Coral Ecophysiology Team, Centre Scientifique de Monaco, 8 Quai Antoine 1er, MC-98000 Monaco, Monaco.
IFD-ED 129, Sorbonne Université Sciences (Formerly UPMC Université Paris VI), CEDEX 05, 75005 Paris, France.
Int J Mol Sci. 2023 Feb 4;24(4):3119. doi: 10.3390/ijms24043119.
Dissolved inorganic phosphorus (DIP) is a limiting nutrient in the physiology of scleractinian corals. Anthropogenic addition of dissolved inorganic nitrogen (DIN) to coastal reefs increases the seawater DIN:DIP ratio and further increases P limitation, which is detrimental to coral health. The effects of imbalanced DIN:DIP ratios on coral physiology require further investigation in coral species other than the most studied branching corals. Here we investigated the nutrient uptake rates, elemental tissue composition and physiology of a foliose stony coral, , and a soft coral, , exposed to four different DIN: DIP ratios (0.5:0.2, 0.5:1, 3:0.2, 3:1). The results show that had high uptake rates of DIN and DIP, proportional to the seawater nutrient concentrations. DIN enrichment alone led to an increase in tissue N content, shifting the tissue N:P ratio towards P limitation. However, had 5 times lower uptake rates and only took up DIN when the seawater was simultaneously enriched with DIP. This double uptake of N and P did not alter tissue stoichiometry. This study allows us to better understand the susceptibility of corals to changes in the DIN:DIP ratio and predict how coral species will respond under eutrophic conditions in the reef.
溶解无机磷（DIP）是石珊瑚生理学中的限制营养物质。人为向沿海珊瑚礁添加溶解无机氮（DIN）会增加海水中 DIN：DIP 比值，从而进一步增加磷限制，这对珊瑚健康有害。不平衡的 DIN：DIP 比值对珊瑚生理学的影响需要在除了研究最多的分枝珊瑚以外的珊瑚物种中进一步研究。在这里，我们研究了四种不同 DIN：DIP 比值（0.5:0.2、0.5:1、3:0.2、3:1）下的叶状石珊瑚和软珊瑚的营养吸收速率、元素组织组成和生理学。结果表明，对 DIN 和 DIP 具有高吸收速率，与海水中的营养浓度成正比。单独的 DIN 富集导致组织 N 含量增加，使组织 N：P 比朝着磷限制的方向转变。然而，的吸收速率低 5 倍，只有当海水同时富含 DIP 时才会吸收 DIN。这种氮和磷的双重吸收并没有改变组织化学计量。这项研究使我们能够更好地了解珊瑚对 DIN：DIP 比值变化的敏感性，并预测珊瑚物种在珊瑚礁富营养化条件下将如何反应。
