Australian Soil Classification

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The Australian Soil Classification is the system used to describe and group soils in Australia. The system comprises a number of related documents produced by the Australian Collaborative Land Evaluation Program, a division of the CSIRO, and is the latest iteration in a long line of local classification systems.

[edit] The Australian Soil Classification (Revised Edition)

Chief among the documents used to classify soils in Australia is this publication, also known as the 'grey book'. Authored by Raymond F. Isbell, it contains a key used to group soils into one of fourteen mutually exclusive Soil Orders and a large number of Suborders and Great Groups, based on the physical and chemical characteristics of a soil. A brief description of the major Soil Orders follows, in order to give a general impression of the system. The list is intended to be read through in order until the first definition that 'fits' the soil being examined is found. It must be noted that the definitions within the 'grey book' are somewhat more technical and phrased differently, and have been modified here to avoid copyright infringement.

Anthroposols, soils created by human activity,
Organosols, soils not regularly inundated by marine waters and containing a specific thickness of organic materials within the upper part of the profile,
Podosols, other soils containing a Bs, Bhs, or Bh horizon according to the definition in the Australian Soil and Land Survey Field Handbook (the 'yellow book'),
Vertosols, other soils that both contain more than 35% clay throughout the solum and possess deep cracks wider than 5mm during most years and contain slickensides or lenticular peds at some depth within the solum,
Hydrosols, other soils that are largely saturated for at least several months in most years,
Kurosols, other soils with a clear or abrupt textural B horizon and in which the upper part of the B horizon is strongly acid,
Sodosols, other soils similar to kurosols but with the upper part of the B horizon being sodic rather than acidic,
Chromosols, other soils similar to kurosols but without the strongly acidic layer,
Calcarosols, other soils that contain carbonate accumulations throughout the solum, that must have formed in situ,
Ferrosols, other soils with an iron oxide content of greater than 5%,
Dermosols, other soils with B2 horizons more developed than weak,
Kandosols, other soils with well-developed B2 horizons with 'massive' or 'weak' structure as defined in the 'yellow book',
Rudosols, other soils with rudimentary pedological development (little or no B horizon, minimal A horizon development, little colour or texture change with depth),
Tenosols, all other soils.

Suborders and Great Groups are defined further through characteristics such as location within a landform and physical features such as colour, texture, mineral makeup and pH.

This section requires expansion.