土壤水分遲滯現象之實驗與理論分析

Theoretical and Experimental Studies of Soil Moisture Hysteresis Phenomenon

黃漢誠(HAN-CHEN HUANG) ； 楊欣常(HSIN-CHANG YANG) ； 馬國宸(KUO-CHEN MA) ； 陳主惠(CHU-HUI CHEN) ； 譚義績(YIH-CHI TAN)

《台灣水利》 49卷2期 (2001/06) Pp. 30-45

https://doi.org/10.6937/TWC.200106_49(2).0004

摘要

未飽和土壤水分會因乾燥、濕潤交替的歷程而發生遲滯現象，一般在土壤水分估計的計算上，多未能真實反應實際的土壤水分變化情形，要能準確的計算則必須在乾燥、濕潤交替變化的環境中考慮遲滯現象的發生及其水力特性的變動。本文以土壤水分遲滯實驗配合理論模式，探討未飽和土壤保水特性及比水容積在乾燥、濕潤歷程下的變化；研究顯示在乾燥、濕潤交替循環的歷程中土壤水分特性曲線與比水容積的變化並非以單一關係存在，透過模式之分析可使遲滯現象中土壤水力特性的關係明朗化，模式預測與實驗之比較在各例中最大之土壤含水量誤差為4.9%，而修正後之模式可將最大之誤差降至2%。

關鍵字

遲滯現象 ； 保水曲線 ； 比水容積

並列摘要

It is difficult to know the exact variation of water content due to the occurrence of the hysteresis. According to experiments of the hysteresis, the variation of moisture retention and specific water capacity of unsaturated soil in alternating environments of wetting and drying is discussed. The result showed that there was not a simple relationship among those hydraulic characteristics in the unsaturated soil. The hysteretic model can reflect the variation of water content due to the effect of the hysteresis and acquire a better estimation of the relationship between specific water capacity and matric head. The maximum error between the predicted value of theoretical model and the results of experiments is 4.9%, which was resulted from the method of boundary curve. Moreover, the estimation by using scanning curve can lower the error from 4.9% to 2.0%.

並列關鍵字

Hysteresis ； Soil-moisture retention curve ； Specific water capacity