The enteric methane from sheep during the on-farm stage
emerges as the hotspot for the meat and wool life cycle, which
could be reduced by modifying diets, or in the future the genetic
selection of animals that produce less methane.
This study also found thatGHGemissions fromwheat production
(when the sheep methane emissions are included) are 187% higher
for the case study in Hamilton, Victoria than in Cunderdin,Western
Australia, due to the significantly higher N2O-N emissions (and
rainfall) in Hamilton and grazing activities. In addition, the research
highlights the significantly higher GHG impact of sheep and pasture
enterprises relative to wheat production in Australia, albeit in
comparing results across two different agricultural regions. The
research also raises the question of the complexity of accounting for
individual systems in a mixed enterprise farming system. However,
GHG emissions per kg of grain from the pre-farm stage of wheat
production in Hamilton, Victoria is significantly lower than the
emissions from the same stage of wheat production in Cunderdin,
because nitrogen fixation of the sub-cloverwas applied in the wheat
plot in Hamilton in order to avoid the use of urea.