土壤表層蒸發量推估之研究

Study on Estimation of Evaporation by Surface Soil

翁懿凡(I-Fan Weng)

指導教授 ： 張德鑫

中原大學/工學院/土木工程學系/碩士(2006年)

https://doi.org/10.6840/cycu200600589

摘要

在陸地水循環的過程，降雨與蒸發現象扮演著相當重要的角色。蒸發簡單的說就是將水由液體轉化為氣體進入大氣中的作用；影響此水面蒸發作用的原因有環境溫度、溼度、太陽輻射和風速等氣象條件。地表之蒸發作用通常發生在無降雨時，此時土壤含水量的多寡及土壤溫度會導致蒸發速率的改變，而各氣象因子與陸地水文因子之間也會相互影響，故造成在研究上格外複雜。因此本文針對桃園地區紅土與大甲溪河砂的蒸發狀況做進一步研究，研究所得之結果，將有助於未來未飽和層土壤含水量模式之建立。
本研究將依照土壤含水量變化與土水蒸發比的相互關係，得知土壤蒸發過程分為三個階段：(1)穩定蒸發階段，(2)蒸發率顯著下降階段，(3)蒸發率微弱階段；且依實驗結果，得知各階段之土樣蒸發推估式。
實驗結果顯示土壤含水量與土水蒸發比之間，會依特定之土壤水分常數呈分段式線性關係。且迴歸分析之後，可得迴歸直線之判定係數除蒸發率微弱階段外，皆大於0.7。本研究之結果將有助於整個水文循環模式之建立，並極具參考價值。

關鍵字

土表蒸發

並列摘要

In the process of the land water circulation, rainfall and evaporation are both playing a quite important role. In a word, evaporation is the function of the water changing form the liquid to the gas and finally entering into the atmosphere. The evaporation function of the earth’s surface usually takes place while there is no rainfall, at this moment, the number of the water content of the soil and soil temperature will cause the change of the evaporating speed, and each meteorological factor and land hydrology factors will also influence each other, so it is extremely complicated in studying. Therefore, this text aims at the evaporation situations of the laterite of the district of Taoyuan and the sand of the Dajia River and studies these situations further. The outcome of the study will contribute to the model setting up of the water content of the non-saturated layer of the soil in the future.
This study will be according to the between the change of the water content of the soil and the ratio of soil to water, and shape a straight line. Then, we can find the process of the soil evaporation can divide into three stages: (1) steadily evaporation, (2) the evaporating rate drops apparently, (3) the evaporating rate becomes faint; and we can get the formula of the soil evaporation in each stage depending on the experimental result.
The experimental result shows that the interrelationship between the change of the water content of the soil and the ratio of soil to water will present a segmenting type of linear relationship depending on specific soil moisture constant. And, after the regression analysis, the R-square values are all greater than 0.7 besides the stage of the evaporating rate becoming faint. The result of this study could contribute to the setting-up of the model of the whole hydrology circulation, and it could also has much reference value.

並列關鍵字

evaporation ； surface soil

參考文獻

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