Collaborative research: Nearshore larval transport: physical and biological processes

为这项研究提供奖项将提供管理沿海资源所需的基本知识。本研究探讨了近岸跨岸幼虫的运输过程，即通过波浪环流/斯托克斯漂移和内部潮汐孔进行的幼虫运输。通过波浪环流/Stokes漂移进行幼虫的运输是一个普遍存在的过程，还没有被观测到的研究，也不知道内潮孔如何将幼虫运送到潮间带生境。该项目将研究近岸(20米水深和潮间带之间的区域)将幼虫运送到成虫栖息地的物理和生物过程。南加州的研究系统与大多数其他温带地区有相似之处，我们将研究广泛分布并在各种环境中成功的海洋类群。智力上的优点：最近的研究表明，近岸地带的幼虫运输在幼虫扩散和浅水物种的连通性中发挥着核心作用。然而，这些最近的进展并没有与在适当的时间和空间尺度上处理环流和行为过程的面向过程的研究相匹配，并且只考虑了近岸开阔海岸线的少数幼虫运输机制。然而，在我们对驱动跨岸流动的水动力过程的理解方面的最新进展，以及对这些过程对幼虫运输重要性的日益认识，使得这项研究变得及时。研究人员推测，一系列的物理和生物事件导致无脊椎动物幼虫被运送到潮间带栖息地。这些事件包括由于近水面的波浪循环/斯托克斯漂移和接近底部的内部潮汐循环所造成的物理传输，末期幼虫阶段行为的改变，以及幼虫利用“适应性”行为反应来利用事件相关流。此外，它们还表明，波浪环流/斯托克斯漂移和内部潮汐环流的优势随季节变化，其中内潮孔在水柱分层良好的春夏季很重要，而波浪环流/斯托克斯漂移在秋季/冬季更为普遍，恰逢冬季风暴。这项研究中的假设将通过对物理运输、幼虫供应和定居的估计来检验。这些测量结果将与自适应采样相结合，以测试幼虫垂直分布对水动力条件变化的依赖性。广泛影响：这项研究的结果将具有重要的生态影响，因为波浪环流/斯托克斯漂移和内部运动可能是海洋生物幼虫的关键和常规传输机制，这些幼虫必须返回近岸生境才能完成其生命周期，从而影响沿海规划者使用的种群连通性和管理战略(例如基于生态系统的渔业管理、海洋保护区的安置)。调查人员将通过讲座和开发网站向公众传播他们的结果。此外，该项目有很强的教育内容，涉及两个机构(世界卫生组织和圣地亚哥大学)的本科生和/或研究生。这项研究将被整合到各自机构的所有合作个人教授的课程中，但这项研究的一个组成部分是通过在大学(一所文科大学)的尖端研究经验来加强学生的体验式学习。作为这一项目的一部分，采样将被纳入一门面向高年级本科生的野外海洋群落生态学课程，学生将被要求参加至少一次研究巡航。调查人员还计划为加州大学的暑期研究提供有竞争力的本科生津贴。为了传播研究成果，与会者将被要求参加一年一度的本科生研究会议，以突出在大学举行的学生与教师之间的互动。

Providing an award for this study will provide essential knowledge required for management of coastal resources. This study addresses near shore cross-shore larval transport processes that operate over wide geographic areas in open coast settings, namely larval transport by wave circulation / Stokes drift, and by internal tidal bores. Larval transport by wave circulation / Stokes drift is a ubiquitous process that has not been studied observationally, and it is not known how internal tidal bores deliver larvae to intertidal habitats. This project will examine near shore (region between 20 m depth and intertidal) physical and biological processes that account for the delivery of larvae to adult habitats. The study system in Southern California shares similarities with most other temperate areas and we will study marine taxa that are widely distributed and successful in a variety of environments.Intellectual Merit: Recent studies suggest that larval transport in the near shore zone plays a central role in larval dispersal and connectivity of shallow water species. These recent advances, however, have not been matched with process-oriented studies addressing circulation and behavioral processes at the appropriate temporal and spatial scales, and only a few larval transport mechanisms have been considered for near shore open coastlines. Recent advances in our understanding of hydrodynamic processes driving cross-shore flows and growing awareness of the importance of the processes to larval transport, however, make this study timely. The investigators hypothesize that a series of physical and biological events results in the delivery of invertebrate larvae to the intertidal habitat. These events include physical transport due to wave circulation / Stokes drift near the surface and internal tide circulation near the bottom, alteration of behavior for terminal larval stages, and larval use of "adaptive" behavioral responses to exploit event-dependent flows. Further, they suggest that the predominance of wave circulation / Stokes drift and internal tide circulation varies seasonally, with internal tidal bores important in spring/summer, when the water column is well-stratified, and wave circulation / Stokes drift more pervasive in fall/winter, coinciding with winter storms. The hypotheses in this study will be tested with estimates of physical transport, larval supply and settlement. These measurements will be combined with use of adaptive sampling to test the dependence of larval vertical distribution on changes in hydrodynamic conditions.Broader Impacts: Results from this study will have important ecological implications as wave circulation / Stokes drift and internal motions may represent critical and regular transport mechanisms for larvae of marine organisms that must return to near shore habitats to complete their life cycle, thereby impacting population connectivity and management strategies used by coastal planners (e.g., ecosystem-based fisheries management, placement of Marine Protected Areas). The investigators will disseminate their results to the public through lectures and the development of a website. Furthermore, this project has a strong educational component, involving undergraduate and/or graduate students from two institutions (WHOI and University of San Diego). The research will be integrated into courses taught by all co-PIs at their respective institutions, but an integral component of this research is to enhance student experiential learning with cutting-edge research experiences at USD (a liberal-arts university). Sampling as part of this project will be incorporated into a field-based Marine Community Ecology course for upper-division undergraduates and students will be required to participate in at least one research cruise. The investigators also plan to offer competitive undergraduate student stipends for summer research at USD. To disseminate results, participants will be required to participate in the annual Undergraduate Research Conference, highlighting student-faculty interactions held at USD.