(1.2) Emissions
The high material input in animal agriculture results in increased emissions of metabolic products such as methane, carbon dioxide, nitrous oxide, ammonia, nitrates, nitrogen oxides and phosphates.
(1.2.1) Greenhouse gases
Animal agriculture is a major contributor to climate change, especially due to the high greenhouse gas potentials of methane and nitrous oxide, the clearing of forests, and the opportunity costs of unused carbon sinks. Depending on the calculation method, the share is 18% ([20], p.271), 28% ([37], [11], p.44) and 51% ([21], p.11). A direct comparison of greenhouse gas emissions from fossil fuels [33] and greenhouse gas emissions and carbon opportunity costs [32] from livestock farming illustrates the climate impact of agriculture with livestock.