Ecological processes influencing zooplankton productivity in highly dynamic estuarine transition zones

河口过渡带是淡水和咸水的混合物，是全世界整个河流系统的关键过渡带。这些生态系统在生物生产力方面具有很高的生态价值，而生物生产力受河口再循环、潮汐混合和淡水排放等物理特性的强烈驱动。圣劳伦斯河口过渡带是甲壳类动物和重要商业鱼类的重要保留区和育雏区。高能量、复杂的河口生态系统的高生产力和时空异质性使其成为研究生境互联性对营养关系和生物过程影响的理想场所。即使认识到种群和群落动态受营养相互作用和被动和主动运输过程的调节，这些过程决定了环境空间复杂性和互联性（例如，资源的分散，生物的迁移），但这些过程在河口的整体生态系统意义仍未得到很好的理解。我的研究计划的目标是通过考虑种内遗传多样性，营养动力学和河口海景离散栖息地之间的连通性来了解次级（浮游动物）生产力的控制机制。我的目标是显著提高我们对浮游动物次级生产力模式的科学理解，因为这方面的知识对海洋资源的保护和可持续利用以及基于生态系统的管理方法中的生态系统健康至关重要。同时，这些知识对于补充我们对从初级生产到三级营养水平的营养转换的理解是必不可少的，因为浮游动物通常代表上层营养水平（例如鱼类）的营养基础。我们将重点关注最重要的河口物种，如桡足类、虫类和鱼类幼虫。我们将确定在整个河口过渡带中，泛黄齿茅次生产量的时空变异性与遗传多样性和营养相互作用之间的联系。我们将估计亲和蠓枝与流动消费者（蝇蛆、鱼类幼虫）之间的营养相互作用程度。结果表明，亲和鲈进化枝的生产力和营养联系的强度可能有助于预测这一重要苗区的幼鱼招募。这对重新引进的条纹鲈鱼的管理具有重要意义。

Estuarine transition zones, were freshwater mixes with saltwater, are critical ecotones for entire river systems worldwide. These ecosystems have a high ecological value in terms of biological productivity which is strongly driven by physical properties such as estuarine re-circulation, tidal mixing and freshwater discharge. The St. Lawrence estuarine transition zone represents important retention and nursery zones for crustaceans and commercially important fishes. The high productivity and spatiotemporal heterogeneity of this highly energetic and complex estuarine ecosystem makes it an ideal site to study the influence of habitat interconnectivity on trophic relationships and biological processes. Even if it is recognized that population and community dynamics are regulated by trophic interactions and passive and active transport processes that determine environmental spatial complexity and interconnectivity (e.g., dispersion of resources, migration of organisms), the overall ecosystem significance of these processes in estuaries is not well understood. The objective of my research program is to understand the control mechanisms of secondary (zooplankton) productivity by considering intraspecific genetic diversity, trophodynamics and the degree of connectivity among discrete habitats of the estuarine seascape. I aim to significantly advancing our scientific comprehension of zooplankton secondary productivity patterns, as this knowledge is of crucial relevance to the conservation and sustainable utilization of marine resources and ecosystem health in an ecosystem-based management approach. At the same time, this knowledge is essential to complement our understanding of the trophic turnover from primary production to tertiary trophic levels, as zooplankton often represents the nutritional basis for upper trophic levels (e.g. fish). We will focuss on the most important estuarine species, such as copepods, mysids and fish larvae. We will determine links between the temporal and spatial variability in Eurytemora affinis secondary production, and genetic diversity and trophic interactions throughout the estuarine transition zone. We will estimate the degree of trophic interactions between E. affinis clades and mobile consumers (mysids, fish larvae). Results on E. affinis clade productivity and the strength of trophic linkages may help predicting larval fish recruitment in this important nursery zone. This will be of importance for the management of the re-introduced striped bass.