Scaling up from local plant - plant and plant-soil relationships to landscape level patterns of diversity and process

我的研究计划调查植物-植物和植物-土壤的相互作用如何结构植物和土壤群落的多样性和组成。我的目标是：1）调查当地规模的植物-微生物关系如何与大规模的非生物和气候因素相互作用，以构建植物和土壤微生物群落的群落水平模式; 2）解开细尺度植物生根模式的机制，特别是土壤养分异质性和植物根系竞争的作用。 植物与植物和植物与土壤的相互作用基本上是局部的，发生在毫米到厘米的尺度上。这些精细尺度的过程已经得到了很好的研究，但是对于它们如何影响植物和土壤群落的大尺度模式却知之甚少。扩大到景观是具有挑战性的，因为许多相互作用的生态机制需要评估。我建议联系当地规模的直接植物-土壤关系的社区模式和过程的规模范围从当地的植物群落，中等规模的因素，如草食动物和地形，和植被规模的因素，如气候和土壤母质。空间结构方程模型将使我能够评估机制的相对强度和重要性如何在尺度上变化。这将使我能够解开中到大规模的因素，如环境条件和景观历史与精细尺度的生物相互作用，以结构社区。通过表征植物根系和土壤微生物群之间在广泛的气候和土壤梯度的局部规模的多营养关系，我将研究如何充分理解植物根系微生物的联系结构的植物和土壤群落的多样性和组成的大规模模式。最后，我将通过实验研究这些关系如何反馈到个体植物，研究个体植物的生根模式如何受到细尺度土壤条件的影响。 我将利用一个多尺度的实地调查计划，以表征植物和土壤真细菌，古细菌和真菌群落在1000平方公里的原生草原地区。采样将遵循空间明确的设计，以捕捉从单个植物-土壤相互作用（<25厘米）到土壤母质和气候效应（1- 100公里）的过程。博士学位。学生将研究植物尺度因子如何与精细尺度植物-土壤关系相互作用，以构建植物和土壤群落组成。理学硕士。学生将着重于地方和植物水平因素如何影响植物根系多样性和根系位置的模式。最后，选择潜在的机制驱动精细规模的植物生根模式，包括土壤肥力，土壤养分异质性的作用，和竞争的植物根系将由第二个硕士研究。学生.

My research program investigates how plant-plant and plant-soil interactions structure plant and soil community diversity and composition. My objectives for this grant are to 1) investigate how local-scale plant-microbial relationships interact with large scale abiotic and climate factors to structure landscape-level patterns in plant and soil microbial communities, and 2) to disentangle the mechanisms underlying fine-scale plant rooting patterns, particularly the roles of soil nutrient heterogeneity and plant root competition. Plant-plant and plant-soil interactions are fundamentally local, occurring at scales of millimetres to centimetres. These fine-scale processes are well studied, yet comparatively little is known about how they influence broad-scale patterns in plant and soil communities. Scaling up to landscapes is challenging because many interacting ecological mechanisms need to be assessed. I propose to link the local scale of direct plant-soil relationships to community patterns and processes at scales ranging from the local plant community, mid-scale factors such as herbivory and topography, and landscape-scale factors such as climate and soil parent material. Spatial structural equation modeling will allow me to evaluate how the relative strength and importance of mechanisms changes across scale. This will allow me to disentangle how medium to larger scale factors such as environmental conditions and landscape history interact with fine scale biological interactions to structure communities. Through characterizing the local-scale multitrophic relationships between plant roots and soil microbiota across broad climatic and soil gradients, I will examine how the well understood plant root-microbe linkages structure broad-scale patterns of plant and soil community diversity and composition. Finally, I will experimentally examine how these relationships feed back to individual plants by examining how the rooting patterns of individual plants are affected by fine-scale soil conditions. I will utilize a multi-scale field survey program to characterize the plant and soil eubacteria, archaea, and fungal communities across a 1000 km2 region of native prairie. Sampling will follow a spatially explicit design to capture process ranging from individual plant-soil interactions (<25cm) to soil parent material and climate effects (1-100km). A PhD. student will investigate how landscape-scale factors interact with fine scale plant-soil relationships to structure plant and soil community composition. An MSc. student will focus on how local and landscape-level factors influence patterns of plant root diversity and root placement. Finally, a selection of potential mechanisms driving fine-scale plant rooting patterns including the role of soil fertility, soil nutrient heterogeneity, and competing plant roots will be investigated by a second MSc. student.