海洋酸化影響下生物鈣化

Biocalcification under the Influence of OceanAcidification

李白(Joji Marau Misaele)

指導教授 ： 陳恕行

崑山科技大學/工程學院/機械工程研究所/碩士(2010年)

https://doi.org/10.6828/KSU.2010.00030

摘要

海洋是地球上最大的碳儲存槽，在海洋的鈣化每年可去除十億噸的碳，所以可減緩溫室效應。鈣化生物在碳循環及生態上均有重要地位。不過鈣化生物也受到正好是碳排放引起海水酸化的威脅。對鈣化機制的瞭解是協助增進鈣化的重要一步。本研究針對貝類研究，目的是探討是否有實務的方法可促進鈣化。
海水酸化在海岸地區特別明顯，這裡住有許多種類的鈣化生物。海水主體 pH值是在8.0~8.2之間，但在海陸交界處pH值低於7.0也會愈來愈常見。在這種條件下，碳酸鈣很難結晶。不利結晶的條件下，貝類的殼會變厚，所以生物機制在鈣化中扮演有趣且重要的角色。

關鍵字

碳循環 ； 貝類養殖 ； 鈣化生物 ； 海水酸化

並列摘要

Oceans are the biggest active carbon reservoir where calcification removes one giga ton C yearly and plays an important role in mitigating global warming. Calcifying organisms are an integral part to the carbon cycle as well as to the ecological community. However, calcifying organisms are threatened by ocean acidification caused by carbon emission and other human activities. Understanding fundamental calcifying mechanism is important to help increase calcification under the influence of acidification. The current work focuses on the calcification of shellfish and discusses whether practical measures like nutrition control, culturing density and soil management can help.
Many calcifying organisms live at the coastal regions where acidification is most profound. The pH of the main body of ocean is 8.0~8.2, while below 7 becomes commonplace for coastal water nowadays. Under such pH value, it is difficult to form calcium carbonate crystals chemically. It has been observed that low pH water often forces shellfish to produce thicker shells. The EDS result showed a high concentration of calcium. In the nacre the atomic ratio of CaCO3 was around 4.1: 1: 2 instead of 1:1:3. This suggests that biological process plays an interesting and important role in calcification.

並列關鍵字

carbon cycle ； calcifying organisms ； ocean acidification

參考文獻

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