土壤表層蒸發量與皿蒸發量關係之研究

Study on the Relationship between Evaporation by Surface Soil and Pan Evaporation

王震釜(Zhen-Fu Wang)

指導教授 ： 張德鑫

中原大學/工學院/土木工程學系/碩士(2008年)

https://doi.org/10.6840/cycu200800482

摘要

蒸發量在農業工程、土木水利工程及氣象科學上，均扮演相當重要的角色。蒸發量除了自由水面蒸發量外，土面蒸發量亦是一個十分重要的課題，尤其在灌溉排水與農田水利上更是不可忽視的基本資料。
影響土壤蒸發量與水面蒸發量的因素很多，舉凡如太陽輻射、濕度、風速或氣壓等氣象條件，均會影響蒸發量之多寡。其次根據文獻資料也發現，土壤含水量多寡及土壤種類也會直接影響土壤蒸發量，因此本文針對桃園地區紅土與南崁溪河砂兩種不同介質的蒸發過程進行研究分析，探討同氣象條件之不同土樣，和不同氣象同土樣之結果做比較分析，研究所得結果，將有助於土壤含水量與蒸發量關係模式之建立。
本研究現地實驗地點為中原大學體育館旁空地，分別觀測紅土與河砂兩種介質從飽和狀態至水份含量甚低時之每日含水量變化，再依照土壤含水量變化與土水蒸發比的相互關係繪圖，繪製含水量與蒸發比之無因次圖，由圖中可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，以及(3)蒸發率微弱階段。最後依實驗之結果，可得知各階段土樣蒸發推估式。
為了讓氣象站資料可直接做土壤蒸發量之估算，故本研究將實驗量測之自由水面蒸發量與氣象站之蒸發資料，做分析比較，並得其關係式。並將實驗之結果配合數學模型，了解土面蒸發量與水面蒸發量之全期相關性，經迴歸分析後，其迴歸判定係數均大於0.8具有不錯之相關性，在農業灌溉，水文模式的建立有很大的幫助，且極具有考價值。

關鍵字

蒸發 ； 蒸發皿 ； 土壤表層

並列摘要

Evaporation has a very important position in agriculture civil engineering, hydraulic engineering or in the science of meteorology. The influence soil transpiration rate and the water surface transpiration rate factor are very many, the solar radiation, the wind speed, the pressure. 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 influence each other. By analyzing and improving the previous relative searches of this topic, the sandy-loam and clay-loam soil were chosen for the experiment. The evaporation from the different soils under the same meteorological conditions and that from the same soils under the different meteorological conditions were studied and compared. 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.
The experiment was performed at the “The block place nearby stadium in Chung Yuan Christian University”. The daily evaporation of sandy-loam and clay-loam soil was calculated from the saturated state to the air-dry state, and therefore, the evaporation ration (the evaporation from soil to that from water) was plotted. We can find the process of the soil evaporation can divide into three stages: (1) steadily evaporation, (2) the evaporation rate drops apparently, (3) the evaporation rate become faint. We can get the formula of the soil evaporation in each stage depending on the experimental result.
We use mathematical model to match the result can understands the soil surfaced road transpiration rate and the water surface transpiration rate relations. And after the regression analysis, the R-square values are all greater than 0.8. It has pretty good relationships.

並列關鍵字

Evaporation ； Surface soil. ； Pan Evaporation

參考文獻

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