Science & Technology in Action

11th Edition

Soil Classification

Teagasc

Soils can now be classified using the World Reference Base (WRB) for soil resources. It draws on ideas from the USDA, Russian and other systems. This system recognises 32 basic reference soil groups. Globally, the WRB system can be used as a benchmark.
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Contains the full lesson along with a supporting toolkit, including teachers’ notes.

Lesson excerpt

The World Reference Base
The World Reference Base (WRB) for soil resources is a more recently developed system. It draws on ideas from the USDA, Russian and other systems. The basic concept is to distinguish soils according to their morphology as an expression of diagnostic features (similar to the system we now use in Ireland, but with diagnostic features that apply to soils all over the world!). The detail is comparable to that of the USDA system but it omits soil climate except in cases where the climate influences soil characteristics. 

This system recognises 32 basic reference soil groups (histosols, podzols, andosols and others). Globally, the WRB system can be used as a benchmark. A soil classification derived from one system can be correlated with the WRB system and by extension with other systems. 

Quiz questions

  1. Rendzina is shallow calcareous soil. true
  2. Alluvial soil has distinct layers. true
  3. Podzol refers to infertile acidic soils typically formed in coniferous forests. true
  4. Brown Earth show a distinct profile development. false
  5. Lithosols are found in limestone areas. false
  6. A single dominant characteristic is used to divide soils into 32 Great Groups. true
  7. Eleven Great Groups are found in Ireland true
  8. Gley soils do not retain water. false
  9. Peat is always acidic. false
  10. Minerotrophic peat is usually neutral or alkaline. true