SGER: Biomixing - a controversial mechanism influencing dynamics of marine ecosystems?

研究人员将研究“生物混合”现象——生物运动引起水柱混合的过程——通过结合两种新方法——一种正在发展的技术，独立水下测速仪（SCUVA），和一种正在发展的研究系统（海洋湖泊）。在小尺度上研究粒子速度和湍流的典型仪器——数字粒子图像测速仪（DPIV）——通常受到尺寸大、与表面的物理连接以及无法主动跟踪运动动物的限制。SCUVA是一种更轻便、自主的便携式DPIV设备，能够实时量化单个动物周围的流场。使用SCUVA，可以测量从0.002米到0.25米大小的水生动物-流体相互作用，从而将单个动物或水母群产生的湍流与整个水柱的中尺度涡旋混合结合起来，与已建立的声学多普勒电流计剖面仪技术同步测量。海洋湖泊是完全被陆地包围的海水体。它们是易于接近的中小型生态系统，可以在适度的规模和预算下进行全面研究。潮汐交换仅限于离散的海底隧道的湖泊也包含数十亿桡足类动物和数千万拳头到盘子大小的水母。因此潮汐混合、生物混合（通过微观和宏观浮游动物）和风混合都可以被量化，海洋湖泊可能为更广泛、更复杂的系统提供更简单的微观世界。研究人员将使用通用海洋湍流模型（GOTM）量化水母群的物理和生物混合的相对影响。更广泛的影响：该项目将有助于增加海洋学的多样性，继续培训一名帕劳女性海洋科学研究助理，并促进两名女性研究生的研究。帕劳的资源管理人员将利用GOTM进行模拟，以探索气候变化对“水母湖”生态系统的可能影响，气候变化直接由天气或间接由水母种群动态介导，水母湖是帕劳重要的生物多样性和经济资源。GOTM模型将适应探索不同的沿海情况，促进对海洋生物混合潜力的深入探索。

The investigators will study the phenomenon of "biomixing" - the process by which the movement of organisms cause the mixing of the water column - by bring together two novel approaches - a developing technology, Self-Contained Underwater Velocimetry Apparatus (SCUVA), and a developing study system (marine lakes). Typical instrumentation that study particle velocity and turbulence at small scales - digital particle image velocimetry (DPIV) - are typically limited by large size, physical connections to the surface, and inability to actively track moving animals. SCUVA is a less cumbersome, autonomous, portable DPIV equipment able to quantify the flow field surrounding individual animals in real-time. Using SCUVA, it is possible to measure aquatic animal-fluid interactions from 0.002 m to 0.25 m size and thus to integrate turbulence created by individual animals or swarms of medusae with mesoscale eddy mixing of the entire water-column measured synchronously with established Acoustic Doppler Current meter Profiler technology. Marine lakes are bodies of seawater entirely surrounded by land. They are easily accessible, small-to-medium sized ecosystems that can be studied comprehensively on a modest scale and budget. Lakes with tidal exchange limited to discrete submarine tunnels also contain billions of copepods and tens of millions of fist-to-plate sized jellyfish. Thus tidal mixing, biomixing (by micro- and macro-zooplankton), and wind-mixing can each be quantified, and marine lakes may provide simpler microcosms of more widespread, complex systems. The investigators will quantify the relative impact of physical and biological mixing by swarms of medusae using the General Ocean Turbulence Model (GOTM). Broader impacts: The project will contribute to increased diversity in the oceanography by continuing training of a female Palauan research assistant in marine science, and facilitating the research of two female graduate students. The simulation using GOTM will be employed by resource managers in Palau to explore possible impacts of changing climate, mediated directly by weather or indirectly by jellyfish population dynamics, on the "Jellyfish Lake" ecosystem which is an important biodiversity and economic resource in Palau. The GOTM model will be adaptable to explore diverse coastal situations, promoting thorough exploration of the potential of biomixing in the ocean.