Root Foraging, Competition, and Coexistence in Heterogeneous Soils

竞争在植物群落结构中起着关键作用，因此，了解植物竞争相互作用的机制对于成功管理自然和人工系统至关重要。然而，尽管经过多年的研究，植物竞争相互作用的性质及其与环境条件的关系仍未完全理解，并且仍在争论中。地下竞争及其与土壤资源精细尺度异质性的关系是一个特别少探索的领域，尽管土壤异质性在自然界中无处不在。本研究将采用实验和模型相结合的方法研究空间异质性土壤中根系觅食性状及其与植物竞争能力和植物群落多样性的关系。温室和田间试验将用于测量根系觅食的规模、精度和速率，以及它们与多年生草本物种（包括一种重要的入侵杂草）竞争能力的关系。地下面积不对称现象及其在植物竞争能力和群落结构中的作用是本研究的一个特别新颖的焦点。野外实验和模拟模型将探讨精细尺度异质性是否影响竞争大小对称和竞争等级，以及对植物物种共存和植物群落多样性维持的影响。这项研究有可能改变我们对根系竞争及其在植物群落结构中的作用的理解。

Rajaniemi0129493Competition can play a key role in structuring plant communities, and understanding the mechanisms of plant competitive interactions is therefore critical for successful management of natural and cultivated systems. Yet despite years of study, the nature of plant competitive interaction and their relationship to environmental conditions is incompletely understood and continues to be debated. Belowground competition and its relation to fine-scale heterogeneity in soil resources is a particularly little explored area, despite the ubiquity of soil heterogeneity in nature. This research will use experimental and modeling approaches to investigate root foraging traits and their relationship to plant competitive ability and plant community diversity in spatially heterogeneous soil. Greenhouse and field experiments will be used to measure the scale, precision, and rate of root foraging and their relationship to the competitive ability of herbaceous perennial species, including an important invasive weed. An especially novel focus of this research is the phenomenon of belowground size asymmetry and its role in plant competitive ability and community structure. Field experiments and simulation modeling will examine whether fine-scale heterogeneity affects competitive size symmetry and competitive hierarchies, and the consequences for plant species coexistence and the maintenance of plant community diversity. This research has the potential to redirect our understanding of root competition and its role in the structure of plant communities.