New research has revealed unsustainable levels of soil erosion in the UK. Poorly managed soil levels can affect our ability to feed the population.
The new study examined more than 1,500 existing records and found 16 per cent relating to arable land showed erosion above tolerable levels – meaning rates of soil loss are significantly greater than new soil formation.
This may not reflect the national picture, as the study has highlighted that existing studies are frequently biased towards places which have eroded in the past, explained a statement. However, the findings still show that erosion can occur at problematic levels under a range of conditions, meaning soil resources are at risk in the medium to long term.
“Unsustainable rates of erosion reduce soil fertility and can have devastating environmental impacts downstream in waterways,” said lead author Dr Pia Benaud, of the University of Exeter, in the statement. “If we don’t manage it properly in the UK and around the world, it will affect our ability to feed our growing population. Soil run-off also leads to significant extra sediment in waterways, increasing the damage to ecology and risk of flooding downstream.”
Land management affects erosion rates. For example, leaving fields bare, ploughing up and down a hill (instead of across it) or growing arable crops on steep slopes raise the risk of erosion during heavy rain. Soil types and local geography also affect erosion rates, though erosion is shown to occur on any soil that is intensively farmed, especially when rainfall is extreme.
Despite raising concerns about UK erosion above the “tolerable” rate of one metric tonne per hectare per year, the study says erosion rates in the UK are relatively low compared to the rest of Europe, demonstrating that erosion is a serious global problem.
“Analysing existing research, as we have done here, it is difficult to define what constitutes a soil erosion ‘problem’, and to know how serious an issue this is in the UK,” said Professor Richard Brazier, a co-author on the paper and Director of Exeter Centre for Environmental Resilience, Water and Waste.”What is clear, however, is that soil erosion rates of the order reported will lead to serious impacts on soil productivity if left unchecked.”
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