Soil Mamagement

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• Soil Mamagement
• Christine Watson, SAC

Soil Management Christine Watson
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Outline

• Soil why bother?
• What do we mean by soil structure?
• Soil structure in the SAC crop rotations trial
• Managing soil structure- organic matter, roots,
  worms and tillage!
• Summary

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Agricultural soil functions

• Living platform for food fibre production
• Filtering buffering
• C sequestration

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The four principal components of soil
Mineral
Air
Water
Organic material
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Size of soil microbial biomass
? 9 dairy cows on an area of grassland the size
of a football pitch!
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Soil fertility management in organic farming -
what is our strategy?

• Feed the soil
• Use rotations which alternate fertility building
  and exploitative cropping
• Emphasise recycling (at a range of scales)
• Plan over time (Prevention v. Cure)

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Features to look for Compaction or uneven
distribution of residues can lead to patchy crop
development and vigour.
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Effect of cropping sequence (grass/clover,
cereals, roots) on numbers of Lumbricus terrestris
Watson, Armstrong Younie, 1999
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What causes structural change?

• Less cultivation
• More worms
• Denser root systems

• More cultivation
• Fewer worms
• Less dense root systems

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Management practices and soil function
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LIVESTOCK PRODUCE
Livestock feed Vet medicines
ANIMAL HEALTH WELFARE
ORGANIC LIVESTOCK PRODUCTION
Livestock health
Livestock type Breed Housing
SOIL FERTILITY MANAGEMENT
Livestock nutrition
Grazing management Manure management
Brought-in nutrients
Crop nutrition
ORGANIC CROPPRODUCTION
Crop choice Variety selection Crop
sequence Residue management Cultivation
WEED, PEST DISEASE MANAGEMENT
Crop health
CROP PRODUCE
Pesticides
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Some concluding thoughts.

• Healthy soil is the foundation of organic food
  production- soil structure- organic matter
  content- major and minor nutrients
• Soils are important for C sequestration and water
  quality
• Rotation design and management (especially
  cultivation) play an important role in soil
  structure and thus crop production
• Get your spade out and have a look below-ground -
  you might be surprised!

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• Thank-you!
• SAC is grateful to SEERAD, Defra and EU for
  funding organic research
• Bruce Ball
• Paddy Johnson