The plants eye view: disentangling plant-plant, plant-herbivore, and plant-soil interactions

我的研究项目是调查植物和土壤群落多样性之间的因果关系。我最近的工作集中在植物与植物之间的相互作用，特别是入侵物种取代本地物种的负面相互作用，如何结构植物和土壤群落。在这个授权周期中，我将扩大我的项目范围，以研究草食对植物-土壤相互作用的影响。草食-植物-土壤之间的联系一直以来都很难解开，因为植物-土壤反馈的强度和方向被植物物种和非生物条件之间的多种相互作用所改变。虽然我们知道这些机制可以分别成为构建植物和土壤群落多样性和功能的重要力量，但这些机制的相对重要性很少在单个自然群落中进行研究。我在这个拨款周期的具体目标是：

My research program investigates the causal linkages between plant and soil community diversity. My most recent work focuses on how plant-plant interactions, particularly the negative interactions where an invasive species replaces a native species, structure plant and soil communities. In this granting cycle, I will expand my program scope to examine herbivory impacts on plant-soil interactions. Herbivore-plant-soil linkages have historically been notoriously difficult to disentangle because the strength and direction of plant-soil feedbacks are modified by multi-way interactions among the plant species and abiotic conditions. While we know that these mechanisms can separately be important forces structuring plant and soil community diversity and function, the relative importance of these mechanisms have rarely been investigated in a single natural community. My specific objectives for this granting cycle are to: 1. measure the long-term impacts of cattle grazing on fescue grassland plant and soil community structure, 2. evaluate the relative importance of grazing induced changes in root biomass allocation and root exudate profiles, 3. examine how the known long-term impacts of plant invasion arise from short-term herbivore-plant-soil processes operating at the moment of invasion. My research program is important because, while large mammal herbivory is known to structure plant-soil relationships, few studies have by attempted to disentangle the roles of direct plant-plant interactions and abiotic conditions from herbivory impacts. My research program will be among the first to investigate how herbivory interacts with plant-plant and environmental drivers to structure plant-soil interactions. Moving from the general to specific plant-soil processes, my program will be among the first to directly observe the fine-scale belowground dynamics at the moment of a plant invasion. The focal species for this work, Smooth Brome, is one of the most problematic invasive species in prairie grasslands. The broader ecosystem processes and consequences driving Brome invasion are well understood, yet little is known about the interactions between individual Brome plants and the established native plants that Brome displaces. My work will thus be among the first to study a plant invasion from the plants eye view, examining how aboveground and belowground processes interact through the invasion process in real time.