STVF model; for flne-teXtutal soil (include the light texture soils), the Gain factor model seemed to perform satisfactorily.