Plankton trait flexibility and lake food web functioning

由于与人类世有关的多种强迫因素影响着生态群落的结构和功能，生态群落日益暴露于高度的时间和空间变化。有许多因素可能会通过生态和进化过程的反馈，潜在地推动群落形成新的配置。在湖泊中，与气候有关的无机或有机营养物质可获得性变化、水色或温度变化等人为强迫因素可影响种群的现有功能特征变化，从而影响浮游食物网的结构和功能。因此，拟议研究计划的长期目标是研究浮游生物群落可能如何通过其组成种群中表达的功能特征的变化来应对这些强迫因素。因此，我的实验室将继续成为浮游生物群落功能特征方法的领导者，扩展迄今的方法，主要涉及将某些生理或行为特征的不变能力分配给主要使用经典分类学方法确定的群落列表中的物种。*我提出了原创性的新研究，它将纳入浮游植物资源获取特征的动力学视角，这些特征实际上是高度灵活的，取决于当地条件。具体地说，混合营养是某些浮游植物类群中存在的摄食表型可塑性的特征，使它们能够通过吞噬或光自养获得能量和资源。我们将确定与季节变化和气候变化相关的摄食特征可塑性(混合营养)在多大程度上影响浮游生物的共存和多样性，并评估群落混合营养的相对表达如何影响食物网的结构和功能。我们将在不同季节进行相互移植和中游实验，以测试与水柱稳定性和冰盖变化的关系，以及在不同食物网背景下的关系。我的研究计划中的这一进展将涉及整合群落生态学、微生物学、分子生态学和湖沼学的新技术和实验方法，包括：流式细胞术、下一代测序、稳定同位素探测和潜水荧光测量。*通过对几个HQP的培训，这项研究将有助于基本理解浮游生物之间的生态相互作用，以及资源获取特征可塑性在促进生物多样性方面的作用。拟议的研究计划具有很高的创新性，有可能改变我们对微生物环对较高浮游食物网结构和典型北温带湖泊内通量的贡献的看法，确保更新颖和更准确地表示在人类影响下湖泊食物网的功能。

Ecological communities are increasingly exposed to high degrees of temporal and spatial variation as multiple forcing factors related to the Anthropocene influence their structure and function. There are a number of factors that may potentially drive communities to new configurations via feedbacks through ecological and evolutionary processes. In lakes, anthropogenic forcing factors, such as climate-related variation in inorganic or organic nutrient availability, water colour or thermal shifts can influence standing functional trait variation in populations to affect the structure and function of planktonic food webs. The long-term goal of the proposed research program is thus to examine how plankton communities are likely respond to such forcing factors via the variation in functional traits expressed within their component populations. My lab will thus continue to be a leader in functional trait approaches to plankton commmunities, expanding on approaches that have to date, largely involved assigning an unvarying capacity for certain physiological or behavioural traits to species in community lists identified using primarily classical taxonomic methods. ******I propose original new research, which will incorporate a dynamical perspective of phytoplankton resource acquisition traits, which are actually highly flexible, dependent on local conditions. In particular, mixotrophy characterizes the feeding phenotypic plasticity present in certain phytoplankton taxa enabling them to obtain energy and resources through phagotrophy or photoautotrophy. We will determine the degree to which feeding trait plasticity (mixotrophy) is implicated in generating plankton coexistence and diversity in relation to seasonal variation and climate change, and assess how the relative expression of community mixotrophy affects food web structure and function. We will conduct reciprocal transplant and mesocosm experiments across different seasons to test for relations with water column stability and ice cover variation, as well as under different food web contexts. This evolution in my research program will involve the incorporation of novel technologies and experimental approaches from community ecology, microbiology, molecular ecology and limnology in an integrated way, including: flow cytometry, next-generation sequencing, stable isotope probing, and submersible fluorometry. ***Through the training of several HQP, the research will contribute to basic ecological understanding of the ecological interactions between plankton and the role of resource acquisition trait plasticity in contributing to biodiversity. The proposed research program is highly innovative and has the potential to shift how we view the contribution of the microbial loop to the higher planktonic food web structure and to fluxes within typical north temperate lakes, ensuring more novel and more accurate representation of lake food web functioning under anthropogenic influence.