Vineyard Nitrous Oxide Emissions Fast Facts
· The greenhouse gas effect of nitrous oxide is 300 times that of carbon dioxide.
· Approximately 60% of nitrous oxide emissions are attributed to agriculture, putting pressure on agriculture to reduce emissions.
· During the natural decomposition and cycling of Carbon and Nitrogen the greenhouse gasses carbon dioxide, methane, and nitrous oxide are produced.
· Nitrous oxide is a natural byproduct of the nitrification and nitrification cycles.
· Vineyards produce nitrous oxide emissions similar to other Mediterranean crops- about 1 lb./acre per year.
· Drivers of increased nitrous oxide emissions:
o High soil moisture
o Availability of nitrate-nitrogen from fertilizer
o Availability of carbon from tillage and crop residue
o Higher microbial activity from compost
o Changes in soil pH from fertilizers or soil amendments
o Warmer soil temperature
· Soil and fertilizer management affect the amounts of these gasses released from the soil.
· High nitrous oxide emissions occur in the tractor alley after rain in the fall and freeze/thaw events in the spring.
· High nitrous oxide emissions from the vine row occur during fertilization and after rain.
· Approximately half of vineyard nitrous oxide emissions occur during the non-growing season.
· Vineyards with cover crops have higher emissions than tilled soil. Benefits of cover crops outweigh higher emissions, howeve).
· The largest releases of nitrous oxide are after rain events, especially the first rain event of the fall or winter, regardless of floor management.
· To reduce emissions, avoid working the soil in the tractor alley when rain is expected.
· To reduce emissions, minimize floor management in the fall.
· New data on this topic is still forthcoming.
Elizabeth Verhoeven, Charlotte Decock, Gina Garland, and Cristina Lazcano. 2019. “Vineyard Nitrous Oxide (N2O) Emissions.” Wine Business Monthly, January 2019, pp. 196-204.