ABSTRACT: It is important to understand how planktonic dinoflagellate movements may be affected by environmental conditions, including those potentially influenced by climate change. Because of their small size, dinoflagellates can be expected to be highly sensitive to changes in viscosity; however, there is currently little understanding of how these organisms and other algae may be regulated by seawater viscosity. Previous work that has addressed the effects of seawater viscosity on single-celled plankton considered unnaturally large viscosity changes from a biomechanical perspective, sometimes without considering temperature effects. We studied the swimming of the dinoflagellate Prorocentrum minimum, a common coastal species, when exposed to environmentally relevant temperature and viscosity changes. P. minimum showed an additive response to seawater viscosity and temperature: cold temperature and high viscosity both slowed swimming speeds. However, seawater temperature and viscosity did not affect the movement direction or linearity of swimming of the dinoflagellates. We argue that temperature-related changes in movement may be partially regulated by a mechanical response to viscosity, which increases at cold temperature. We also propose possible future directions for laboratory and modelling studies.

中文翻译：

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海水粘度和温度对海洋鞭毛藻原圆极小运动的影响。

摘要：重要的是要了解浮游性鞭毛虫运动可能受到环境条件的影响，包括那些可能受到气候变化影响的条件。由于小鞭毛的尺寸小，可以预期它们对粘度的变化高度敏感。然而，目前对如何通过海水粘度调节这些生物和其他藻类知之甚少。以前解决海水粘度对单细胞浮游生物影响的工作从生物力学的角度考虑了不自然的大粘度变化，有时没有考虑温度影响。当暴露于环境相关的温度和粘度变化时，我们研究了鞭毛最低原鞭毛体（一种常见的沿海物种）的游动。最小体育疫霉显示出对海水粘度和温度的累加响应：低温和高粘度都降低了游泳速度。但是，海水温度和粘度不会影响藻鞭藻的运动方向或游动线性。我们认为，与温度相关的运动变化可能部分受到对粘度的机械响应的调节，该响应在低温下会增加。我们还为实验室和模型研究提出了可能的未来方向。