在雲霧森林中光合作用常會受到雲霧影響，因雲霧森林長期處在高濕度的環境下，霧水會沉降於葉表面造成氣孔被水滴堵塞，使光合作用降低。然而，在棲蘭山相關研究中台灣扁柏有相反的現象，江佳穎 (2011)運用自製密閉氣室使用人造霧的實驗。結果顯現台灣扁柏在供霧10分鐘、30分鐘及60分鐘處理下，供霧能提高光合作用率。因此本研究想了解霧水對光合作用的影響，在霧林帶與非霧林帶樹種之間是否有差異。探討不同供霧時間對霧林帶樹種及非霧林帶樹種光合作用的影響。本研究採用實驗室內的操控性實驗。實驗運用的密閉氣室量測系統包含密閉氣室、CO2量測系統、供霧設備、環境控制系統及資料記錄處理器。材料選用霧林帶樹種一種及非霧林帶樹兩種，進行霧水對光合作用影響的實驗。實驗結果霧水對霧林帶及非霧林帶樹種皆會使光合作用降低。在不同長短的供霧處理，供霧10分鐘、30分鐘、60分鐘及3小時，台灣扁柏因霧水影響使降低光合作用17%、15%、9%及18%。台灣肖楠因霧水使光合作用降低2%、0%、3%及6%。茄苳因霧水影響使光合作用降低5%、13%、20%及29%。在供霧處理10分鐘及30分鐘，受霧水影響使光合作用降低的比例最大為台灣扁柏，供霧處理60分鐘及180分鐘，降低的比例最大為茄苳。在霧林帶環境受雲霧籠罩的時間常長達60分鐘以上，由結果可知霧林帶的環境較不利於茄苳生長。在供霧處理60分鐘及180分鐘霧水對光合作用之影響，因台灣扁柏及台灣肖楠皆具有佛洛林環，此構造能避免氣孔導度降低。因此在供霧長達1小時以上，台灣扁柏及台灣肖楠受霧水影響使光合作用降低的比例較茄苳少。

In cloud forests, clouds often affect photosynthesis. Due to long term exposure to high humidity environments, clouds cause water vapor to condense into droplets on leaf surfaces, thus clogging the pores, reducing the rate of photosynthesis. Previous studies at the Chi-Lan Mountain site, however, showed an opposite phenomenon of enhanced photosynthesis when Chamaecyparis obtusa var. formosana saplings were treated with artificial fog under manipulated experiments. In this study, to further examine the effect of fog water on photosynthesis, measurements of photosynthesis were taken using a closed chamber measuring system, under various timespans of fog treatments on cloud forest tree and non-cloud forest tree species. The closed chamber measuring system includes a closed chamber, Li-820 CO2 gas analyzer advantages, ultrasonic humidifier, environmental control systems, and a measurement and control datalogger. Results showed that fog water reduced photosynthesis in both cloud forest tree and non-cloud forest tree species. After 10, 30, 60, and 180 minutes of fog exposure, photosynthesis was reduced by 17%, 15%, 9%, and 18% in Chamaecyparis obtusa var. formosana, 2%, 0%, 3%, and 6% in Calocedrus formosana (Florin) Florin, 5%, 13%, 20%, and 29% in Bischofia javanica Blume. Reduction of photosynthesis was largest after 10 and 30 minutes of fog exposure on Chamaecyparis obtusa var. formosana, and Bischofia javanica Blume after 60 to 180 minutes. The results showed that cloud forest environments is not conducive to Bischofia javanica Blume growth. Chamaecyparis obtusa var. formosana and Calocedrus formosana (Florin) Florin have Florin rings, thus reduction of photosynthesis was less than Bischofia javanica Blume when fog exposure exceeded 60 minutes.

1. 前言 ............................................................ 1
1.1 雲霧森林 ................................................................... 1
1.2 霧對植物的影響 ................................................................... 2
1.3 葉濕對光合作用的影響 .............................................. 2
1.4 台灣雲霧森林葉濕相關研究 ........................................... 3
1.5 研究目的 ........................................................ 4
2. 材料與方法 ....................................................... 5
2.1 實驗設計 ........................................................ 5
2.2 儀器 ........................................................... 5
2.2.1 密閉氣室 ...................................................... 5
2.2.2 CO2量測系統 ................................................... 6
2.2.3 供霧設備 ...................................................... 8
2.2.4 環境控制系統 ................................................... 9
2.2.5 資料記錄處理 .................................................. 11
2.3 實驗樹種 ....................................................... 12
2.4 苗木前處理 ..................................................... 12
2.5 實驗操作 ....................................................... 15
2.5.1 光合作用率計算 ................................................ 15
2.5.2 區分供霧處理中光量及霧水對光合作用之影響 ........................... 17
3. 前測 ........................................................... 19
3.1 密閉氣室內光環境 ................................................ 19
3.1.1 光量計校正 ................................................... 19
3.1.2 水平及垂直面光量的變化 ......................................... 20
3.2 供霧率測試 ..................................................... 26
3.3 人工供霧對密閉氣室內環境因子的影響 .................................. 27
3.4 測試放置實驗小苗之生長箱一天CO2濃度變化 ............................. 29
3.5 計算進行光合作用實驗時間 .......................................... 29
4. 結果 ........................................................... 31
4.1 實驗樹種光反應曲線 .............................................. 31
4.1.1 台灣扁柏之光反應曲線 ........................................... 32
4.1.2 台灣肖楠之光反應曲線 ........................................... 33
4.1.3 茄苳之光反應曲線 .............................................. 34
4.2 不同供霧處理對光合作用之影響 ...................................... 34
4.3 光量及霧水對光合作用之影響 ........................................ 39
4.4 統計分析 ....................................................... 42
4.5 不同供霧處理中反射光的變化情形 ..................................... 45
5. 討論 ........................................................... 49
5.1 供霧處理對光量及光合作用之影響 ..................................... 49
5.2 霧水對光合作用的影響 ............................................. 50
5.3 與江佳穎(2011)結果之比較 ......................................... 51
6. 結論 ........................................................... 53
7. 未來研究建議 ..................................................... 55
8. 引用文獻 ........................................................ 57
9. 附錄 ........................................................... 59

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