A UN report has suggested a "fart tax" on cattle… could help tackle greenhouse gas emissions from livestock… the report from the UN's Food and Agriculture Organisation (FAO) calculated that the world's 1.5 billion cattle and buffalo... and almost one billion pigs produce methane emissions equivalent to about two billion tons of CO2 every year, or six per cent of all annual greenhouse gas emissions… The report argues that market-based policies, such as taxes and fees for natural resource use, "should cause producers to internalise the costs of environmental damages caused by livestock production". It also recommends "subsidies that directly or indirectly promote overgrazing, land degradation, deforestation, overuse of water or GHG emissions should be reduced or eliminated"…