Monday, 15 April 2013

To cut emissions, match fertilizer to soil

An article on Futurity (research news from universities in the US, UK, Canada, and Australia) describes a study published in the Proceedings of the National Academy of Sciences, aimed at understanding the sources of nitrous oxide and nitric oxide by different microbial processes, especially following the application of certain fertilizer nitrogen types.

“Agriculture is the main source of nitrous oxide globally, so this study is a starting point to help us understand how to manage and control it,” says University of California, Davis, professor of soil biogeochemistry William Horwath, whose lab conducted the study.

In the paper, the authors say their results imply that management practices such as fertilizer choice affect how much nitrous oxide is released. Specifically, to reduce nitrous oxide emissions, fertilizer applications of urea should be avoided in soils where oxygen is limited, they write.

On the other hand, practices that increase soil aeration, reduce compaction, and enhance soil structure using organic matter could decrease nitrous oxide emissions from agricultural soils. Using nitrification inhibitors could help, as well.
“The results of this study will change the way we think about the source of nitrous oxide from soil,” Horwath says. “It will help researchers and people making fertilizer recommendations begin to understand that they need to consider different soil processes more explicitly.”

Read the article here.