The role of local environment and geographical distance in determining community composition of arbuscular mycorrhizal fungi at the landscape scale

• Published in: The ISME Journal Vol. 7; no. 3; pp. 498 - 508
• Main Authors: Hazard, Christina, Gosling, Paul, van der Gast, Christopher J, Mitchell, Derek T, Doohan, Fiona M, Bending, Gary D
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01-03-2013; Nature Publishing Group
• Subjects: 631/158/670; 631/158/852; 631/326/193/2539; 631/449/2676/2061; arbuscular mycorrhizas; Bioassays; Biodiversity; Biomedical and Life Sciences; Community composition; Ecology; Ecosystem; Environmental factors; Evolutionary Biology; Fungi; Habitat; Habitats; Ireland; Land use; Landscape; Life Sciences; Lolium - microbiology; Lolium perenne; Microbial Ecology; Microbial Genetics and Genomics; Microbiology; Mycorrhizae - classification; Mycorrhizae - genetics; Mycorrhizae - physiology; Original; original-article; Pasture; pH effects; Plant communities; Plant Roots - microbiology; Plant species; Polymorphism, Restriction Fragment Length; Rainfall; RNA, Ribosomal, 18S - genetics; Roots; rRNA 18S; Sampling; Soil - chemistry; Soil Microbiology; Soil types; Terrestrial ecosystems; Trifolium - microbiology; Trifolium repens; host preference; soil type; diversity; land use; arbuscular mycorrhizal fungi; biogeography
• ISSN: 1751-7362; 1751-7370
• DOI: 10.1038/ismej.2012.127

Arbuscular fungi have a major role in directing the functioning of terrestrial ecosystems yet little is known about their biogeographical distribution. The Baas-Becking hypothesis (‘everything is everywhere, but, the environment selects’) was tested by investigating the distribution of arbuscular mycorrhizal fungi (AMF) at the landscape scale and the influence of environmental factors and geographical distance in determining community composition. AMF communities in
Trifolium repens
and
Lolium perenne
roots were assessed in 40 geographically dispersed sites in Ireland representing different land uses and soil types. Field sampling and laboratory bioassays were used, with AMF communities characterised using 18S rRNA terminal-restriction fragment length polymorphism. Landscape-scale distribution of AMF was driven by the local environment. AMF community composition was influenced by abiotic variables (pH, rainfall and soil type), but not land use or geographical distance.
Trifolium repens
and
L. perenne
supported contrasting communities of AMF, and the communities colonising each plant species were consistent across pasture habitats and over distance. Furthermore,
L. perenne
AMF communities grouped by soil type within pasture habitats. This is the largest and most comprehensive study that has investigated the landscape-scale distribution of AMF. Our findings support the Baas-Becking hypothesis at the landscape scale and demonstrate the strong influence the local environment has on determining AMF community composition.