ABSTRACT: Abrupt changes in environmental conditions in estuaries and coastal waters have direct (physiological) and indirect (through changes in water column stability) effects on planktonic microalgae. Understanding and quantifying these effects is important to improve harmful algal bloom predictive models. Dinophysis spp. (D. acuminata, D. acuta and D. caudata) and Alexandrium minutum produce toxins that are transferred through the food web (particulate) by filter feeders and also released in the seawater. These dinoflagellates cause lengthy harvesting bans in European aquaculture sites and affect marine life. The 4 species were exposed to different combinations of temperature (T) and salinity (S) to investigate their short-term response (days) to and their recovery (weeks) from T/S stress. Dinophysis species showed varying capacities to deal with sudden changes in S, from the most resilient D. acuminata, equally affected by T and S stress, to the less tolerant D. acuta, and in particular D. caudata, more affected by S than T stress. The euryhaline A. minutum thrived under all the T/S combinations assayed. Further experiments showed a similar rate of okadaic acid toxin production (pg cell^-1 d^-1) for the 3 Dinophysis species under different T/S conditions. In contrast, a significant increment of gonyautoxin 4 content per cell was observed in A. minutum with decreasing S without significant effects associated with T. Our results highlight the response to environmental (T/S) stress of 3 species of Dinophysis and A. minutum with specific adaptations to thrive in different sub-habitats of the Galician Rías, an estuarine/coastal upwelling system in NW Spain.

中文翻译：

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温度和盐度胁迫对 Dinophysis spp. 生理学的相互作用。和 Alexandrium minutum：对生态位范围和开花模式的影响

摘要：河口和沿海水域环境条件的突然变化对浮游微藻有直接（生理）和间接（通过水柱稳定性的变化）影响。了解和量化这些影响对于改进有害藻华预测模型非常重要。龙藻属 （D. acuminata、D. acuta和D. caudata）和Alexandrium minutum产生的毒素由滤食动物通过食物网（微粒）转移，并释放到海水中。这些甲藻导致欧洲水产养殖场长期禁止捕捞，并影响海洋生物。这 4 个物种暴露于不同的温度 (T) 和盐度 (S) 组合，以研究它们对 T/S 胁迫的短期反应（天）和恢复（周）。Dinophysis物种表现出不同的能力来应对 S 的突然变化，从最具弹性的D. acuminata，同样受到 T 和 S 胁迫的影响，到耐受性较差的D. acuta，特别是D. caudata，受 S 的影响大于 T压力。广盐性A. minutum在测定的所有 T/S 组合下都茁壮成长。进一步的实验表明，在不同的 T/S 条件下，3 种龙藻类的冈田酸毒素产生率（pg 细胞^-1 d ^{-1 ）相似。}相比之下，在A. minutum中观察到每个细胞的 gonyautoxin 4 含量显着增加，S 减少而与 T 没有显着影响。我们的结果突出了 3 种Dinophysis和A. minutum对环境 (T/S) 胁迫的反应具有特定的适应性，可以在西班牙西北部的河口/沿海上升流系统 Galician Rías 的不同亚生境中茁壮成长。