UC Merced

“Carbon Stability in Agricultural Soils: Finding the Right Balance”

ABSTRACT

Soils represent our greatest terrestrial carbon reservoir, yet they risk becoming major sources of atmospheric carbon under certain conditions. Traditional agricultural practices have accelerated carbon loss since the advent of modern farming, contributing significantly to atmospheric carbon levels.

Conservation management—combining organic inputs with reduced soil disturbance—offers potential for capturing atmospheric CO2 and storing it in soil. My research compares 20 years of standard versus conservation management in California’s Central Valley, examining resulting changes in soil physical and chemical properties.

After two decades, conservation-managed soils showed significantly increased carbon, nitrogen, and air diffusivity. However, these enhanced properties unexpectedly led to greater carbon flux at moisture levels typical in agricultural systems, suggesting we may unintentionally be releasing more carbon and potentially halting carbon accumulation.

In an era of limited water resources, this research highlights the importance of developing agricultural systems that balance multiple priorities: water conservation, food production, and climate stability. Effective soil carbon management requires understanding these complex interactions rather than applying one-size-fits-all solutions.