Bio- Soil Erosion and Conservation

• Soil erosion

  The geological process in which earthen material is worn away and transported by natural processes such as wind or water
• Sediment


  The transported material from soil erosion
• Weathering


  The breakdown of rock but does not involve movement of the particles
• Causes of soil erosion

  • Physical erosion (e.g. landslides)
  • Erosion by water (e.g. rain, rivers, floods)
  • Erosion by wind
  • Erosion by ice (downhill movement of glaciers)
  • Thermal erosion (erosion of permafrost along a river or coastline due to changes in temperature)
• Human activities that can cause erosion

  • Altering of vegetation (eg deforestation, ploughing for agriculture)
  • Global warming
  • Some farming practices (e.g. overgrazing of animals, mono-cropping)
• Deforestation


  The purposeful clearing of forested land, usually to make space for planting crops, animal grazing, to obtain wood, manufacturing and for construction
• 2 main methods of deforestation


  • Clear-cutting
  • Slash-and-burn
• Ploughing


  The process of loosening and turning over the soil to uproot weeds and aerate the soil
• Deforestation


  Fewer trees to carry out photosynthesis, resulting in more carbon dioxide being released into the atmosphere, which contributes to global warming
• Deforestation


  Soil more prone to erosion and makes the remaining trees more vulnerable to fires due to the change from a closed, moist environment to an open, dry one
• Ploughing


  Reduced soil moisture, soil loss, disturbance of soil organisms, release of carbon dioxide from organic matter into the atmosphere, soil more prone to erosion
• Global warming


  Increases the frequency and intensity of storms which can cause soil erosion
• Types of erosion


  • Sheet erosion
  • Rill erosion
  • Gully erosion
  • Valley erosion
• Farming practices that can cause erosion

  • Ploughing
  • Mono-cropping / monoculture
  • Overgrazing of animals
  • Heavy machinery
• Effects of soil erosion

  • Reduced soil fertility
  • Soil degradation
  • Increased water pollution and sedimentation
  • Increased flooding
• Methods of erosion control

  • Building structures (e.g. gabions, hedgerows, riparian buffers, living shorelines)
  • Contour farming
  • Crop rotation
  • Strip cropping
  • Terracing
  • Applying mulch
  • Avoiding overgrazing with pasture rotation
  • Re-afforestation
• Soil is home to many organisms, purifies our water, protects against flooding (retains water), captures and stores large amounts of carbon (reducing global warming), provides nutrients for plants which can then be used for food, medicine etc.
• Soil is one of Earth's renewable resources but can be degraded if not taken care of properly.