Feedback mechanisms between ecosystem change, fish behaviour and metabolism

人们从加拿大淡水湖获得的生态系统服务，例如娱乐、捕鱼和灌溉，也会给我们提供这些服务的水生社区带来压力。这些影响可能相互作用，或以意想不到的方式与其他形式的背景压力(例如，气候变化)相互作用。准确衡量淡水生态系统如何应对压力，并清楚地了解特定压力因素对生态系统的作用方式(以及压力因素如何相互作用)，是实现这些重要生态系统长期可持续管理的关键步骤。更好地了解环境压力如何影响生态系统，以及水生生态系统可以承受的压力的数量和类型，将使政策制定者和资源管理者更好地保护我们的基本淡水资源，同时确保它们继续在快速变化的环境中提供我们享有的服务。 群落结构和生态系统功能之间的联系，或者能量在食物网中移动的速度和路径，仍然是生态学研究中一个研究较少的领域。然而，越来越清楚的是，在许多情况下，水生动物的行为可能有助于解释我们观察到的能量如何有效地从食物网的一个营养级别转移到下一个营养级别的一些差异。 我们的研究计划试图揭示水生动物群落的结构变化如何影响生态系统功能和能量途径。我们的最终目标是促进渔业生物学、食物网生态学、群落生态学和生物能量学领域的知识进步，并利用我们获得的信息为子孙后代改善我们淡水的可持续资源管理。 在我的NSERC发现资助计划的未来五年里，我将带领我的研究团队更清楚地阐明鱼类行为和新陈代谢对加拿大淡水湖能量转移率变化的贡献。我们将使用两种相辅相成的方法来实现这一目标。首先，我们将开发生态模型，以利用世界级IISD-实验湖地区淡水生物的大量长期数据和存档组织收集；这将使我们能够通过整个生态系统实验和气候变化，模拟几十年来鱼类的行为和新陈代谢，并使我们能够评估这些变化有多重要，以及它们可能如何相互作用，改变鱼类的行为和通过这些生态系统的能量流动。其次，我们将开发和开展一系列实验、比较实验室和野外生态学研究，以评估和确定不同湖泊之间鱼类行为的差异，并将这些变化与鱼类生长、密度、繁殖和死亡的生命速率联系起来。

The ecosystem services that people draw from freshwater lakes in Canadarecreation, fishing and irrigation, to name a fewcan also cause stress on the aquatic communities that we draw those services from. These impacts may interact with each other, or with other forms of background stress (e.g., climate change) in unexpected ways. Accurately measuring how freshwater ecosystems respond to stress, and clearly understanding the ways in which specific stress factors act on ecosystems (and how stressors interact with one another) are key steps towards the long-term sustainable management of these vital ecosystems. A better understanding of how environmental stress impacts ecosystems, and the amount and types of stress aquatic ecosystems can tolerate, will put policy makers and resource managers in a better position to protect our essential freshwater resources while ensuring that they continue to provide the services we enjoy in a rapidly changing environment. The link between community structure and ecosystem function, or how quickly and what path energy takes as it moves through the food webs, remains an understudied area of ecological research. It is however becoming clear that in many cases, the behaviour of aquatic animals may help to explain some of the variability we observe in how efficiently energy is transferred from one trophic level of the food web to the next. Our research program seeks to reveal how structural changes in aquatic animal communities affect ecosystem function and energetic pathways. Our ultimate goal is to advance knowledge in the fields of fisheries biology, food web ecology, community ecology and bioenergetics, and to use the information we gain to help improve sustainable resource management of our freshwaters for future generations. During the next five years of my NSERC Discovery Grant Program, I will lead my research group to more clearly illustrate the contribution of fish behaviour and metabolism to variation in energy transfer rates in Canadian freshwater lakes. We will address this objective using two complementary approaches. First, we will develop ecological models to take advantage of extensive long-term data and archived tissue collections of freshwater organisms from the world-class IISD-Experimental Lakes Area; this will allow us to model fish behaviour and metabolism over the course of decades through both whole ecosystem experiments and climate change, and will allow us to evaluate how important those changes are and how they may interact to alter fish behaviour and energy flow through these ecosystems. Second, we will develop and carry out a series of experimental and comparative lab and field-based ecological studies to evaluate and identify how fish behaviour differs among lakes that vary or change in specific ways, and relate those changes to vital rates of fish growth, density, reproduction and mortality.