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

湖泊生态系统面临的一些最关键的人为挑战是全球气候变暖、湖泊流域土地利用变化以及包括外来物种在内的浮游生物扩散加剧。这些挑战提供了“自然实验”，使生态学家能够探索群落如何构成以及生态系统功能如何与这种结构相关的基本问题。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，反过来，群落结构的改变如何影响湖泊生态系统功能。我的方法包括在湖内尺度上检查这些问题，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方面来评估群落结构的各种指标很感兴趣。此外，我将探讨多样性的丰富性和均匀性组成部分。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的联系方面，一个主要的弱点是，对自然环境和动物有机体的研究几乎没有。因此，我提出的研究将通过评估湖泊浮游植物和浮游动物的食物网和生态系统循环和速率的重要指标来填补一个关键的知识空白。研究将包括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群落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.