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Vanessa Bailey, PhD

Soil scientist

Vanessa Bailey, PhD

Soil scientist


Events such as floods and droughts have dramatic, visible effects on landscapes. But even after the waters recede or the rains finally come, the land is changed in ways that have implications for climate change. Vanessa Bailey studies these and other processes related to soil and the carbon contained within.

"Soil is the largest terrestrial reservoir of carbon," Bailey said. "We don't completely understand how and why carbon in soil stays where it is, and it’s difficult to predict losses and transformations of soil carbon."

She studies how historical precipitation and drought change the microbial processes and soil properties that produce greenhouse gases from soil. She is also investigating how nutrients such as nitrogen, phosphorus, and iron affect soil carbon stability in complex coastal landscapes that are subject to tides and floods.

Bailey and colleagues have conducted research showing, for example, that the rate at which microbes are transferring carbon from soil to the atmosphere has increased over a 25-year time period. She also manages one of the Department of Energy's largest coastal research projects, COMPASS, where she is leading efforts to understand the interface between land and sea.

Flooding and drought occur across geographically vast areas, but significant changes occur at a microscopic level—among microbes in the soil. Not only is the rate of microbial activity increasing, Bailey said, but these extreme events change the quality of the microbial habitats in soils.

“We need to understand how moisture extremes affect forms of soil carbon, and also how water moves through soil under different conditions,” she said. “This can help us predict the timing and extent to which these microbes release greenhouse gases.”

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In the News

Below Our Feet, a World of Hidden Life.” Quantamagazine, June 16, 2015.