The recent COP 21 agreement (Paris – December 2015) has, once more, highlighted climatic and global warming issues. Statistics revealed that, in France, agriculture contributes to 21% of the national total amount of greenhouse gas (GHG) emissions (2011). What about the tobacco crop impacts on GHG?

France Tabac ordered a study conducted by ARVALIS (2013) to have an idea of the tobacco crop contribution towards GHG. EGES^® is a tool based on the life cycle analysis method to calculate the balance between inputs (fertilisers, chemicals, fuel, etc.) and output flows (yields) estimated on tobacco fields and the whole crop rotation. The study was conducted on two representative farms (air-cured Burley and flue-cured Virginia) and compared to a soft wheat reference. All data was converted into CO₂ tonne equivalency using international and standardised databases.

The first results show that:

• on the field scale, one hectare of flue-cured tobacco has the same footprint as soft wheat, whereas Burley emissions are twice as high, due to fertiliser amount and to nitrogen demineralisation, which is an important source of N₂O, a gas with a global warming potential 300 times greater than CO₂.
• if the curing process is added, the flue-cured tobacco footprint is widely penalised due to the fossil gas used. In this case, the curing process has a higher impact than the field one. At the same time, the air-curing process does not contribute to GHG emissions, and finally, explains why Burley has a total impact lower than the flue-cured tobacco.

Thanks to these results, France Tabac and ARVALIS are able to focus on the main GHG sources to implement trials, training or action plans to improve critical crop operations.