New housing and transport infrastructure as well as climate change are all adding to the pressures on soils, explained the environment secretary, Hilary Benn. “Soil erosion already results in the annual loss of around 2.2m tonnes of topsoil. This costs farmers £9m a year in lost production. Climate change has the potential to increase erosion rates through hotter, drier conditions that make soils more susceptible to wind erosion, coupled with intense rainfall incidents that can wash soil away,” he said.
British soils contain around 10bn tonnes of carbon, half of which is found in peat habitats. Many of this habitat is under threat from climate change, mining, or poor land management. “Losing this [carbon] store to the atmosphere would create emissions that are equivalent to more than 50 times the UK’s current annual greenhouse gas emissions,” he said.
Defra’s chief scientist, Professor Bob Watson, said safeguarding soil would be “critical” if food production was to increase in the next 20-30 years. “We face many challenges of climate change, we have to produce twice as much food, it needs to be more nutritious, and if we don’t take care of our soil and our water, we will not be able to accomplish that task,” he said.
The government plans to improve soil conditions by tightening the planning system to make developers take soils into account, encouraging farmers to put back more organic matter back and preventing industrial pollution. Most soils in Britain are degraded by poor land management and the inefficient use of fertilisers, especially nitrogen.
The Soil Association, the organisation that promotes organic farming, welcomed what it said was a recognition thatintroducing large amounts of nitrogen fertiliser was not sustainable in the long term, but said that the government’s proposed measures did not go nearly far enough.
“They [the government] will not put right the huge degradation that our soils have suffered over the last 200 years, partly as a result of what the government calls intensive agricultural production. Organic farming should be acknowledged as a key approach to protect our vital soils,” said policy director, Peter Melchett.
Kathryn Alton, soil scientist and executive officer of the British Society of Soil Science, said: “The numbers of professional soil scientists in the UK has declined over time in conjunction with the loss of soil science departments. Investment is clearly needed in training soil scientists to meet these future challenges.”