Functional ecology of plankton: linking lake physical regimes, communities and ecosystem processes

现代生态学研究的一个主要目标是提高我们预测内在复杂系统对未来变化的反应的能力。在一个包括气候变暖在内的快速变化的时代，发展这种预测能力的紧迫性更加重要，这样我们就可以利用当前和前瞻性的知识来管理自然生态系统。在湖泊中，气候变暖的主要影响将是改变热状态，可能对浮游生物群落产生影响，也可能对湖泊生态系统过程产生影响。鉴于预期的巨大环境变化，改进对生态结构和功能响应的预测对于维持和管理加拿大景观中湖泊提供的生态系统服务至关重要。生态学中最近的一种方法是利用功能特征及其多样性来提高预测群落与生态系统过程之间联系的能力。虽然近年来对群落结构的功能组成部分的理论和度量进行了大量的工作，但与生态系统过程的定量联系，特别是与群落所处的环境的定量联系，在实地自然发生的条件下，一直不太清楚。加拿大的领土包括世界上大多数的湖泊和淡水，这为加拿大的研究界提供了独特的机会和责任，以发展预测其功能的生态学。这将更好地使研究人员和政策制定者在考虑到未来气候变化以及其他人为对这些重要生态系统的影响的情况下，为湖泊管理提供建议。

A major goal of modern ecological research is to improve our ability to predict the response of inherently complex systems to future changes. In an era of rapid change, including climate warming, the urgency to develop such a predictive ability is even more critical so that we can manage natural ecosystems using current and forward-looking knowledge. In lakes, the major effect of climate warming will be to alter thermal regimes, with likely consequences for plankton communities and potentially for lake ecosystem processes as well. In light of the massive environmental changes expected, improving prediction of the responses in ecological structures and functions is essential to the maintenance and management of ecosystem services provided by lakes in the Canadian landscape. A recent approach in ecology for improving the capacity to predict and link communities with ecosystem processes is to use functional traits and their diversity. While there has been intensive work in recent years on the theory and metrics of functional components of community structure, quantitative links with ecosystem processes and critically, the environment in which communities are embedded, has been less clearly made especially under naturally occurring conditions in the field. The Canadian territory includes the majority of the world’s lakes and freshwater, providing a unique opportunity and responsibility for Canada’s research community to develop a predictive ecology of their functioning. This will better enable researchers and policy makers to advise for lake management given future climate changes, as well as other human-mediated effects on these vital ecosystems. The research I have proposed will provide quantitative links between lake structure and function, taking into account variation in lake thermal regimes, which alter species interactions. I will focus on lake plankton communities, which are ideal for experimental, observation and trait work because of their small size, fast generation times, high diversity and a long history of lab-based physiological experiments. Moreover, many ecosystem processes, such as primary productivity and transfer of energy and material up the food web in lakes for fish and other vertebrates are highly influenced by the activity of planktonic organisms. The proposed work will link plankton community structure (trait and taxonomic composition, diversity) with ecosystem processes (specific and gross primary and secondary productivity, grazing pressure) by focusing on the role of the environmental effects associated to the physical thermal regimes of lakes and its temporal dynamics. Lake thermal regimes will be among the first affected by climate warming, leading to altered sequences of quiescent versus turbulent periods within and between seasons. We will use a combination of temporal and spatial observation, including cross-lake analyses, and experimental mesocosms to approach the research questions as these provide both mechanistic insight as well as tests of concepts at larger, whole-lake scales. The research will result in the training of 3 new PhD and 2 new M.Sc. students in aquatic ecology and limnology with expertise in state-of-the art field, laboratory, analytical and statistical methods. As with past personnel, those trained through the completion of this research will go on to contribute nationally and internationally to the study and management of freshwater resources that are increasingly precious as global water quality and quantity become increasingly threatened through anthropogenic and climatic disturbances.