The University of Arizona

How Microbes Eat Rocks

By Daniel Stolte, September 29, 2010

Biosphere 2 researchers received a $424,623 grant from the National Science Foundation to study how plants and microbes interact to chew away on minerals and make new soil.

This microscopic image reveals an example of a mycorrhiza in a mesquite tree. Mycorrhiza is a mutually beneficial association between plant roots and a fungus, seen here as ball, and thread-like structures in which each partner makes nutrients available that the other can't produce on its own. (Photo credit: F. Solis-Dominguez)
This microscopic image reveals an example of a mycorrhiza in a mesquite tree. Mycorrhiza is a mutually beneficial association between plant roots and a fungus, seen here as ball, and thread-like structures in which each partner makes nutrients available that the other can't produce on its own. (Photo credit: F. Solis-Dominguez)

The National Science Foundation has awarded a three-year, $424,623 grant to UA researchers to investigate how plants and microbes influence mineral weathering and leaching of mineral-forming chemical elements to make new soil.

"We will investigate how Ponderosa Pine and Buffalo Grass – two plant species common to the western U.S. – and microorganisms work together to mine nutrients from rock and make new soil," said project leader Katerina Dontsova, an assistant research professor at Biosphere 2 Earthscience.

Biosphere 2 Director Travis Huxman, a professor in the UA's department of ecology and evolutionary biology, said: "Biosphere 2 is ideally suited to serve as a center for this work because of its focus on interdisciplinary research that addresses Earth system processes." 

The researchers will be able to manipulate parameters such as rock type and presence or absence of microorganisms and/or plants independently and study the effects on weathering processes, nutrient uptake by plants and leaching of minerals into the soil.

In addition to Dontsova and Huxman, the team includes Raina Maier, associate director of the UA's Superfund Research Program, Jon Chorover, a professor in the UA's department of soil, water and environmental science, and Julia Perdrial, a researcher in the same department.

The team will be able to apply some of the techniques developed during the Superfund Research Program.

"We look at the effects of plant growth on geochemistry in mine tailings as an example of how biological weathering transforms the Earth's surface," Maier said.

The new project is expected to maintain a two-way information and methodological transfer that would benefit both the NSF-funded project and existing mine-tailing research. 

"Plants and microbes employ similar mechanisms in both natural and disturbed environments, such as mine-tailings, to make soils a better environment for life," Dontsova said.

Funded through NSF's Emerging topics in Biogeochemistry program, which focuses on research that transcends Earth and biological science, the project will closely integrate with related interdisciplinary projects at the UA, including the Jemez River Basin – Santa Catalina Mountains Critical Zone Observatory (led by Chorover), the UA Superfund Research Program, the Biosphere 2 Landscape Evolution Observatory, and a grass mortality study, soon to be featured by National Geographic TV. 

Contacts

Hassan Hijazi

Biosphere 2

520-955-3657

hhijazi@email.arizona.edu