Drip-fertigation with plastic mulch reduces N2O emission for cotton production in northwestern China

Nitrogen fertilizer helps farmers to harvest more crops, but at the mean time may stimulate microbes in the soil to produce nitrous oxide (N₂O), an greenhouse gas which has more warming potential than CO₂.

How can we reduce N₂O emission by reasonable management of nitrogen fertilizer, and therefore cut down greenhouse gases emission?

Chinese scientists, after a two-year field trial, found that drip-fertigation with plastic mulch could effectively reduce N₂O emission in agricultural system, which is considered one of the main sources of anthropogenic greenhouse gases emissions.

Scientists conducted the field experiment in 2015 and 2016 on a sandy loam soil in Xinjiang, China with plastic-mulch, drip-fertigated cotton to determine N₂O emissions from different fertilizer N sources.

Their study showed that seasonal N₂O emissions and N-applied scaled emission factors under the drip-fertigated system were lower than those reported for other agricultural systems. “This was likely because of low soil moisture preventing appreciable N₂O emissions,” said Gao Xiaopeng, the leading researcher of the study from the Xinjiang Institute of Ecology and Geography.

Addition of urease and nitrification inhibitors with soluble urea could further reduce already low N₂O emissions from cotton fields under the drip-fertigation and plastic mulch condition, scientists found.

Results of the study were published on Agriculture, Ecosystems and Environment, entitled “Urea fertigation sources affect nitrous oxide emission from a drip-fertigated cotton field in northwestern China”.