Soil erosion control measures in UK agriculture

The study focused on cultivated arable land in the UK, considered at highest risk of soil erosion among all land uses. 

The total agricultural area in the UK was estimated at 18.3 million hectares in 2009, with approximately 17 per cent (3.1 million hectares) affected by soil erosion. 

The analysis acknowledged significant spatial and temporal variability in erosion rates and costs, noting that 'critical source areas' within catchments contribute disproportionately to erosion-related impacts due to hydrological connectivity with watercourses.

To assess the cost-effectiveness of erosion control measures based on an ecosystem services approach, enabling better-informed decisions about which measures to promote and incentivise in UK agriculture.

Challenges addressed

The measures address environmental management, with soil erosion on agricultural land as the core challenge.

Costs of NbS

The study assesses erosion control measures that could be applied across about 3.1 million ha of erosion-prone farmland in the UK. Costs per hectare are low. Mulching with straw costs about EUR 139 per ha in materials, labour and machinery. Riparian buffer strips of 6 m cost about EUR 47 per ha, plus around EUR 26 per ha in lost crop production. High-density planting adds about EUR 7 per ha in extra seed, and tramline management, breaking up compacted wheel tracks, costs about EUR 28 per ha (2023 prices).

The measures keep fertile topsoil on the field, protecting yields and reducing sediment and nutrient pollution downstream. Mulching and buffer strips also store carbon in the soil. Once these on-site and off-site benefits are counted over five years (3.5% discount rate), all four measures yield a positive net present value for society: about EUR 518 per ha for riparian buffer strips, EUR 424 per ha for mulching, EUR 340 per ha for tramline management and EUR 187 per ha for high-density planting (2023 prices, moderate estimates). Results vary with local conditions and should be checked at farm or field level.

Benefit–cost ratio

BCRs are at least 3.0 for mulching, 2.85 for riparian buffer strips, 1.48 for high-density planting and 1.42 for tramline management, rising to between 6 and 18 under more favourable assumptions. For the farmer alone, however, these measures bring little or no financial return, which explains why uptake without compensation is low.

The study applied a four-step methodology: 

•  establishing the economic baseline cost of soil erosion on ecosystem services at national level; 
•  determining financial costs and benefits of control measures at field level, including investment costs, maintenance costs, and production losses; 
•  determining effectiveness of measures on soil erosion processes (run-off, soil loss, phosphorus loss);
•  calculating economic NPVs including ecosystem service impacts. 

Measures were ranked by cost-effectiveness using formulas accounting for both economic value and percentage reduction in soil loss.

None available

Study overview

This study assessed the cost-effectiveness of various erosion control measures for arable agriculture in the UK using an ecosystem services approach. The research addressed the challenge that many erosion control measures result in negative financial returns for farmers, explaining their reluctance to implement such measures without compensation or incentives.

An estimated 2.2 Tg of arable topsoil is lost annually in the UK due to water erosion, with rates varying between less than 1 and 20 Mg/ha/yr across different areas. These erosion rates significantly exceed soil formation rates of 0.3–1.4 Mg/ha/yr for most of Europe. Soil erosion causes both on-site impacts (damage to crops, loss of nutrients and fertile topsoil, land management difficulties) and off-site impacts (blockages of drains and watercourses, water pollution, damage to infrastructure from muddy floods).

The economic appraisal followed Defra's ecosystem services framework, quantifying and valuing impacts on ecosystem services including food and fibre production, carbon sequestration, water quality, flood regulation, and infrastructure protection. The study evaluated 24 different erosion control measures across categories including agronomic practices (cover crops, mulching, crop rotation), structural measures (buffer strips, earth banks, swales), and management changes (reduced tillage, tramline management, land-use change).

Analysis showed that off-site costs of soil erosion (£237–£458 million nationally) far exceed on-site costs (£11 million), with flood damage, siltation and eutrophication representing the biggest costs. However, most erosion control measures show negative financial net present values (NPVs) at field level, even with agri-environment payments included. This creates a market failure where socially beneficial measures are economically unviable for individual farmers.