The Effect of Nitrification Inhibition on Nitrous Oxide Emissions and Soil Nitrogen Levels in Fields Applied with Liquid Manure at Various Fall Timings

Abstract

The goal of this study was determine if nitrification inhibition, using nitrapyrin (eNtrenchTM), and timing of manure application had an effect on nitrogen losses from corn fields. This study was conducted at the Elora Research Station, Elora, Ontario from October 2016 to October 2018. Liquid hog manure was applied at four fall timings and one spring timing with and without inhibitor. Soil samples and gas samples were collected periodically throughout the fall and growing season. Inhibitor addition had no significant effect on mineral nitrogen soil content or nitrous oxide emissions. Soil nitrogen and cumulative emissions were responsive to fall application timing. There was a significant interaction between the use of inhibitor and application timing on cumulative nitrous oxide emissions. This interaction showed higher cumulative losses of nitrous oxide from manure applied without inhibitor in late April. Based on these results, fall application would be best in mid-fall (mid-October to mid-November).