Soil Arbuscular Mycorrhizal Fungi Metagenome

Biological invasions are a major factor contributing to global change and ecosystem degradation. Many of the harmful effects of biological invasions are caused by alterations in the richness and abundance of native versus invasive organisms. However, the effects of invasive species on the diversity of native biota are often scale-dependent and may show opposing trends at different spatial extents. For obligately symbiotic organisms such as arbuscular-mycorrhizal fungi (AMF), the effects of plant invasions on their diversity remain largely unknown. To examine possible scale-dependent changes in AMF with plant invasions, we sampled AMF across spatial gradients and used hierarchical modeling to relate species richness to area. Our results show that AMF have a species-area relationship similar to many macroorganisms and that biological invasions decrease species richness at small spatial scales. These results provide some of the first evidence of the scale-dependent and effects of invasions on microbial mutualist diversity.