Climate Change Impacts on the Structure and Function of Lake Plankton Communities

湖泊生态系统面临的一些最严重的人为挑战是全球气候变暖、湖泊流域的土地利用变化以及包括外来物种在内的浮游生物的扩散加剧。这些挑战提供了“自然实验”，允许生态学家探索群落是如何构建的以及生态系统功能如何与这种结构相关的基本问题。我特别关注气候变化的影响，我建议更具体地研究哪些生态系统特征对浮游生物群落结构最关键，进而研究群落结构变化如何影响湖泊生态系统功能。我的方法是在湖内尺度上研究这样的问题，以及利用跨湖比较和影响湖泊的景观水平特征。此外，我对通过从分类学和功能角度明确考虑组成和多样性的各个方面来评估社区结构的各种度量感兴趣。此外，我将探索多样性的丰富性和均衡性两个组成部分。迄今为止，在研究群落结构(生物多样性)和生态系统功能之间联系的研究中的一个主要弱点是，在自然情况下或在动物生物体中几乎没有做过任何工作。因此，我提议的研究将通过评估食物网和生态系统循环的重要指标以及湖泊浮游植物和浮游动物的速率来填补一个关键的知识空白。研究将涉及时间序列和景观水平的观察，短期容器实验，以及更大规模的实验。先进的统计模型将使我们能够梳理出驱动特定社区和生态系统变化的机制。

Some of the most critical anthropogenic challenges to lake ecosystems are global climate warming, land-use changes to lake watersheds and enhanced dispersal of planktonic organisms, including exotic species. Such challenges provide "natural experiments" which allow ecologists to explore the basic questions of how communities are structured and how ecosystem function is related to this structure. Focusing in particular on climate change effects, I am proposing to examine more specifically, which ecosystem features are most critical for plankton community structure and in turn, how altered community structure influences lake ecosystem function. My approach invoves examining such questions at the within-lake scale as well as by taking advantage of cross-lake comparisons and landscape-level features affecting lakes. Also, I am interested in a variety of metrics for assessing community structure by explicitly considering aspects of composition and diversity from both taxonomic and functional perspectives. Moreover, I will explore both the richness and evenness components of diversity. A major weakness in research that has examined the link between community structure (biodiversity) and ecosystem function to date is that little to no work has been done in natural situations, nor with animal organisms. My proposed research will therefore fill a critical knowledge gap by assessing important indicators of food web and ecosystem cycling and rates in lake phytoplankton and zooplankton. Research will involve time series and landscape-level observations, short-term container experiments, as well as larger scale experiments. Advanced statistical modelling will enable us to tease apart the mechanisms driving particular commmunity and ecosystem changes.