This study explored the physiological responses of the coral Pocillopora damicornis to high nitrate concentrations and thermal stresses. The expression of heat shock proteins Hsp60 and Hsp32, Symbiodiniaceae density, Chl a concentration, Fv/Fm, H₂O₂ scavenging, and caspase 3 activity varied during 60 h incubations at 28 °C or 32 °C, ambient or high nitrate (~10 μM) concentrations, and their combinations. In combined stresses, corals showed a rapid and high oxidation level negatively affecting the Symbiodiniaceae density and Chl a concentration at 12 h, followed by caspase 3 and Hsps upregulations that induced apoptosis, bleaching and tissue detachment. Corals under thermal stress showed the highest oxidation and upregulation of Hsps and caspase 3 resulting in coral discoloration. High nitrate treatment alone did not seriously affect the coral function. Results showed that combined stress treatment severely affected coral physiology and, judging from the condition of detached tissues, these corals might have lower chances to recover.

本研究探讨了珊瑚Pocillopora damicornis对高硝酸盐浓度和热应激的生理反应。热休克蛋白 Hsp60 和 Hsp32 的表达、共生菌科密度、Chl a浓度、Fv/Fm、H ₂ O ₂清除和半胱天冬酶 3 活性在 28 °C 或 32 °C、环境或高硝酸盐培养 60 小时期间发生变化（ ~10 μM) 浓度，以及它们的组合。在合并的应力，珊瑚呈现快速和高氧化水平负面地影响Symbiodiniaceae密度和叶绿素一个12 小时时的浓度，然后是半胱天冬酶 3 和 Hsps 上调，诱导细胞凋亡、漂白和组织脱离。热应激下的珊瑚表现出最高的 Hsps 和 caspase 3 氧化和上调，导致珊瑚变色。单独的高硝酸盐处理并没有严重影响珊瑚的功能。结果表明，联合应激处理严重影响了珊瑚的生理机能，从脱离组织的状况来看，这些珊瑚的恢复机会可能较低。