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

供给侧生态突出了大规模物理-海洋过程在决定招聘成功方面的作用。虽然大范围的水流，如上升流、热锋、潮汐洞穴和风暴，可以偶尔使幼虫沐浴在海岸线上，但它们并不完全是幼虫供应和定居的局部变化的原因。这些较小尺度的分布部分是由于浮游幼虫行为和流动状态之间的相互作用。不再被认为是严格与实验室静水条件相关的新奇事物，水性化学线索在一系列水动力制度和分类群上作为幼虫定居的原因越来越明显。然而，由于技术的限制，以前的研究只证明了溶解的信号分子对行为或沉降的潜在能力。它们既没有为更大范围的生态效应提供机制基础，也没有实现实验环境和自然环境中溶解化学环境之间的动态相似性。因此，关于水基化合物的运输、幼虫的行为反应和流态动态之间的相互作用，还没有一个综合的理论出现。这项研究项目探索了化学信号分子在一个非凡的生物系统中的生态相关性，在这个系统中，不同的线索类型和幼虫的发育形态发生在单一物种和栖息地内。此外，应用新的研究方法克服了幼虫聚落研究中的许多经典绊脚石。对自然线索使用可靠的化学标记，对流动水域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释放，将促进水槽和现场研究，这些研究将根据化学和物理状况进行动态缩放。这项研究首先涉及对溶解线索浓度和流动变量中自然出现的范围进行现场测量。其次，水槽研究量化了幼虫对水上线索的行为反应，并分别和联合测试了两种线索类型(水上和表面吸附)对定居的影响。这些研究建立在第三个，也是最具生态意义的研究组成部分--野外实验操作上，旨在解决溶解与吸附线索如何决定幼虫在自然界中的分布。这项研究将水柱中小尺度作用的机制与床上的沉降、被动迁移与主动行为、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别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，研究生和本科生将受到激励，在他们成长为年轻科学家的过程中，跨越学科界限，拥抱新技术。来自代表性不足群体的学生将通过加州大学洛杉矶分校和加州大学洛杉矶分校的CEA-CREST中心的CARE和LEADS项目就业，并将鼓励他们参与水槽和实地工作。此外，该项目将促进一所授予博士学位的机构(UCLA)的两名教授和一所主要本科大学(CSULA)的一名新教员之间的合作，该大学有84%的少数民族入学率。

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.