Relative Influence of Turbulence and Waves on Larval Behavior

本研究将探讨蜗牛幼虫从不同的栖息地如何响应湍流和表面重力波的流体力学线索。 湍流和波浪是海岸流的共同特征，并可能为幼虫提供行为线索，帮助运输到特定的流态或栖息地。湍流导致一些软体动物幼虫下沉更频繁，但仍然未知的检测机制和波的反应。 Laravel可以感知空间速度梯度（应变率和涡度）或加速度。 湍流和波浪对小尺度流动的影响不同;湍流可以产生更大的应变率和涡度，而波浪可以产生更大的加速度。 感测多个流动特征的laraerodynamics可能能够区分以潮汐为主的沿海海湾和以波浪为主的大陆架区域。 在这项研究中，幼虫的行为将在几个设备，产生稳定的应变率和涡度，简单的加速度，均匀的湍流，和复杂的流与湍流加波量化。 数据将被用来开发随机模型的幼虫行为作为流体力学的功能，并测试有关生态和基于大小的控制behavior.Intellectual优点的假设：拟议的研究解决了以下基本方面的幼虫行为和生态影响的湍流和波浪：1）新的方法来获得洞察力的行为信号。 两相红外粒子图像测速技术将被应用于多个流动池中，以研究湍流和波浪在幼虫尺度上的影响。 将开发统计协议，用于将行为观察转化为经验模型，为更复杂的行为与物理循环模型的仔细整合奠定基础。 研究结果将确定影响潮间带和陆架栖息地物种行为的关键流体特征。2）波浪对行为的影响。 许多栖息地的影响，甚至占主导地位的波浪，但迄今为止还没有研究探讨波浪提供幼虫的行为信号的潜力。这项研究将是第一个探索幼虫对只存在于波浪中的大加速度的反应。3）行为在扩散中的作用。 底栖动物补充变异性的部分原因是由于幼体对物理环境的反应而造成的扩散的变幻莫测。 湍流和波浪在空间和时间上都因层化、水深、潮汐和风而变化。 湍流和波浪的小规模症状可能会引起幼虫的行为，有助于分散轨迹的差异。本研究将描述幼虫对流体力学线索的反应，最终可以解释扩散和招募的不确定性。4）适应物理环境。 剪切和加速度是潜在的行为信号，可能会被人类的影响，如划船，海岸线改造或风暴增强或减弱。 如果行为被调整到特定的流动状态，幼虫可能难以适应不断变化的海洋环境。 这项工作将有助于评估变化的物理过程对幼虫行为和dispersion.Broader影响的潜在生态影响：拟议的研究整合生态学，海洋物理学和最先进的技术，以促进跨学科的研究，教学和基础设施。 Co-PI Gerbi是一名博士后助理，他的职业生涯将受益于高度跨学科项目的指导和经验。 一名研究生将做论文研究，同时获得海洋生态学，流体力学和流量测量技术的专业知识。 两名本科生将被招募参加通过NSF RIOS计划和罗格斯大学的少数民族学生阿雷斯蒂计划，罗格斯大学的学生将做这个项目的一部分高级论文。 这项研究的结果将被纳入一个新的课程，在生物物理相互作用的研究生和本科生。 该项目提供了几个机会，以改善和扩大幼虫动物园，一个网络档案，提供电影的游泳幼虫，以广大观众。 PIV和流量罐将完成一个新的浮游生物-流体相互作用实验室，利用罗格斯大学的重大贡献。 PIV是罗格斯大学海水水槽设施流量测量能力的宝贵升级。

This study will investigate how snail larvae from distinct habitats respond to fluid-mechanical cues in turbulence and surface gravity waves. Turbulence and waves are common features of coastal flows and may provide larvae with behavior cues that aid transport toward specific flow regimes or habitats. Turbulence induces some mollusk larvae to sink more frequently, but still unknown are the detection mechanism and the response to waves. Larvae may sense spatial velocity gradients (strain rate and vorticity) or acceleration. Larval-scale flows are affected differently by turbulence and waves; turbulence can generate larger strain rates and vorticity whereas waves can generate larger accelerations. Larvae that sense multiple flow characteristics may be able to distinguish between turbulence-dominated coastal embayments and wave-dominated regions of the continental shelf. In this study, larval behaviors will be quantified in several devices that generate steady strain rates and vorticity, simple acceleration, homogeneous turbulence, and complex flow with turbulence plus waves. Data will be used to develop stochastic models of larval behavior as a function of hydrodynamics and to test hypotheses about ecological and size-based controls on behavior.Intellectual Merit: The proposed research addresses the following fundamental aspects of larval behavior and the ecological impacts of turbulence and waves:1) Novel approaches to gain insights on behavioral signaling. Two-phase infrared particle-image velocimetry techniques will be applied in multiple flow tanks to study effects of both turbulence and waves at the scale of larvae. Statistical protocols will be developed for converting behavior observations into empirical models, laying the groundwork for careful integration of more complex behaviors with physical circulation models. Results will identify the key fluid characteristics affecting behavior in species from intertidal and shelf habitats.2) Impact of waves on behavior. Many habitats are influenced or even dominated by waves, yet no study to date has explored the potential for waves to provide a larval behavioral signal. This study will be the first to explore larval response to the large accelerations present only in waves.3) Role of behavior in dispersal. Benthic recruitment variability arises partly from vagaries of dispersal that result from larval responses to the physical environment. Turbulence and waves vary spatially and also temporally due to stratification, water depth, tides, and winds. Small-scale symptoms of turbulence and waves could elicit larval behaviors that contribute to differences in dispersal trajectories. This study will describe larval responses to hydromechanical cues that ultimately could explain uncertainty in dispersal and recruitment.4) Adaptation to physical environments. Shears and acceleration are potential behavior signals that could be enhanced or dampened by human impacts such as boating, shoreline modification, or storms. If behaviors are tuned to specific flow regimes, larvae may have difficulty adapting to changing marine environments. This work will be instrumental in assessing potential ecological impacts of changing physical processes on larval behavior and dispersal.Broader Impacts: The proposed study integrates ecology, ocean physics, and state-of-the-art technology to promote interdisciplinary research, teaching, and infrastructure. Co-PI Gerbi is a postdoctoral associate, and his career will benefit from mentoring and experience on a highly interdisciplinary project. One graduate student will do dissertation research while gaining expertise in marine ecology, fluid mechanics, and flow-measurement technology. Two undergraduates will be recruited to participate through the NSF RIOS program and the Rutgers Aresty program for minority students, and the Rutgers student will do a senior thesis on part of this project. Results of this research will be incorporated into a new course in biological-physical interactions for graduate and undergraduate students. The project offers several opportunities to improve and expand the Larval Zoo, a web archive that provides movies of swimming larvae to a wide audience. The PIV and flow tanks will complete a new Plankton-Fluid Interactions Laboratory, leveraging a substantial contribution from Rutgers. The PIV is an invaluable upgrade to the flow-measurement capabilities of the Rutgers seawater flume facility.