Effects of Temperature on the Oxygen-and Fluorescence-Based Estimates of Photosynthetic Parameters in the Reef Coral Stylophora pistillata

溫度對萼柱珊瑚光合作用的影響：溶氧法與螢光法的比較

吳岱穎(Tai-Ying Wu) ； 戴昌鳳(Chang-Feng Dai) ； 樊同雲(Tung-Yung Fan)

《臺灣水產學會刊》 33卷3期 (2006/09) Pp. 253-263

https://doi.org/10.29822/JFST.200609.0006

摘要

本研究利用呼吸儀和水下螢光儀(diving pulse amplitude modulate, Diving PAM)以及測量珊瑚組織參數，包括蛋白質濃度、葉綠素a濃度和共生藻密度等方法，探討萼柱珊瑚(Stylophora pistillata)在不同溫度(20、25、28℃)珊瑚礁中型生態箱養殖10天對其光合作用的影響。結果發現各項組織參數、呼吸儀測得的最大總光合作用速率(P(上標 g) (下標max))、光合作用效率(α)和半飽和光照(I(下標 k))，以及水下螢光儀測得的光合作用效率(α)及光系統II的光化學效率(F(下标 v)/F(下标m))等都無顯著差異。然而，25和28℃下珊瑚的最大電子傳遞速率(ETR(下標 max))和半飽和光照(I(下標 k-ETR))皆顯著高於20℃的珊瑚，顯示光系統II的電子傳遞速率對溫度的反應較敏感，並且最大電子傳遞速率和半飽和光照隨溫度上升而增加。此外，在3種溫度下，當光照強度低於400 μE m^(-2)s^(-1)，或是總光合作用速率(gross photosynthesis rate, GP)低於14 μmol O2m^(-2)s^(-1)時，GP與ETR都呈現直線關係，顯示在中等強度的光照環境下，水下螢光儀可能具有以非破壞方式快速估計珊瑚初級生產力的潛力。

關鍵字

螢光法 ； 光合作用 ； 造礁珊瑚 ； Stylophora pistillata ； 溫度

並列摘要

The effect of temperature on the O2-based and chlorophyll fluorescence of Photosystem Ⅱ (PSII)-based parameters of photosynthesis in the reef coral Stylophora pistillata was investigated. Coral nubbins were maintained in coral reef mesocosms at three temperature levels (20, 25 and 28℃) for ten days. The maximum PSII quantum efficiency (F(subscript v)/F(subscript m)) and electron transport rates (ETR) were measured by diving pulse amplitude modulate (PAM) fluorometry and the rate of O2 evolution was carried out by oxygen respirometry. The tissue composition, maximum rate of gross photosynthesis (P(superscript g) (subscript max) and sub-saturation irradiance (l(subscript k)) measured by respirometry, photosynthetic efficiency (α) measured both by respirometry and PAM, as well as (F(subscript v)/F(subscript m)) were similar among different temperature treatments. However, the maximum electron transport rate of photosynthesis (ETR(subscript max)) of corals at 25 and 28℃ was two times higher than that of corals at 20℃. In addition, the sub-saturation irradiance (I(subscript k-ETR)) was significantly higher at 28 and 25℃ than that at 20℃. It suggests that the photosynthetic process of PSII electron transport rate is rather sensitive to temperature and ETR(subscript max) and I(subscript k-ETR increased with increasing temperature. Furthermore, a similar linear relationship between gross photosynthesis rate (GP) and ETR was found under irradiances below 400 μE m^(-2)s^(-1) or GP less than 14 μmol O2 m^(-2)s^(-1) at the three temperature treatments. This suggests that diving-PAM may provide a quick and non-invasive way to estimate primary productivity of corals under moderate irradiances.

並列關鍵字

Fluorescence ； Photosynthesis ； Reef coral ； Stylophora pistillata ； Temperature