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.

 

FROM:

Elizabeth Verhoeven, Charlotte Decock, Gina Garland, and Cristina Lazcano. 2019. “Vineyard Nitrous Oxide (N2O) Emissions.” Wine Business Monthly, January 2019, pp. 196-204.