Dynamics and functions of pelagic copepod communities in a changing Arctic Ocean.

提出的研究的长期目标是发展北极海洋生态系统数值模型的预测能力。目前，海洋生态系统所面临的变化加速，特别是在气候变暖对地球影响最大的北极地区，超过了海洋生态新知识的获取速度。然而，使用功能强大的计算机的现代方法可以为有效预测这些环境变化对海洋生态系统的影响提供手段。*这项研究将集中在浮游动物上。浮游动物是微生物和动物之间、浮游植物（单细胞植物）和来自更高营养层的捕食者（鱼、鲸、鸟）之间、接受太阳能量的薄薄的表层和黑暗寒冷的海洋深处之间必不可少的界面。桡足类是一组浮游动物，体现了这一关键作用。这些小甲壳类动物非常成功，它们实际上是地球上数量最多的动物。在北极，一些重要的桡足类物种形成了群落，是能量和物质转移的重要枢纽。桡足类动物将强烈而短暂的春季浮游植物繁殖转化为能量密集的生物质（脂质），可以在更长的时间内提供更高的营养水平。因此，桡足类动物在营养网络和碳、氮等重要元素的生物地球化学循环中都起着关键作用。**拟议的五年研究计划旨在探索北极桡足动物群落组织、运作和对环境强迫反应的机制。为了更好地理解，我和我的学生将遵循四个具体目标：*(1)当与其他物种隔离时，北极海洋生态系统中发现的桡足类物种的适应性如何应对各种环境条件*(2)群落中的种间相互作用如何改变第(1)点研究的物种特异性反应*(3)第(1)点和第(2)点研究的个体和种群水平过程如何扩大规模以形成稳定的桡足类*(4)桡足动物群落的变化如何影响北极海洋生态系统的营养转移**为了实现这些目标，我们将使用理论建模方法和应用加拿大海洋的生物物理区域3D模型相结合。这些模型将得到加拿大几十年来在北极的研究工作中收集到的大量观测数据的支持，这些观测数据将在即将进行的采样任务中获得，也将得到国际合作者的支持。*已经观察到北极海洋生态系统的重大变化，预计还会发生更多变化。数值模拟是一种强大的研究途径，可以帮助我们加强对这些高度专业化生态系统的机制理解。目前浮游动物群落的有效机制模型非常罕见，北极也不存在。在这项研究期间将开发的创新数值方法将使加拿大的研究保持在海洋生态学的前沿。它还将有助于解决紧迫的管理问题，如在北极开发新的渔业，根据加拿大的承诺或法律义务实施海洋保护区，或新型人为灾害（石油泄漏等）对北极海洋生态系统的影响。

The long-term goal of the proposed research is to develop the predictive capabilities of numerical models of Arctic marine ecosystems. The acquisition of new knowledge in marine ecology is currently outpaced by the acceleration of changes faced by marine ecosystems, particularly in the Arctic where the impacts of climate warming are the strongest on our planet. Yet, modern approaches using powerful computers can provide the means for effective forecasting of the impacts of these environmental changes on marine ecosystems. *This research will focus on zooplankton. Zooplankton is an essential interface between the microbes and animals, between the phytoplankton (unicellular plants) and the predators from the higher trophic levels (fishes, whales, birds.), between the thin surface layer receiving the sun's energy and the dark and cold ocean's depths. Copepods are a group of zooplankton that incarnates this critical role. These small crustaceans are so successful that they actually are the most numerous animals on Earth. In the Arctic, a handful of keystone copepod species form communities that are essential hubs of energy and matter transfer. Copepods transform the intense but short spring phytoplankton bloom into an energy-dense biomass (lipids) available for higher trophic levels during a much longer period of time. As a result copepods play a key role in both trophic networks and biogeochemical cycles of important elements such as carbon or nitrogen.**The proposed five-year research plan aims at exploring the mechanisms underpinning the Arctic copepod communities' organization, operation and response to environmental forcing. Students under my supervision and myself will follow four specific objectives in order to better understand:*(1) how the fitness of copepods from species found in Arctic marine ecosystems should respond to various environmental conditions when isolated from other species*(2) how inter-specific interactions in a community alter species-specific responses studied in point (1)*(3) how the individual and population-level processes studied in points (1) and (2) scale-up to shape stable copepod communities*(4) how changes in copepod communities influence trophic transfers in Arctic marine ecosystems**In order to achieve these objectives, we will use a combination of theoretical modelling approaches and applied bio-physical regional 3D models of the Canadian seas. The models will be supported by numerous observations collected during several tens of years of Canadian research efforts in the Arctic and acquired in upcoming sampling missions, as well as from international collaborators. *Major changes in Arctic marine ecosystems are already observed and more are expected to come. Numerical modelling is one powerful avenue of research that can help enhancing our mechanistic understanding of these highly specialized ecosystems. Efficient mechanistic models of zooplankton communities are currently very rare and none exist for the Arctic. The innovative numerical methods that will be developed during this research will keep Canadian research at the forefront of marine ecology. It will also help addressing pressing management issues such as the development of new fisheries in the Arctic, the implementation of marine reserves according to Canada's commitments or legal obligations, or the impacts of new kinds of anthropic hazards (oil spills among others) on Arctic marine ecosystems.