Introduction
Sandy, silty and low organic matter soils are most vulnerable to water erosion but all soils can be at risk in intense periods of rainfall.  Bare soils, slopes and compacted soils are more prone to water erosion.

Increasing organic matter can improve soil stability and water infiltration, helping to minimise the risk of erosion.  On sloping fields planting direction  should be planned to avoid channelling water down slopes. Grass strips and field margins can be helpful to reduce erosion.

Water erosion is made worse by poor soil structure which in turn causes loss of pesticides and nutrients, thereby reducing soil fertility.

Water erosion as it applies to different sectors...

Potatoes
The biggest risk of soil loss occurs on sandy and light silty soils as they have an inherent low stability.  The risk is particularly severe where rows or beds are planted up and down slopes.  As well as the environmental damage caused by nutrient and agrochemical loss to water there is increased risk of crop greening which reduces crop quality and saleable yield. 
Where irrigation is used it should be applied evenly at moderate rates, with appropriate droplet size (not too big) in order to minimise surface sealing, water runoff and erosion. 
Techniques to hold back water such as using tied ridges or forming indentations in the row/bed surface can help reduce erosion.  Water infiltration can also be improved by running a tine through the furrow bottom after planting.

Horticulture
Light soils are most at risk but all soils can be prone to water erosion in intense periods of rainfall. The leaching of pesticides and fertilisers and damage to soil structure hinders growth and affects crop yield and quality.

Measures that can be taken by growers include:

• Planting crops along contours
• Increasing organic matter by the use of composted material
• Avoiding compaction
• Carrying out risk assessments of fields prone to water erosion prior to cropping
• Avoiding fine seedbeds where possible, if they will cap or slump 
• Using cover crops (e.g. sowing cereals on pre-formed beds destined for salads to stabilise soils through the winter)
• Maintenance of field drainage systems

Cereals and Oilseeds
Sandy, silty and low organic matter soils are vulnerable to water erosion. Bare soil in winter encourages water movement across soil surfaces and erosion can occur on any slope. Compacted soils are more prone as they prevent infiltration of rain. Surface and incorporated residues add stability to soil, aid infiltration and reduce the risk.

Water erosion has a strong economic impact on affected land and off-site on the surrounding civil and public infrastructure. Also, crop yields in eroded soils are lower than in protected soils as erosion reduces soil fertility and water availability.  Leaching of nutrients and pesticides into surface and ground water causes eutrophication and poses a threat to aquatic organisms and impacts on drinking water quality. Loss of soil and agrochemicals is not only a source of pollution but is also a waste of valuable resource.

Off-site problems, caused by soil sediments transported in surface water from eroded agricultural land, may contribute damage to roadways and sewers, drainage disruption and siltation of harbours and channels, loss of reservoir storage, disruption of stream ecology and increased water treatment costs.
Most erosion events in the UK occur in winter cereal cropping (because these are the major crops) and are associated with tramlines, valley floor features and a lack of early ground cover. This not to say that the worst cases occur in winter cereal cropping.

Sugar
Existing compaction must always be removed before establishing the crop and cultivations timed to avoid creating new compaction. Stubble or residues from previous crops should be left for as long as possible before drilling.   Drilling directly into loosened rows in cereal stubbles or sprayed off cover crops will also minimise water erosion.

If ploughing is needed, do not overwork the land and drill directly into furrow pressed land. If safe to do so, and harvesting will not be compromised, drill across the slope but avoid wheelings leading to valley features where water can be concentrated. On those few fields where irrigation is used, do not over irrigate. On land where water erosion is known to occur post cropping, establish the next crop as soon as possible or rough plough or tine the land so that rain can seep away.

Dairy
Forage maize production is the major cause of runoff and erosion on dairy farms, with water channelled along maize drill rows after planting and wheel marks left by harvesting machinery.  Farmers should consider using early maturing maize varieties to allow earlier harvesting and the chance of sowing winter cereals or a cover crop following the harvesting of the maize.  Poaching is also a problem with damaged grass cover allowing soil erosion with soil particles washing off, especially during periods of heavy rainfall.

Pigs
Where pigs are kept on slopes, surface runoff and erosion can occur.  As the ideal soil type for outdoor pigs is free draining, and herds are predominantly sited on light sandy soils, sloping sites with sandy soil, particularly where the soil organic matter content is low, are at high risk from erosion.  Furthermore, the excreta deposited in fields accumulates a large amount of nitrogen and phosphorus within the soil surface which is at risk of entering sensitive sites such as watercourses and roads if erosion occurs.  Farmers are well aware of this significant potential problem and are encouraged to compile and implement a soil management plan to identify the areas at greatest risk and take mitigating action.

Levy Board Information
BPC included in coverage for soil management plans
BBRO
Beet growers guide, sugarbeet portal, Beet review magazine
MDC
Grass+ chapter 10

Web links to other organisations
www.SMI.org.uk  - publications
www.Environmentsensitivefarming.co.uk  - ppt presentations on soil management for soil erosion causes and consequences, potatoes, outdoor pigs, crop specific guidelines, GAEC (2006)
word doc describing options for autumn drilling to prevent soil erosion plus preventing pollution from pig and chicken manures and slurries (2005)
Defra - http://www.defra.gov.uk/ENVIRONMENT/land/soil/information/publications.htm
Controlling soil erosion: a manual for the assessment and management of agricultural land at risk of water erosion in lowland England, revised 2005 (PB4093) available online

Publications available in hard copy:

Defra

• Controlling soil erosion: a manual for the assessment and management of agricultural land at risk of water erosion in lowland England, revised 2005 (PB4093).
• Controlling soil erosion: an advisory booklet for the management of agricultural land, 1997 (PB3280)
• Controlling soil erosion: an advisory leaflet for preventing erosion caused by grazing livestock in lowland England, 1999 (PB4091)
• Controlling soil erosion: a field guide for an erosion risk assessment for farmers and consultants, 1999 (PB4092)
• Controlling soil erosion: an advisory leaflet for preventing soil erosion in the uplands, 2001 (PB5820A)
• Controlling soil erosion: an advisory leaflet for preventing erosion by outdoor pigs, 2001 (PB5820C)
• Controlling soil erosion: incorporating former advisory leaflets on grazing livestock, wind, outdoor pigs and the uplands, 2005

SEPA - SAPG review of agricultural pollution including role of soil protection (2003)
SMI - Improved soil management for agronomic and environmental gain

Link to publications page

Link to training page