| More than 2 million tonnes of topsoil
from farms and forests is being eroded by wind and rain each
year, jeopardising efforts to increase food production, according
to the UK government.
The soil erosion is reducing the amount of food grown, increasing
the risk of flooding and undermining efforts to reduce carbon
emissions.
UK land has been steadily degraded by 200 years of intensive
farming and industrial pollution, warned the Department for
the Environment, Food and Rural Affairs (Defra) in a major
study
of soils. However, it said the situation is not nearly as
bad as in many Asian and African countries, where soil erosion
due to overgrazing and poor farming practices is now seriously
threatening food production.
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. Much 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 UK 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 that introducing
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."
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