Contribution of agricultural activities to greenhouse emissions (LPELC)

With regards to soil management practices, Signor et al. (2013) report that nitrification and de-nitrification processes in soil account for the highest portion of N2O production. To mitigate the increased generation of N2O in soil, Liu et al. (2015), for instance, recommended the use of organic manure in place of chemical fertilizer in temperate farmlands. From figure 7 above, enteric fermentation, a process whereby microbes in the digestive system of livestock ferment feed, and as a result release methane as a by-product that is emitted when the microbes exhale or belch (Höhne et al., 2015). To reduce the high methane emission levels from ruminants, researchers such as Albores-Moreno et al., (2018) advocate for the supplementation of the animal’s diet, by either changing the physical and chemical characteristics of the feed or using different feed additives to promote the efficiency of production.
Manure management also contributes to greenhouse gases, particularly the generation of methane when decomposed anaerobically (Pattey et al., 2005). To mitigate the production of greenhouse gases, the researchers advocated for improved manure management processes, recommending that manure ought to be stored based on environmental criteria. In the study, an experiment was conducted to determine the emission levels of manure stored in a slurry, stockpile, and aerated compost. Another measure is to decompose the manure aerobically (with oxygen) which results in little methane generation (Pattey et al., 2005). Cao et al. (2020) further recommended the acidification of manure in order to minimize the emission of ammonia at storage and during composting. However, the researchers argued that excessive acidification led to enhanced emission of N2O.