Economists and agricultural scientists tend to be optimistic in their assessment of the world's ability to support its rapidly growing population, whereas environmentalists tend to be pessimistic, and it’s not difficult to see why.
Technology has been used to improve agricultural yields in developed countries since the end of the Second World War, and new high-yielding seed varieties, chemical treatments and irrigation technology are now widely used across the developed and developing world. The environmental impact of intensive agriculture is widely acknowledged. What’s more the growth of crops and rearing of livestock, as well as its global transportation, requires energy, and with that comes carbon and other greenhouse gas emissions, prominent among them methane and nitrous oxide.
Economists and agricultural scientists tend to be optimistic in their assessment of the world's ability to support its rapidly growing population, whereas environmentalists tend to be pessimistic, and it’s not difficult to see why. Technology has been used to improve agricultural yields in developed countries since the end of the Second World War, and new high-yielding seed varieties, chemical treatments and irrigation technology are now widely used across the developed and developing world. The environmental impact of intensive agriculture is widely acknowledged. What’s more the growth of crops and rearing of livestock, as well as its global transportation, requires energy, and with that comes carbon and other greenhouse gas emissions, prominent among them methane and nitrous oxide.
It would be wrong to pinpoint agriculture as the chief culprit in the greenhouse gas debate. In fact it’s a relatively small player, although it does present particular challenges since methane and nitrous oxide are much more powerful greenhouse gases than carbon (about 20 and 300 times respectively) and emissions of these gases are strongly related to levels of production. Carbon dioxide emissions from transport in the UK are far greater than those from agriculture and they increased by 12% between 1990 and 2006, according to Defra figures (The environment in your pocket, Defra, 2008). A mere 7% of UK emissions come from agriculture*, but that is not to say that nothing should be done. The Government has a range of no fewer than 68 sustainable development indicators by which it judges its progress towards meeting the targets it set for itself in the 2005 Sustainable Development Strategy. In order to succeed, it will need to address what the Hampson report of 2006 called the “negative externalities” of agriculture, including flood risk, eutrophication, soil acidifiation and diffuse pollution. Agriculture is responsible for around 37% of methane emissions in the UK, and around 67% of nitrous oxide, so if we include them among these negative externalities, where should action be prioritised?
An analysis of UK livestock reveals that the beef and dairy industries between them account for over half of emissions of these two greenhouse gases, with the beef industry most culpable at 32% and dairy in second place at 23%*. Sheep contribute a further 18%, on a par with arable agriculture, with the pig and poultry industries relatively marginal contributors at 9% in total. As one might expect then, the ruminants attract the spotlight, and here is where there is greatest scope for reduction, though technically, it won’t be easy. Scaling back numbers of animals (or simply persuading people to eat less meat) is not guaranteed to be politically popular – and the impact on landscape management, particularly in upland areas, poses further challenges – so as a starting point, what about an examination of the structure of the “big two” cattle-based industries to identify lessons that meat can learn from milk? If production efficiencies correlate with lower methane and “nox” emissions, then a more productive, energy-efficient, beef sector has got to be good news. The big question is whether the beef sector can deliver improved efficiencies of the necessary scale – and consequently a better environmental footprint – with its existing structures, land occupation patterns and associated management practices? With some lobbyists calling for farming to be carbon neutral by 2020 it is a question that will need careful thought and, potentially, a tearing up of the rule book on how we farm UK beef.