Summary: | This study aimed to determine the emissions of methane (CH<sub>4</sub>) and nitrous oxide (N<sub>2</sub>O) from seven Tunisian livestock species and their evolution over eleven consecutive years (2008–2018). The species of animals used were cattle (dairy and others), sheep, goats, camelids, horses, donkeys and mules, and poultry. The estimations of CH<sub>4</sub> and N<sub>2</sub>O emissions were based on the Intergovernmental Panel on Climate Change (IPCC) guidelines for national inventories, using Tier 1 and Tier 2 approaches, with its default emission factors (EFs). The Tier 2 approach was applied only for the calculation of EF to estimate CH<sub>4</sub> emissions related to livestock manure management. CH<sub>4</sub> emission represented more than 92% of the total greenhouse gas (GHG) from livestock emissions. Moreover, 53% of the total CH<sub>4</sub> emissions from livestock were derived from cattle, followed by sheep, goats, other mammals (camelids, horses, mules, and donkeys), and poultry. During the period covered by the study (2008–2018), a slight and continuous decrease of both livestock population and total GHG emissions was observed, mainly in terms of CH<sub>4</sub>. In mammals, CH<sub>4</sub> emissions were greater than N<sub>2</sub>O emissions, whereas in poultry, N<sub>2</sub>O emissions were up to 2.6 times greater than CH<sub>4</sub> emissions. The aggressive drive of the government to increase cattle and sheep production might affect CH<sub>4</sub> emissions in the future. Therefore, periodic estimations of GHG emissions from livestock are required to follow the time trends for more rational decision-making regarding livestock and GHG emissions policies.
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