Soil structural decline

Impact

Soil structure describes the arrangement of soil particles into larger aggregates of varying size and shape.  Soil structure also encompasses the pore spaces between soil aggregates.  Soil organic matter assists in the maintenance of soil structure.  Structure is an important soil property with respect to soil stability, bulk density, porosity and infiltration.  Well-structured soils tend to be more stable and as such are less susceptible to erosion and provide better conditions for plant growth.  Soil disturbances, such as tillage and land clearing can lead to soil structural decline.  Soil compaction is a specific type of soil structural decline.

Suggested indicator: Soil structure+

Soil structural decline may be associated with:

Potential associated impacts

 Suggested indicators+
Reduced efficiency of soil nutrient cycling and reduced soil air and water leading to decline in plant growth
  • Soil chemistry
  • Plant available water
Reduced microbial activity and reduced organic matter decomposition
  • Soil life
  • Organic litter
Reduced water infiltration and increased surface sealing leading to rapid and excessive runoff under some circumstances
  • Soil infiltration

Increased potential for soil erosion leading to:

  • reduced water quality if eroded sediments are washed into waterways
  • Hillslope erosion
  • Gully erosion
  • Wind erosion
  • Fine sediment in water
  • Phosphates in water
  • Nitrates in water

+ Descriptions of indicators (PDF, 76K)* provides a brief description of each indicator including techniques and purpose.

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Last updated 7 September 2010

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