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

在火灾和放牧之后，美国中心地带标志性的高草草原经历了一个不断更新的过程。更新包括物种的更替，提供长期共存和维持多样性。近年来，人们发现一种渗透到草原植物根部的真菌在草原植物的资源竞争中起着重要的作用，而这种相互作用在物种之间是不同的。因此，真菌会影响细胞更替的顺序。这种相互作用的细节，以及它是否帮助了一些物种，阻碍了另一些物种，目前还不得而知。该项目将以前所未有的细节确定这种相互作用如何影响更新过程。这项研究将有助于恢复中西部的自然草原社区。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。越来越多的研究表明，土壤生物在植物演替过程中对物种的共存和更替具有重要作用。对这些系统的潜在动力学的深入了解受到对土壤生物动力学了解不足的限制。这一差距将在观测、实验和建模阶段加以解决。观察将跨越时间和空间，监测不同生活史的多种植物丛枝菌根真菌组成和植物生长的变化。由这些真菌变化引起的植物种群的动态将被检查。操纵性实验将被设计和实施，以区分和量化宿主分配资源对优选菌根和真菌竞争能力的影响。将开发一个概念模型，包括模拟，以产生一个新的理论框架，将植物生理可塑性和生活史权衡与植物丛枝菌根群落反馈相结合。

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.