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了生态群落的结构和功能，它们越来越暴露于高度的时空变化之中。有许多因素可能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可用性变化、水体颜色或热变化等人为强迫因素可影响种群的长期功能性状变化，从而影响浮游食物网的结构和功能。因此，该研究计划的长期目标是研究浮游生物群落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，我的实验室将继续在浮游生物群落的功能性状方法方面处于领先地位，扩展迄今为止的方法，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。我建议进行新的研究，这将包括浮游植物资源获取特征的动态视角，这实际上是高度灵活的，依赖于当地条件。特别是，混合营养表现出某些浮游植物类群存在的摄食表型可塑性，使它们能够通过吞噬或光自养获得能量和资源。我们将确定在季节变化和气候变化的影响下，摄食性状可塑性（混合营养）对浮游生物共存和多样性产生的影响程度，并评估群落混合营养的相对表达如何影响食物网结构和功能。我们将在不同的季节进行相互移植和中生态实验，以测试水柱稳定性和冰盖变化之间的关系，以及在不同的食物网背景下。在我的研究计划中，这一演变将涉及到从群落生态学、微生物学、分子生态学和湖沼学中整合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定。通过对几个HQP的训练，本研究将有助于对浮游生物之间的生态相互作用和资源获取性状可塑性在生物多样性中的作用有基本的生态学认识。拟议的研究计划具有高度创新性，有可能改变我们对微生物环对更高浮游食物网结构和典型北温带湖泊通量的贡献的看法，确保在人为影响下更新颖、更准确地表示湖泊食物网的功能。

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.