JIJITANG2014-06-30 4:22 PM

Farmers could cut emissions if they fertilized ‘just right’

When the amount of fertilizer exceeds crop needs, emissions of nitrous oxide—a greenhouse gas produced in the soil following nitrogen addition—rises faster than expected.

Nitrous oxide is the third most important greenhouse gas, behind only carbon dioxide and methane, and destroys stratospheric ozone. Agriculture accounts for around 80 percent of human-caused nitrous oxide emissions worldwide, which have increased substantially in recent years, primarily due to increased nitrogen fertilizer use.

New research suggests farmers could cut emissions if they matched the amount of fertilizer applied to how much the plants actually needed—not too little and not too much.

Precise application
“Our specific motivation is to learn where to best target agricultural efforts to slow global warming,” says Phil Robertson, director of the Kellogg Biological Station Long-term Ecological Research Program at Michigan State University and senior author of the paper published in the Proceedings of the National Academy of Sciences.

“Agriculture accounts for 8 to 14 percent of all greenhouse gas production globally. We’re showing how farmers can help to reduce this number by applying nitrogen fertilizer more precisely.”

The production of nitrous oxide can be greatly reduced if the amount of fertilizer crops need is exactly the amount that is applied to farmers’ fields. Simply put, when plant nitrogen needs are matched with the nitrogen that’s supplied, fertilizer has substantially less effect on greenhouse gas emission, Robertson says.

The research also informs fertilizer practices in underfertilized areas such as sub-Saharan Africa, says researcher Iurii Shcherbak, lead author of the paper.

“Because nitrous oxide emissions won’t be accelerated by fertilizers until crop nitrogen needs are met, more nitrogen fertilizer can be added to underfertilized crops with little impact on emissions,” she says.

Adding less nitrogen to overfertilized crops elsewhere, however, would deliver major reductions to greenhouse gas emissions in those regions.

The study provides support for expanding the use of carbon credits to pay farmers for better fertilizer management. Carbon credits for fertilizer management are now available to US corn farmers. This paper provides a framework for using this system around the world.

The National Science Foundation, the Department of Energy’s Great Lakes Bioenergy Research Center, and the Electric Power Research Institute funded the study. MSU AgBioresearch also contributed to Robertson’s work.

Original Article
<Global metaanalysis of the nonlinear response of soil nitrous oxide (N2O) emissions to fertilizer nitrogen >, Published on Journal <PNAS> in June 2014






0 Following 3 Fans 0 Projects 310 Articles


Changes to the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) have resulted in families eating more fruits and vegetable

Read More

In contests drawn from game theory, chimpanzee pairs consistently outperform humans in games that test memory and strategic thinking.A new study, condu

Read More

Publishing is one of the most ballyhooed metrics of scientific careers, and every researcher hates to have a gap in that part of his or her CV. Here’s

Read More

Pornography triggers brain activity in people with compulsive sexual behaviour -- known commonly as sex addiction -- similar to that triggered by drugs

Read More

In a recent survey, academic staff at the University identified the interrelated skills of writing and reasoning as the two most important skills for s

Read More

In a recent survey, academic staff at the University identified the interrelated skills of writing and reasoning as the two most important skills for s

Read More

Reading cautionary tales like The Boy Who Cried Wolf and Pinocchio to little kids might not be the best way to teach them to tell the truth.New researc

Read More

Those flat, glassy solar panels on your neighbor’s roof may be getting a more efficient makeover, thanks to a new class of solar-sensitive nanoparticle

Read More

Physicists have overcome a major challenge in the science of measurement using quantum mechanics. They’ve used multiple detectors to measure photons in

Read More

If you want to slow down long enough to smell the proverbial roses, you might want to move to a neighborhood with fewer drive-thru restaurants, researc

Read More