Soil erosion is the degradation of soils caused largely by the result of human interference and a deep concern amongst UK environmental departments. While soil erosion can occur naturally, the result of human interference has hugely impacted the issue. Defra, The Department for Environment, Food and Rural Affairs have submitted a report to help tackle this issue along with their strategy to safeguard soil in the UK [1] (Defra) (2020).
This report gives a comparatively short summary of this expansive problem, the causes, along with the government’s solutions to safeguard soils on arable land. Discussing carbon loss due to ploughing, nutrient loss caused by intensive farming, and the impact on arable soil due to the rapid growth in urbanisation. In the following sections I will discuss the problem of soil erosion if left unchecked, its causes and the solutions to adopt better practices to improve farmland soil.
As Soil Organic matter (SOM) is made up of over 50% carbon the constant disturbance caused during tilling and cultivation is a serious cause for concern according to The Agricultural and Horticulture Development Board 2 [2] (AHDB) Zero tillage is encouraged by the UK government to protect the environment as damaged soil release greenhouse gasses during this process. [3] (Bhogal, et al) However according to a Farmers Weekly report, as of 2023 only a mere 3% of the UK arable area is farmed using zero tillage, which is much lower than other parts of the world. In the article Anthony Pope a Consultant/Project Director for farmers in UK and Internationally, argues that more farmers should really consider this approach [4] (Farmers Weekly) (2015) This is also supported by a report from DEFRA stating that 50% of organic matter could be replenished in 20 years by putting into practice the use of no till farming and to further protect the land with cover crops, sown in early summer and left over winter after harvesting. [5] (DEFRA) (2023)
Along with carbon loss from ploughing, land is also being dramatically eroded due to poor land management and the intensive farming of cereal crops, of which make up 70% of arable land. According to The Department for Environment, Food and Rural Affairs 6 [5] (DEFRA) (2023) one of the main cereal crops maize, increased by 7.5% in 2023 and is now being grown on 218 thousand hectares of land. Maize crops cause many issues as it grows incredibly fast, the stems are sown spaced widely apart, and the roots do not set in deep. The heavy foliage means little light reaches the ground and this combination means water is not being draw down and instead runs off the land. After cultivating the government advises farmers to leave the stubble left from maize harvest as this benefits wildlife, but it is an ineffective method of protecting soils. It is argued that the establishment of an effective cover crop would protect the land from erosion and carry financial benefit for farmers. It has been estimated that forty kilos of nitrogen, the equivalent to 30lb per hectare would be retained if cover crops were established following maize harvest. A quote from [6]The Soil Association (2015: 16) points out that, ‘…some farmers are now seeing the advantages of under sowing maize with a green winter cover crop…’. This is because a correct balance of nitrogen and phosphates are needed to support soil structure, hold in water and prevent carbon being released into the atmosphere. A report by [1] DEFRA (2020: 10) analysis showed that ‘A comparison of soil nutrient balances (in kg per hectare) from the year 2000 to 2019 shows a 24% decrease for nitrogen and a 46% decrease for phosphate’. In contrast, a journal featured in the National Library of Medicine [7] Zhang et al. (2022: 7) shows that research during 2019–2020, recorded higher nitrate concentrations in select fields in early winter where long-term improved grassland were ploughed and sown with winter wheat cover crops. For a limited time, these concentrations even exceeded the recommended threshold values. Introducing these sustainable farming practices would have the additional benefit in preventing run-off into urban areas.
Continued intensive farming can impact the health of soil if not managed correctly. In addition, increased urbanisation has also affected soil health, caused by farmers struggling financially and selling off greenfield sites for housing. This also mean they have less land and forcing them to farm more intensively in smaller areas. A report from the National History Museum states that ‘it’s not just agriculture that is to blame: increasing urbanisation also has a negative impact. The widespread use of tarmac and concrete prevents water from being absorbed into the ground. This results in the death of millions of microorganisms and can lead to water runoff in other areas where it may cause flooding and erosion.’ [8] (National History Museum) When run off does occur this leads to the damaging pollution of waterways which become full of pesticides and herbicides.
In the UK there is an acceptance that flooding is increasing year on year and water quality is poor and largely caused by run off [9] (Direct Science, Hutchins and Miller, 2017).
‘Urban life can create a false sense of separation between people and nature. In reality, a complex network of cause and effect connects the human, built and natural elements of the environment, within and between urban and surrounding rural areas, locally and globally. Changes to one part of this system may affect others in expected or unexpected ways.’ [10] (Environment Agency, 2023).
On National World Soil Day 5th December 2023 The UK Government published Defras latest report ‘Soil Health’ where they lay out the framework and immediate actions needed to initiate programmes to resolve these issues. Opening in their summary with an understanding that it is important to layout a framework to mitigate the impact. [5] (DEFRA) (2023) Soil erosion and degradation is not only a potential risk to food production capacities but also human health as ‘Poorer quality foods may also be linked to worse gut microbiomes and chronic diseases, which incur serious cost to healthcare systems. It has also been estimated that “75% of antibacterial agents and 60% of new cancer drugs approved between 1983 and 1994 had their origins in the soils, so the loss of biodiversity in soils could inhibit future drug development.’ [5] (DEFRA) (2023) Even at the start of 2024 there has been major incidents declared with hundreds of nationwide flood alerts in place, rivers bursting their banks, trainlines and roads being closed, Many people needing to evacuate their homes, vulnerable and elderly people at risk, not to mention financial cost to home owners and businesses. The government has been asked to do more to course correct this issue, but with limited data there needs to be a better framework set in place for uk soil management. We have a damaged ecosystem and as UK soils currently only hold around 9.8 billion tonnes of carbon emission, this is just half of our soil’s storage potential. [5] (DEFRA) (2023).
Solutions which need to be set in place include better farmland managements and farmer educational support. Zero soil waste in the construction industry would need to be tackled and better use of brownfield sight rather than destroying Greenland’s. Regulations set in place to prevent soil contamination, because once the soil is contaminated it struggles to recover naturally if ever. In Defra reports 2023 says that’s ‘Natural England told us that soil science needs to be represented throughout the education system to address the “soil skills gap”. More soil health related further, and higher education courses may help and also be useful for wider society by, for instance, encouraging communities and local organisations to become advocated of healthy soil in planning or enabling sustainable consumer choices.’ [5] (DEFRA) (2023, 43). The evidence is quite clear that while soil erosion can occur naturally, the result of human interference has hugely impacted the issue, and while the understanding of the importance of soil health has been known for many years, a lot is being said but little is being done. It is only in recent years that the true scale and magnitude of importance of soil health has become apparent and the key to change is through education throughout industry and society. How can there be change without knowledge.
Reference list
1. DEFRA, 2020, Agricultural in the United Kingdom.
[available here]
2. What Soil Organic Matter is and what it does.
[available here]
3. The effects of reduced tillage practices and organic material additions on the carbon content of arable soils.
[available here]
4. Farmers Weekly, Many UK Growers Missing out on the Benefits of Zero Tillage.
[available here]
5. DEFRA, 2023, Agricultural land use in England.
[available here]
6. THE SOIL ASSOCIATION, 2015, Runaway Maize.
[available here]
7. National library of Medicine. Diffuse water pollution during recent extreme wet-weather in the UK: Environmental damage costs and insight into the future.
[available here]
8. Natural History Museum. Soil Degradation: the problems and how to fix it.
[available here]
9. Science Direct. The impacts of urbanisation and climate change on urban flooding and urban water quality: A review of the evidence concerning the United Kingdom.
[available here]
10. Environment Agency. The state of the environment: the urban environment.
[available here]