The coral reef ecosystem is one of the most productive ecosystems in the ocean, and is also an important calcium carbonate deposition region. Because excess production is very low in coral reefs, organic carbon reservoirs are very limited. During the calcification process, each mole of CaCO3 will produce 1 mol of CO2, approximately 60% of which will be released into the atmosphere through the sea-air interface. This causes coral reefs to be large inorganic carbon reservoirs, but at the same time, most coral reefs act as atmospheric CO2 sources (which also act as sinks in some coral reefs). Therefore, clarifying the sea-air CO2 exchange flux and carbon storage is critical for understanding the carbon cycle in coral reef ecosystems. In this paper, we summarize the carbon cycle processes in the coral reefs of the South China Sea (SCS) and estimate the total CO2 budget and carbon reserves. According to current research, the coral reefs in this area act as a source of atmospheric CO2, releasing 0.37−1.59 × 1011 g C a-1 into the atmosphere. Owing to their extremely high biological productivity and carbonate productivity, the carbon reserves of coral reefs in the SCS range from 1.66–3.78 × 1012 g C a-1, which is an order of magnitude greater than the CO2 emissions at the sea–air interface. Overall, coral reefs in the SCS are important carbon storage areas. As the current results are still approximate, a more comprehensive and in-depth investigation is needed to clarify the carbon source/sink processes, regulatory mechanisms, and carbon storage capacity of SCS coral reefs.

中文翻译：

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南海珊瑚礁生态系统的碳预算


珊瑚礁生态系统是海洋中生产力最高的生态系统之一，也是重要的碳酸钙沉积区。由于珊瑚礁的过量生产非常低，因此有机碳库非常有限。在钙化过程中，每摩尔CaCO3将产生1摩尔CO2，其中大约60%将通过海-气界面释放到大气中。这使得珊瑚礁成为大型无机碳库，但同时，大多数珊瑚礁充当大气二氧化碳源（在一些珊瑚礁中也充当汇）。因此，阐明海-气二氧化碳交换通量和碳储存对于理解珊瑚礁生态系统的碳循环至关重要。在本文中，我们总结了南海珊瑚礁的碳循环过程，并估算了总二氧化碳预算和碳储量。根据目前的研究，该地区的珊瑚礁是大气二氧化碳的来源，向大气中释放了0.37−1.59 × 1011 g C a-1 。南海珊瑚礁因其极高的生物生产力和碳酸盐生产力，碳储量为1.66~3.78×1012 g C a-1，比海气界面二氧化碳排放量高​​一个数量级。 。总体而言，南海珊瑚礁是重要的碳储存区。由于目前的结果仍然是近似的，需要更全面和深入的调查来阐明南海珊瑚礁的碳源/汇过程、调节机制和碳储存能力。