Analysis: Action needed to preserve the nation’s soils

Everyone loves a good headline – and recent reports on the state of the nation’s soil have provided some rich pickings.

“Only 100 harvests left in UK farm soils”, “APPG uncovers more dirt on UK soils”, “Drought could degrade best agricultural land by 2050s” – these are just some of the headlines to have

graced the pages of Farmers Weekly in recent months.

But what is the real cause of soil degradation? We examine the issue, the role farming has to play and what solutions may be available.

Government reports have been sprouting like mushrooms this year, and all carry a similar message – the future of the UK’s soils is in jeopardy.

For example, research by the Committee on Climate Change (CCC) has shown more than 5m hectares of “high-grade” farmland could be downgraded over the next 40 years. The biggest effect will be

on peat soils, which will be affected by water shortages.

“The most fertile areas of Britain depend on peat topsoils,” said Lord Krebs, chairman of the CCC’s adaption sub-committee. “Three-quarters of the topsoil has disappeared within the past 150

years and that disappearance is being accelerated by climate change.”

The House of Commons Environmental Audit Committee (EAC), made up of MPs, has delivered some equally stark messages.

Its report, called simply Soil Health, was published in early June and warned that failure to prevent soil degradation could lead to increased flooding, lower food security and greater

carbon emissions. In particular, it pointed to the worrying effects of soil erosion and the decline in soil carbon levels since the 1970s.

“Soil degradation could mean that some of our most productive agricultural land becomes unprofitable within a generation,” said EAC chairwoman Mary Creagh.

The most recent report, however, has been produced by the All-Party Parliamentary Group (APPG) on AgroEcology for Sustainable Food and Farming, which collated evidence from the NFU, Soil

Association, Rothamsted Research and Cranfield University.

It suggested the UK “places little importance on soil, resulting in a worrying lack of knowledge about this vital asset,” and complained that current government policy did not reflect the

importance of soil for producing 95% of the food we eat.

“Healthy soil is vital,” said Baroness Miller of Chilthorne Domer, who led the inquiry. “Failure to tackle current problems will lead to catastrophic environmental, economic and social

breakdown. Reversing the loss of soils, along with restoring knowledge and interest in soil, are essential first steps to sustainable food production.”

The surge of interest in soil loss and degradation has been welcomed by lobbyists and scientists alike.

Prof Bridget Emmett from the Centre for Ecology and Hydrology in Wales said it was essential soils were given the priority they needed as the government drew up its 25-year environment plan

(now delayed due to Brexit).

“We have to ensure that soil is not just another add-on,” she said. “Until now, things such as biodiversity, air quality and water have been prioritised, as there are EU directives covering

these. Soil has been a Cinderella, and this must change.”

Georgia Farnworthy, policy officer at the Soil Association, said it was “hugely encouraging” that politicians were showing a commitment to the protection of soils. 

“Farmers need the right advice and best-practice guidelines for improving soil organic matter and reversing the dramatic loss of agricultural soil that has devastated the nation in recent

flooding,” she said.

In particular, she praised the acknowledgement by both the EAC and the APPG that maize growing can have negative effects on soil condition.

Meanwhile, Prof Phil Haygarth, a soil scientist from Lancaster University, has stressed the need for continued government investment in soil research.

“Soils are arguably the most complex systems on Earth, but are intimately linked to human security and the integrity of the wider environment,” he said. “Any lack of recognition of this in

terms of funding is just short-sighted and will inevitably lead to environmental and societal problems.”

The APPG report looked at a number of different factors contributing to the UK’s soil problems:

Having spelt out the problems about soil degradation in agriculture, the APPG report does offer solutions.

Maize gets a rough ride in many of the reports on soil degradation.

The most pointed comments are made in the EAC’s Soil Health inquiry, which questions the rapid growth in the UK cropped area – up 20% between 2008 and 2014, with much of this used to feed

anaerobic digesters for energy production.

The biggest danger is erosion, it explains, with widely spaced plants and compacted, bare soil inbetween being a recipe for disaster when combined with heavy rain. Water often fails to

penetrate the soil and just washes it away into watercourses, the EAC said.

But there are mitigating measures that can be taken, as spelled out by the Country Land and Business Association. “Using early-maturing varieties, sowing as early as possible and planting

under plastic can reduce the risk of harvesting in poor conditions later in the year,” it said.

“Chisel ploughing, undersowing and cover cropping can reduce run-off compared with leaving maize stubble untouched.”

Despite this, the EAC criticised the fact that maize grown for AD plants effectively benefits from a double subsidy – collecting money from the Basic Payments Scheme and a second renewable

energy premium, for example the Renewable Heat Incentive.

It therefore calls for the latter to be restructured to either exclude maize, or at least impose conditions on how it is grown.

Soil expert Prof John Quinton from Lancaster University agrees. “But it is also important to highlight the need for adopting soil conservation practices when growing other crops with a high

water-erosion risk such as potatoes, sugar beet and outdoor pigs,” he said.

In February this year the Soil Association published a seven-point plan to help improve soil health. It suggests:

The Soil Association has set a target to increase organic matter in UK arable and horticultural soils by 20% over the next 20 years as part of its Soils Campaign.

In partnership with AHDB Horticulture, it has also launched a series of workshops on soil health for horticultural growers under the GREAT Soils project, starting off in Cornwall on 21

September. See www.soilassociation.org for more details.