Sinking or floating is the natural state of planktonic organisms and particles in the ocean. Simulating these conditions is critical when making measurements, such as respirometry, because they allow the natural exchange of substrates and products between sinking particles and water flowing around them and prevent organisms that are accustomed to motion from changing their metabolism. We developed a rotating incubator, the RotoBOD (named after its capability to rotate and determine biological oxygen demand, BOD), that uniquely enables automated oxygen measurements in small volumes while keeping the samples in their natural state of suspension. This allows highly sensitive rate measurements of oxygen utilization and subsequent characterization of single particles or small planktonic organisms, such as copepods, jellyfish, or protists. As this approach is nondestructive, it can be combined with several further measurements during and after the incubation, such as stable isotope additions and molecular analyses. This makes the instrument useful for ecologists, biogeochemists, and potentially other user groups such as aquaculture facilities. Here, we present the technical background of our newly developed apparatus and provide examples of how it can be utilized to determine oxygen production and consumption in small organisms and particles.

中文翻译：

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RotoBOD─量化悬浮颗粒和生物体的耗氧量


下沉或漂浮是海洋中浮游生物和颗粒的自然状态。在进行呼吸测量等测量时，模拟这些条件至关重要，因为它们允许下沉颗粒和周围流动的水之间的底物和产物进行自然交换，并防止习惯运动的生物体改变其新陈代谢。我们开发了一种旋转培养箱 RotoBOD（以其旋转和确定生物需氧量 (BOD) 的能力而命名），它独特地能够自动测量小体积的氧气，同时保持样品处于自然悬浮状态。这样可以对氧气利用率进行高度灵敏的测量，并随后对单个颗粒或小型浮游生物（如桡足类、水母或原生生物）进行表征。由于这种方法是非破坏性的，因此可以与孵化期间和孵化后的一些进一步测量相结合，例如稳定同位素添加和分子分析。这使得该仪器对于生态学家、生物地球化学家以及水产养殖设施等潜在的其他用户群体非常有用。在这里，我们介绍了我们新开发的设备的技术背景，并提供了如何利用它来确定小生物和颗粒中氧气的产生和消耗的示例。