Reducing tillage could result in less production of a potent greenhouse gas, according to a study out of Penn State University.

The greenhouse gas in question is nitrous oxide (N₂O), which has a global warming potential about 300 times greater than that of carbon dioxide (CO₂), according to the U.S. Environmental Protection Agency. N₂O emissions are perhaps best known as the greenhouse gas ingredient in cow stomach emissions (flatulent and otherwise), although N₂O is also emitted naturally as part of the nitrification process, and is a by-product of the application of nitrogen-heavy fertilizers.

The study, "Tillage intensity and plant rhizosphere selection shape bacterial-archaeal assemblage diversity and nitrogen cycling genes" was published in the journal "Soil and Tillage Research."

The study took samples from three different types of long-term tillage systems: no-till, chisel-disk plowing, and moldboard plowing, which researchers defined as low, medium and high disturbance. They also collected samples from both corn and soybeans, as well as samples collected at different growth stages in each plant.

Researchers collected the samples from a 40-year ongoing tillage experiment in Pennsylvania.

In addition to growth stage and management system, samples were also broadly divided into "bulk" soil samples, or samples taken directly from fields, and "rhizosphere" soil samples, or soil collected from among the roots of the plants themselves.

They next subjected the samples to a kind of test known as a PCR amplification, which is designed to take certain segments of DNA and replicate them again and again to indicate whether they are present in a sample, and in what percentage.

Researchers ultimately found DNA evidence that members of families of bacteria capable of turning N into ammonium  were more common in bulk no-tilled soil than in soils for minimum or high tillage. What is more, no-till soils contained fewer genes for bacteria known to create N₂O from nitrogen.

"Soils managed with low intensity-tillage appeared to have lower abundances of genes representing denitrifiers and N₂O-reducers but greater abundances of bacteria responsible for other N conversions," they write, in the study's conclusion. "Results of this study suggest that minimizing disturbances to agricultural soils may provide an opportunity for reducing N₂O emissions."