Greenhouse gas emissions from agriculture, which includes cattle grazing, have been increasingly recognized as an extremely important anthropogenic source. The primary focus of this body of work was to investigate the impact of cattle ranching on these emissions in British Columbia in order to determine the overall carbon footprint. To accomplish this task, the grazing activity that is currently occurring within the Lac Du Bois grasslands of British Columbia was examined. Particular emphasis was placed on identifying point sources and removals of greenhouse gas emissions from cattle ranching. Enteric methane emissions were empirically measured at two elevation gradients in the spring and fall of 2010, and it was found that the cattle emitted on average 370.01 L CH4/day; these measurements done on native grasslands, are comparable to similar work done by others on tame pastures. The total digestible nutrients (TDN) from the pastures in the study area were determined to be 65.22% of dry matter; which is the default value used by the International Panel on Climate Change (IPCC) in their methodology for determining overall emissions. Utilizing this information, a whole system life cycle analysis (LCA) was conducted on cattle grazing in Lac Du Bois. Equipped with a validated model based on our empirical measurements, the following grassland improvement strategies were evaluated: reducing stocking density; and reseeding/interseeding grass and legumes with and without synthetic fertilizer additions. Of the scenarios modelled, reseeding was the most effective at reducing the carbon footprint of cattle ranching on the Lac Du Bois grasslands. Reseeding initiatives could theoretically result in soil carbon sequestration rates of 2.12 Mg CO2 eq/ha. Finally, the potential opportunities for BC livestock ranchers to participate in carbon markets were reviewed. While opportunities exist, cattle ranchers will have to adapt or develop applicable protocols in order to participate in carbon markets. Diet manipulation and pasture rejuvenation initiatives may offer the best carbon offset potential. It is recommended that a combination of reductions and removals should be implemented in the future to reduce the overall carbon footprint of cattle ranching in British Columbia.
