atmosphere acts as a source for nitrous oxide through the oxidation
of ammonia (NH3). In total, atmospheric
ammonia oxidation is thought to be responsible for about 600 thousand
tonnes of atmospheric nitrous oxide-N each year.
The primary sources of atmospheric ammonia are man-made, with
the largest increases in emissions in recent decades being due
to increased global livestock farming.
Ammonia is emitted from both solid and liquid livestock waste
and can also induce nitrous oxide production in soils by deposition
after its initial release. Plumes of ammonia can often be detected
arising from intensive livestock rearing facilities, such as poultry
and pig farms.
Livestock are the largest source of atmospheric ammonia emission,
with areas of extensive animal rearing giving 'hot spots' of ammonia
production as described above. Fertilizer application and agricultural
chemical use are also significant sources of atmospheric ammonia,
as is fossil fuel powered transport.
Potential for control
The ever increasing demand for cheap meat on a global scale has
led to a rapid increase in large scale intensive livestock rearing.
Such facilities give rise to large amounts of ammonia, some of
which then contributes to the atmospheric nitrous oxide burden.
Better livestock rearing and land use practices may substantially
reduce such emissions and, in the long term, more extensive farming
and higher meat prices are likely to be required.