Collaborative Research: Larval behavior and supply-side ecology: Consequences of dissolved verus adsorbed chemical cues

供给侧生态学强调了大规模物理-海洋学过程在决定招聘成功方面的作用。虽然大规模的流动，如上升流、热锋、潮孔和风暴，可能会偶然地使幼虫沐浴在海岸线上，但它们并不完全负责幼虫供应和定居的局部变化。这些较小规模的分布部分是由于浮游幼虫的行为和水流状态之间的相互作用。不再被认为是与实验室静水条件严格相关的新奇事物，水生化学线索在一系列水动力制度和分类群中作为幼虫定居的致病因素越来越明显。然而，由于技术的限制，以前的研究只证明了溶解信号分子对行为或沉降的潜在能力。它们既没有为更广泛的生态效应提供机制基础，也没有在实验和自然野外环境中实现溶解化学环境的动态相似性。因此，关于水生化合物的运输、幼虫的行为反应和流动机制之间的相互作用的综合理论尚未出现。本研究项目探讨了一个显著的生物系统中化学信号分子的生态相关性，其中不同的线索类型和幼虫发育形态发生在单一物种和栖息地中。此外，采用新颖的研究方法，克服了幼虫沉降研究中的许多经典障碍。使用可靠的自然线索化学标记，对移动水中的幼虫进行计算机/视频成像的非侵入性方法，以及从聚合物凝胶中控制线索的释放，将促进水槽和现场研究，从而根据化学和物理制度进行动态缩放。研究包括，首先，现场测量自然发生的溶解线索浓度范围和流量变量。其次，水槽研究量化了幼虫对水生线索的行为反应，并实验测试了两种线索（水生和表面吸附）分别和共同对沉降的影响。这些研究建立在第三个，最具生态意义的研究组成部分，实地实验操作旨在解决如何溶解与吸附线索决定了自然界中幼鱼的分布。本研究将水柱内的小尺度作用机制与河床沉降、被动输运与主动行为、化学生态学与水动力学联系起来。这项工作将有助于填补相对大规模的供应侧过程和个人规模的床层勘探之间的空白。鉴于这项研究的高度跨学科性质，将鼓励研究生和本科生在发展成为年轻科学家的过程中跨越学科界限，接受新技术。来自弱势群体的学生将通过加州大学洛杉矶分校的CARE和LEADS项目以及CSULA的CEA-CREST中心被雇用，他们将被鼓励参与水槽和实地工作。此外，该项目将促进博士学位授予机构（加州大学洛杉矶分校）的两位教授和一所主要本科大学（CSULA）的一位新教员之间的合作，该大学有84%的少数族裔学生。

Supply-side ecology has punctuated the role of large-scale physical-oceanographic processes in determining recruitment success. Although large-scale flows, such as upwelling, thermal fronts, tidal bores, and storms, could episodically bathe the shoreline with larvae, they are not entirely responsible for localized variations in larval supply and settlement. These smaller-scale distributions are due, in part, to interactions between planktonic larval behaviors and the flow regime. No longer considered a novelty associated strictly with laboratory still-water conditions, waterborne chemical cues have growing visibility as causative factors in larval settlement over a range of hydrodynamic regimes and taxa. Because of technology limitations, however, previous studies have demonstrated only the potential capacities of dissolved signal molecules on behavior or settlement. They have neither provided a mechanistic basis for broader-scale ecological effects nor achieved dynamic similarity between dissolved chemical environments of experimental and natural field settings. A synthetic theory is therefore yet to emerge on interactions between the transport of waterborne compounds, behavioral responses of the larvae, and dynamics of the flow regime. This research project explores the ecological relevance of chemical signal molecules in a remarkable biological system, where alternative cue types and larval developmental morphs occur within a single species and habitat. Moreover, novel research methods are applied to overcome many classic stumbling blocks in larval-settlement research. Use of reliable chemical markers for the natural cue, non-invasive methods for computer/video imaging larvae in moving water, and controlled cue release from a polymer gel will facilitate flume and field research that is dynamically scaled for both the chemical and physical regimes. The research involves, first, field measurements of the naturally occurring ranges in dissolved cue concentrations and flow variables. Second, flume studies quantify behavioral responses of larvae to the waterborne cue, and test experimentally effects of the two cue types (waterborne and surface-adsorbed), separately and together, on settlement. These studies build toward the third, most ecologically meaningful research component, field experimental manipulations aimed at resolving how dissolved versus adsorbed cues determine juvenile distributions in nature. This research links mechanisms acting at small scales in the water column with settlement on the bed, passive transport with active behavior, and chemical ecology with hydrodynamics. The work will help fill the gap between relatively large-scale supply-side processes and individual-scale exploration of the bed. Given the highly interdisciplinary nature of this research, graduate and undergraduate students will be stimulated to cross disciplinary lines and embrace new technology as they develop into young scientists. Students from underrepresented groups will be employed through the CARE and LEADS Programs at UCLA and the CEA-CREST center at CSULA, and they will be encouraged to participate in both flume and field work. Further, this project will foster collaboration among two professors at a Ph.D.-granting institution (UCLA) and a new faculty member at a principally undergraduate university (CSULA), having 84% minority enrollment.