Plant diversity predicts beta but not alpha diversity of soil microbes across grasslands worldwide

Prober, Suzanne M. and Leff, Jonathan W. and Bates, Scott T. and Borer, Elizabeth T. and Firn, Jennifer and Harpole, W. Stanley and Lind, Eric M. and Seabloom, Eric W. and Adler, Peter B. and Bakker, Jonathan D. and Cleland, Elsa E. and DeCrappeo, Nicole M. and DeLorenze, Elizabeth and Hagenah, Nicole and Hautier, Yann and Hofmockel, Kirsten S. and Kirkman, Kevin P. and Knops, Johannes M. H. and La Pierre, Kimberly J. and MacDougall, Andrew S. and McCulley, Rebecca L. and Mitchell, Charles E. and Risch, Anita C. and Schuetz, Martin and Stevens, Carly J. and Williams, Ryan J. and Fierer, Noah (2015) Plant diversity predicts beta but not alpha diversity of soil microbes across grasslands worldwide. Ecology Letters, 18 (1). pp. 85-95. ISSN 1461-023X

Abstract

Aboveground-belowground interactions exert critical controls on the composition and function of terrestrial ecosystems, yet the fundamental relationships between plant diversity and soil microbial diversity remain elusive. Theory predicts predominantly positive associations but tests within single sites have shown variable relationships, and associations between plant and microbial diversity across broad spatial scales remain largely unexplored. We compared the diversity of plant, bacterial, archaeal and fungal communities in one hundred and forty-five 1m(2) plots across 25 temperate grassland sites from four continents. Across sites, the plant alpha diversity patterns were poorly related to those observed for any soil microbial group. However, plant beta diversity (compositional dissimilarity between sites) was significantly correlated with the beta diversity of bacterial and fungal communities, even after controlling for environmental factors. Thus, across a global range of temperate grasslands, plant diversity can predict patterns in the composition of soil microbial communities, but not patterns in alpha diversity.