| This dissertation focuses on soil microbial ecology. Throughout, I have strived to understand which environmental factors influence microbial communities and in turn how they influence plant communities. My specific objectives were to: (1) Describe how fungal growth and ecology is shaped by soil structure, (2) Determine which environmental gradients shape the species composition of arbuscular mycorrhizal fungal communities, (3) Determine the impact of serpentine soil, an extreme soil environment present worldwide, on arbuscular mycorrhizal fungal communities, and (4) Investigate the influence of microbial communities on plant diversity in tallgrass prairie. These questions are approached from a variety of angles including a literature review and both observational and experimental studies. My results indicate broadly that soil characteristics play a strong role in determining microbial community composition although serpentine soil is not as influential as expected. Results also suggest that soil microorganisms play an important role in structuring plant community diversity and composition. My work has implications for the restoration of plant communities, maintenance of ecosystem services, and basic ecological theory of species coexistence. |
