We Can Only Ignore the Soil Crisis for so Long
Published on The Telegraph 02.09.2015
By Geoffrey Lean
It's the environmental crisis nobody talks about, yet it's probably the most important one of them all. We rightly hear a lot about the dangers of air and water pollution, of loss of species, and of climate change, but the warnings rarely come – literally – down to earth.
Yet just a handspan of topsoil lies between us and oblivion, a veneer of fertility normally just six to ten inches deep overlying the unforgiving rock of the continents. And, worldwide, we are annually losing at least a staggering 30 billion tons of it, while an area three times the size of Switzerland goes out of production forever each year.
Just a handspan of topsoil lies between us and oblivion.
This tragedy, it is true, is mainly happening in developing countries. Our relatively mild climate and young soils, relatively recently emerging from an ice age, mean that we escape the worst. But a new, unpublicised, shocking parliamentary report nows shown soil degradation to be a serious issue in Britain too.
Every year, says the report by the Parliamentary Office of Science and Technology
, it costs us up to £1.4 billion a year. But we are doing virtually nothing about it.
The two main problems are loss of the organic matter that gives soil much of its fertility, and its compaction by livestock and heavy agricultural machinery. The first is particularly bad in East Anglia, where the report says naturally peaty soil, drained for agriculture, is being lost at an alarming average rate of up to two centimetres a year. In some places earth that was once a full four metres deep has “entirely disappeared”.
The loss of such organic matter, wherever it occurs, denudes the soil of richness and diminishes its ability to hold water and retain carbon. If Britain were to lose just one per cent of the carbon stored in its soil each year, the effect would equal its annual emissions from burning fossil fuels, accelerating climate change.
The presence of worms can help the prevention of soil erosion by improving soil structure and drainage Photo: PA
Compaction, which makes it hard for rainwater to sink into the soil – and easy for it just to run off the land – has increased flooding, particularly in the South West. In all, its contribution to inundation, the report concludes, costs the country an average of £233 million a year. Fields growing maize are particularly prone to it: three quarters of them are affected and up to half the sediment clogging up rivers may come from growing the crop.
Sure enough, there are signs of trouble on the horizon. After many years of steadily increasing, wheat yields have stayed much the same for the last eight, suggesting that diminishing soil fertility may be to blame.
Quite a lot can be done to restore soil heath – from adding organic fertilisers to planting trees nearby, from rotating crops more slowly to growing clover and vetch and other “green manures”. But, though the Government is theoretically committed to ensure Britain's soils are managed sustainably by 2030, little is being done.
There is, the report reveals, not even any “UK wide monitoring of changes in soil health
”. Nor is there any specific EU legislation on soils: indeed, an attempt to bring in a directive, some years ago, was repeatedly blocked by Britain, among other countries. It is, indeed, the impending crisis no-one seems to want to notice, crucial though resolving it may be to our wellbeing.