Ecological Dynamics of the Plant-Arbuscular Mycorrhizal Fungal Mutualism: Contribution to Plant Species Turnover and Coexistence

美国心脏地带的标志性高草草原在经历了火灾和放牧之后，经历了一个不断更新的过程。更新包括提供长期共存和维持多样性的物种周转。最近，有研究表明，一种穿透草原植物根部的真菌在它们争夺资源的过程中发挥着重要作用，而且这种相互作用在物种之间存在差异。因此，真菌会影响周转顺序的发生。这种相互作用的细节，以及它是否帮助了一些物种，是否阻碍了其他物种，目前尚不清楚。该项目将以前所未有的详细程度确定这种互动如何影响续订过程。这项研究将有助于恢复中西部自然草原社区的努力。此外，该项目将为学生提供培训机会，并为高中教师发展计划做出贡献。越来越多的工作已经确定了土壤生物在植物物种共存和演替过程中的重要作用。对土壤有机体动力学缺乏了解，限制了对这些系统潜在动力学的洞察。这一差距将在观察、实验和建模阶段得到解决。观测将跨越时间和空间，以监测丛枝菌根真菌组成的变化和不同生活史的多种植物的植物生长。由这些真菌变化引起的植物种群的动态将被检验。将设计和进行操纵性实验，以区分和量化寄主对优势菌根的资源分配对真菌竞争能力的影响。一个概念模型，包括模拟，将产生一个新的理论框架，将植物的生理可塑性和生活史的权衡与植物-丛枝菌根群落的反馈结合在一起。

The iconic tallgrass prairie of the American heartland undergoes a constant process of renewal following fire and grazing. The renewal consists of a turnover of species that provides for long-term coexistence and the maintenance of diversity. Recently, it has been revealed that a type of fungus that penetrates that roots of prairie plants plays an important role in how they compete for resources, and these interactions differ among species. The fungi thus affect how the sequence of turnover takes place. The details of this interaction, and whether it helps some species and hinders others, is yet unknown. This project will determine how this interaction affects the renewal process in unprecedented detail. This research will aid in efforts to restore natural prairie communities in the Midwest. Additionally, the project will provide training opportunities for students and contribute to a high school teacher development program.A growing body of work has identified important roles of soil organisms in plant species coexistence and turnover during succession. Insight into the potential dynamics of these systems is limited by a poor understanding of soil organism dynamics. This gap will be addressed in observational, experimental, and modeling stages. Observations will span time and space in monitoring changes in arbuscular mycorrhizal fungal composition and plant growth across multiple plant species of varying life history. The dynamics of plant populations resulting from these fungal changes will be examined. Manipulative experiments will be designed and conducted to differentiate and quantify the impact of allocation of resources by the hosts to preferred mycorrhizae from fungal competitive ability. A conceptual model, including simulation, will be developed to produce a new theoretical framework that integrates plant physiological plasticity and life history trade-offs with plant-arbuscular mycorrhizal community feedbacks.