IntroductionThe impact of ocean acidification (OA) and nanoplastics (NPs) on harmful algal blooms (HAB) has emerged as a major global concern. However, the combined effects of OA and NPs on the HAB species are poorly understood.MethodsIn this study, dinoflagellate Prorocentrum donghaiense, a typical HAB species, was exposed to varying concentrations of NPs (108.15 ± 8.52 nm) (0, 5, 10, and 15 mg L−1) and CO2 (low CO2: 417 ppm, pH: 8.00 and high CO2: 1045 ppm, pH: 7.73) for seven days to investigate the combined effects of OA and NPs.Results and discussionThe findings revealed that NPs inhibited the growth of P. donghaiense by inducing oxidative stress, as indicated by elevated malondialdehyde (MDA) content and decreased carotenoid/chlorophyll-a ratio, even though photochemical efficiency (φP0, ψ0, and φE0), rETRmax and α were enhanced in response to NPs stress. However, OA promoted the growth and alleviated the adverse effects of NPs on P. donghaiense by increasing photochemical efficiency (φP0, ψ0, and φE0) and energy flux (RC/CS0, TR0/CS0, ET0/CS0) and enhancing the antioxidant ability (increased superoxide dismutase, and decreased MDA). P. donghaiense showed enhanced tolerance to NPs under simulated OA conditions. These findings enhance our knowledge of the HAB species response to NPs pollution under future OA scenarios.

中文翻译：

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海洋酸化通过调节光合性能增强了甲藻 Prorocentrum donghaiense 对纳米塑料诱导的氧化应激的耐受性


引言海洋酸化 （OA） 和纳米塑料 （NPs） 对有害藻华 （HAB） 的影响已成为全球主要关注的问题。然而，OA 和 NPs 对 HAB 物种的综合影响知之甚少。方法本研究以典型的HAB物种东海甲藻Prorocentrum donghaiense为研究对象，将其暴露于不同浓度的NPs（108.15 ± 8.52 nm）（0、5、10和15 mg L−1）和CO2（低CO2：417 ppm，pH：8.00和高CO2：1045 ppm，pH：7.73）中7 d，探讨OA和NPs的综合效应。 如丙二醛 （MDA） 含量升高和类胡萝卜素/叶绿素-a 比率降低所示，尽管光化学效率 （φP0 、ψ0 和 φE0） 、 rETRmax 和 α 响应 NPs 胁迫而增强。OA通过提高光化学效率（φP0、ψ0和φE0）和能量通量（RC/CS0、TR0/CS0、ET0/CS0）和增强抗氧化能力（增加超氧化物歧化酶和降低MDA）促进了NPs的生长并减轻了NPs对东海松的不利影响。东海松在模拟 OA 条件下对 NPs 的耐受性增强。这些发现增强了我们对未来 OA 情景下 HAB 物种对 NPs 污染的反应的了解。