Another useful tool is the International
Wine Industry Greenhouse GasProtocol and Accounting Tool
(
website),
developed by Wine Institute and international partner organizations,which allows the calculation of estimated
vineyard and winery GHG emissions.
Because these tools are in development,
and impacts of sitespecific
factors
such as soil type, climate, rootstock,
grape variety, and vineyard ageon GHG emissions are not fully understood,
it currently is not possible to definitively evaluate the emissions forevery management practice.
However, use of the tools provides understanding about how carbon accounting works. Nevertheless,
a number of vineyard activities clearly affect GHG emissions, for which current
understandings and mitigation tactics are described below.
Fossil Fuel Combustion
Combustion of fossil fuels during the operation of tractors, ATVs, irrigation pumps,
and other farm equipment often constitutes a large source of the vineyard GHG footprint. Different fossil
fuels are associated with different amounts of GHGs.
However, all fossil fuels, including cleaner burning
natural gas, combust to produce significant amounts of CO2 and variable quantities of other GHGs like N2O.
Although it has a greater energy content per unit volume, diesel produces
more CO2 and N2O than gasoline,
natural gas, or propane. Reducingfuel usage is one of the most obviousand effective ways to reduce the vineyard
GHG footprint. Any reduction intractor passes, for example, diminishesthe carbon footprint.
Nitrogen Fertilizer applications
Another important source of vineyard
GHG emissions is the use of
nitrogen fertilizers. When any nitrogen is added to soil, some of the applied nitrogen can be converted to N2O.
This can happen to any nitrogen containing additive including synthetic fertilizers
(nitrate and ammonium) and organic materials (green manures and pomace).
All N2O production associated with vineyards results from soil microbes using the nitrogen instead of the vines. Moreover,
some added nitrogen can leach into ground water and subsequently be converted to N2O. Minimizing N2O emissions may be challenging.
