12 Sep 2018

Press Release: Agricultural Contribution to California Smog Questioned


Several inconsistencies undermine the conclusion that agriculture is a dominant source of nitrogen oxides.

For Immediate Release

September 12, 2018 - Peachtree Corners, Georgia, USA – A paper published January 2018 in Science Advances reported that losses from cropland of the smog-forming gases known as NOx contribute 20 to 32 percent of the state of California’s total emissions. A team led by the International Plant Nutrition Institute (IPNI), however, has published a technical comment (released on September 12) questioning the findings.

The comment, outlining several inconsistencies, suggests that agricultural emissions are considerably lower. It argues that the findings are undermined by the lack of agreement between modeled estimates and previous field measurements, the inappropriate extrapolation of field measurements taken during high emission periods, and the overestimation of nitrogen fertilizer consumption in California. The published comment calls for increased transparency in the assessment of nitrogen loss pathways, to support responsible management of crop nutrients in agriculture.

About IPNI
IPNI is a global organization with initiatives addressing the world's growing need for food, fuel, fiber and feed. The mission of IPNI is to develop and promote scientific information about the responsible management of plant nutrition for the benefit of the human family.

Ref #18057

IPNI Contacts
Dr. Terry Roberts, President; info@ipni.net
Dr. Tom Bruulsema, VP Americas & Director of Research, Tom.Bruulsema@ipni.net
Dr. Robert Mikkelsen, VP Communications, RMikkelsen@ipni.net

This story and more news from IPNI is available at: http://www.ipni.net/news

Agricultural Contribution to California Smog Questioned