NAU Scientist: Dry Climates Diminish Microbial Diversity

Dec 14, 2015

Deserts like the American Southwest are expected to get drier as the climate warms. That’s bad news for soil microbes, according to a global study co-authored by researchers at Northern Arizona University.

Desert ecosystem near Escalante, Utah
Credit USGS


This study is the first to look at soil microbes in drylands all over the world. The researchers collected soil samples from 80 dryland ecosystems, on every continent except Antarctica. It found bacteria and fungi were less numerous and less diverse in drier climates.  

NAU soil ecologist Matthew Bowker is one of the study’s authors. “Not only are plants and animals going to respond to climate change, but it seems that also microbes that live in the soil would too,” Bowker said. “You would expect it, but here it is, loud and clear.”

Bowker says drylands cover 40 percent of the Earth’s landmass, and climate models predict they’ll expand. If microbial diversity diminishes in these regions, soil will become less fertile, and the effects will ripple up the food chain.

Bowker’s next project will be to study livestock grazing in drylands with the international team.