二氧化碳濃度與光強度對三種觀葉植物移除甲醛與光合作用之影響

Effects of Carbon Dioxide Concentration and Light Intensity on Formaldehyde Removal and Photosynthesis in Three Foliage Plants

將火鶴花‘粉冠軍’、白鶴芋'Petite'與彩虹竹蕉分別置於密閉熏氣箱（0.128 m^3），內放會釋放甲醛之木心板，以熏氣箱內含500或1200 ppm CO_2濃度與不同光強度（0、60或120μmol．m^(-2)．s^(-1)）處理，探討對植物吸收甲醛與光合作用的影響。結果顯示參試植物在黑暗環境中會釋放CO_2，氣孔導度低但於試驗3 h期間仍可少量移除熏氣箱內木心板釋放之甲醛，但移除量比照光環境下低。參試植物於60或120μmol．m^(-2)．s^(-1)光強度環境中，以1200 ppm CO_2處理3 h後之葉片氣孔導度皆低於500 ppm CO_2處理者，而且不利植物移除熏氣箱內的甲醛。光強度由60提高至120μmol．m^(-2)．s^(-1)可降低熏氣箱內更多的CO_2與甲醛濃度，使葉片淨光合作用速率與氣孔導度上升，使細胞間隙二氧化碳濃度下降。單位葉面積所移除的甲醛濃度之排序為火鶴花＞白鶴芋＞彩虹竹蕉。在本研究參試環境條件下，彩虹竹蕉的淨光合作用與氣孔導度皆最低而細胞間隙CO_2濃度最高，移除熏氣箱內CO_2與甲醛之能力最低。

"Anthurium andraeanum Linden. 'Pink Champion', Spathiphyllum kochii Engler & Krause 'Petite', and Dracaena marginata Lam. 'Tricolor Rainbow' were placed in airtight chambers, respectively, each with a fresh wooden board that released formaldehyde. The experiment was constructed with two initial CO_2 concentrations (500 or 1200 ppm) and three light intensities (0, 60 or 120μmol．m^(-2)．s^(-1) PPF) for three hours. Results showed that CO_2 concentration increased and formaldehyde reduced slightly in the chamber for plants under dark conditions. Under light conditions, plants with 500 ppm CO_2 had higher stomatal conductance and reduced more formaldehyde than those with 1200 ppm CO_2. Increased light intensity resulted in increased net photosynthetic rate, stomatal conductance, and removal rates of formaldehyde and CO_2. The efficiency of removing formaldehyde per leaf area ranked as: Anthurium＞Spathiphyllum＞Dracaena. Dracaena exhibited the lowest net photosynthetic rate, stomatal conductance and removal rates of formaldehyde and CO_2 under the conditions constructed in this study."