Collaborative Research: Numerical Study of the Unsteady Feeding Currents in Calanoid Copepods

合作研究：桡足类不稳定进食流的数值研究

• 批准号: 0352284
• 负责人: Houshuo Jiang
• 金额: $ 19.29万
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-05-01 至 2007-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0352284&HistoricalAwards=false
• 关键词: Collaborative; Research; Numerical; Study; Unsteady

Numerical Study of the Unsteady Feeding Current in Calanoid Copepods This research project will address the question, "Why are there two temporal types of generating feeding currents among herbivorous calanoid copepods"? That is, why do animals show an on/off pattern, creating an unsteady flow, when they have to overcome the inertia of the surrounding water every time they start moving? The investigators will first directly observe feeding animals in situ. Then, they will observe them in 3D in the laboratory to define (1) the structures of the feeding currents, and (2), the temporal patterns under different food regimes. The database, which includes the shapes and sizes of the animals observed, will be used for simulations using computational fluid dynamics (CFD). The research team consists of an applied mathematician/environmental fluid dynamicist (Jiang, WHOI), a biological oceanographer (Paffenhofer, SKIO), and two experimental marine biologists (Strickler and Janssen, UWM). Experiments will be conducted during a two-week stay at the Wrigley Marine Science Center where we will observe Calanus pacificus and Rhincalanus nasutus in situ and in the laboratory. The results will be data on the frequencies of switching the feeding current on/off, and on the structures and temporal changes of the water flow around the animals. The investigators will also study the activity patterns of calanoid copepods from the ocean off Savannah, GA, under different food densities. All the data sets generated will be constantly used to design the simulations in CFD at WHOI. The investigators expect to find evidence that there exist different survival strategies among calanoid copepods living in nutritionally dilute environments. The strategy to alternate the generation of a feeding current may be based on a compromise between low excess weight, large body size, and low food concentrations. This would contrast to the strategy of high excess weight, constant feeding current, large sensing range, and moderate food density. Intellectual Merits Planktonic copepods live in environments of varying and often severely limiting food abundances. So far few if any studies have addressed the adaptations of copepod behavioral repertoires to this diminished food availability. This study is designed to improve our understanding of copepod feeding behavior by studying empirically free-swimming calanoids, which produce unsteady on/off feeding currents of different kinds, and then compare the newly gained results with our knowledge to date about the steady feeding currents. Broader Impact The project will support the research efforts of a young, physically oriented scientist in a well-integrated interdisciplinary study with three accomplished senior biological ocean scientists. The PIs well-visited web sites on zooplankton ecology, marine and fresh-water, will serve to stimulate young persons to pursue the natural sciences. The investigators will disseminate the results in the scientific literature. Two undergraduate students will be working at Skidaway with G. -A. Paffenhofer and will interact with the team of PIs during the course of the project. .

对Calanoid copepods中不稳定喂养电流的数值研究该研究项目将解决以下问题：“为什么在草食性的calanoid copepods中会产生两种时间类型”？ 也就是说，为什么动物在每次开始移动时都必须克服周围水的惯性时会表现出一个不稳定的流程？研究人员将首先直接观察原位喂养动物。然后，他们将在实验室中的3D观察它们，以定义（1）进食电流的结构，以及（2），在不同的食物体系下的时间模式。包括观察到的动物的形状和大小的数据库将用于使用计算流体动力学（CFD）进行模拟。 研究小组由一名应用数学家/环境流体动力学家（Jiang，Whoi），一名生物海洋学家（Paffenhofer，Skio）和两名实验海洋生物学家（Strickler和Janssen，UWM）组成。实验将在箭牌海洋科学中心两周内进行，我们将在那里观察Pacificus和Rhincalanus Nasutus intu和实验室。结果将是有关关闭进食电流的频率的数据，以及动物周围水流的结构和时间变化。研究人员还将在不同的食物密度下研究乔治亚州萨凡纳（Savannah）萨凡纳（Savannah）海洋中的钙烷类co的活动模式。生成的所有数据集将不断用于在WHOI上在CFD中设计模拟。研究人员希望发现证据表明，生活在营养稀释环境中的钙碱类cop脚架之间存在不同的生存策略。交替产生喂养电流的策略可能是基于低体重，大体型和低食物浓度之间的妥协。这将与高度高过量，持续的喂养电流，大传感范围和中等食物密度的策略形成鲜明对比。智力优点浮游生物copepods生活在不同且经常严重限制食物丰富的环境中。到目前为止，很少有研究涉及copepod行为库的适应，以减少食物的可用性。这项研究旨在通过研究凭经验自由迅速的胆碱化来提高我们对CopePod喂养行为的理解，这些胆碱体产生不同种类的不稳定的内/关闭喂养电流，然后将新获得的结果与我们的知识进行比较，以了解有关稳定喂养电流的知识。该项目的更广泛的影响将支持一位年轻的，身体为导向的科学家的研究工作，并在一项良好的跨学科研究中与三位有成就的高级生物海洋科学家进行了整合。 PIS在浮游生物，海洋和淡水上经过良好访问的网站将刺激年轻人追求自然科学。 研究人员将在科学文献中传播结果。两名本科生将与G. -a一起在Skidaway工作。 Paffenhofer，将在项目过程中与PIS团队进行互动。 。