Collaborative Research - Connectivity of Bivalve Populations: Assessing Sources of Larval Recruits

合作研究 - 双壳类种群的连通性：评估幼虫新成员的来源

• 批准号: 0327209
• 负责人: Lisa Levin
• 金额: --
• 依托单位: University of California-San Diego Scripps Inst of Oceanography
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-10-01 至 2008-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0327209&HistoricalAwards=false
• 关键词: Collaborative; Research; Connectivity; Bivalve; Populations

The early life history of most marine benthic invertebrate organisms involves a planktonic larval stage of development that acts as an agent for increased dispersal and gene flow between sessile or sedentary adult populations. There remains considerable debate as to the spatial scale and strength of the connections between populations. This research project will examine connectivity of bivalve populations (defined as the extent to which a local population receives recruits from external sources), the role of physical transport, and the metapopulation consequences. Because larval stages are microscopic, it is all but impossible to follow individuals, or to track them with conventional tags. Technological advances have facilitated the use of trace element analysis to evaluate origins and trajectories of some planktonic larvae. Spatial variability in environmental, trace elemental characteristics of different coastal water masses is recorded in the geochemistry of biogenic carbonates. Because shells are deposited throughout planktonic larval development, they effectively record changes in environmental characteristics of different habitats occupied by larvae through development. Analysis of larval shell retained by newly settled bivalves will provide information about their source locations. Trace element fingerprinting methods will be used to evaluate the spatial scale and strength of connectivity among bivalve populations on the Massachusetts and southern California coasts. Hypotheses will address (1) the relative contribution of remote larval sources versus local ones (self seeding), (2) the relationship between circulation?driven dispersal potential and realized connectivity among bivalve populations and (3) the roles of species spawning period, planktonic period, and spatial separation of sites in determining probabilities of larval exchange. Our approach involves laser ablation inductively coupled plasma mass spectrometry (LA?ICPMS) to resolve spatial changes in larval shell composition that reflect recruit origins and temporal patterns of larval transport. We will work with the clam Mya arenaria and the mussel Mytilus edulis in New England and the mussels Mytilus galloprovincialis and M. californianus in southern California. Population connectivities will be studied with two metapopulation approaches that estimate dispersal probabilities from hydrodynamic models. One involves habitat area as a proxy for fecundity and the other is a multiregional matrix model that uses a demographic framework to describe the dynamics of the metapopulation. We will test realized population connectivity determined from trace elemental analysis of recruit origins against a priori predictions based on the circulation and metapopulation models.Broader impacts: The resulting information about source populations and connectivities will enhance understanding of metapopulation dynamics in commercially valuable bivalve species. Connectivity information applicable to the east and west coasts of the USA will facilitate conservation of coastal resources through the improved design of marine protected areas and fisheries regulations. Key educational elements include the involvement of undergraduate, graduate, and postdoctoral students, as well as early career scientists, in interdisciplinary research that integrates coastal ocean physics, larval ecology and metapopulation theory. There will be a transfer of trace element fingerprinting technology (from fish) into the realm of invertebrate dispersal and to collaborators in Mexico.[edited - JP - 7/7/03]

大多数海洋底栖无脊椎动物的早期生活史涉及浮游幼虫的发育阶段，该阶段充当增加无柄或静止成年种群之间的扩散和基因流动的媒介。关于人口之间联系的空间规模和强度仍然存在相当多的争论。该研究项目将研究双壳类种群的连通性（定义为当地种群从外部来源接收新成员的程度）、物理运输的作用以及集合种群的后果。 由于幼虫阶段是微观的，因此几乎不可能跟踪个体，或者用传统的标签来追踪它们。 技术进步促进了微量元素分析的使用，以评估一些浮游幼虫的起源和轨迹。 生物碳酸盐的地球化学记录了不同沿海水体的环境、微量元素特征的空间变异性。 由于贝壳是在浮游幼体发育过程中沉积的，因此它们有效地记录了幼体在发育过程中所占据的不同栖息地的环境特征的变化。 对新定居的双壳类保留的幼虫壳的分析将提供有关其来源位置的信息。 微量元素指纹识别方法将用于评估马萨诸塞州和南加州海岸双壳类种群之间的空间规模和连通性强度。假设将解决（1）远程幼体来源与本地幼体来源（自播种）的相对贡献，（2）循环驱动的扩散潜力与双壳类种群之间已实现的连通性之间的关系，以及（3）物种产卵期、浮游生物的作用确定幼虫交换概率的地点的周期和空间分离。我们的方法涉及激光烧蚀电感耦合等离子体质谱（LA？ICPMS）来解决幼虫壳成分的空间变化，这些变化反映了幼虫运输的新芽起源和时间模式。 我们将研究新英格兰的蛤蜊和贻贝以及南加州的贻贝。 将使用两种集合种群方法来研究种群连通性，这些方法根据流体动力学模型估计扩散概率。 一个涉及栖息地面积作为繁殖力的代理，另一个是多区域矩阵模型，使用人口统计框架来描述集合种群的动态。我们将根据基于循环和集合种群模型的先验预测，测试通过对招募来源的微量元素分析确定的已实现的种群连通性。更广泛的影响：由此产生的有关源种群和连通性的信息将增强对具有商业价值的双壳类物种的集合种群动态的理解。适用于美国东海岸和西海岸的连通性信息将通过改进海洋保护区和渔业法规的设计促进沿海资源的保护。关键的教育要素包括让本科生、研究生和博士后以及早期职业科学家参与整合沿海海洋物理学、幼虫生态学和复合种群理论的跨学科研究。 微量元素指纹技术（来自鱼类）将转移到无脊椎动物传播领域并转移给墨西哥的合作者。[已编辑 - JP - 7/7/03]