The Australian Soil Classification

National Committee on Soil and Terrain, R Isbell

• Publisher: CSIRO PUBLISHING
• Year: 2016
• Print ISBN: 9781486304639
• eBook ISBN: 9781486304653
• Edition: 2
• Topic: Biological Sciences
• Subtopic: Environmental Science
• Index: Biological Sciences

The Australian Soil Classification provides a framework for organising knowledge about Australian soils by allocating soils to classes via a key. Since its publication in 1996, this book has been widely adopted and formally endorsed as the official national system. It has provided a means of communication among scientists and land managers and has proven to be of particular value in land resource survey and research programs, environmental studies and education.Classification is a basic requirement of all science and needs to be periodically revised as knowledge increases. This Second Edition of The Australian Soil Classification includes updates from a working group of the National Committee on Soil and Terrain (NCST), especially in regards to new knowledge about acid sulfate soils (sulfidic materials). Modifications include expanding the classification to incorporate different kinds of sulfidic materials, the introduction of subaqueous soils as well as new Vertosol subgroups, new Hydrosol family criteria and the consistent use of the term reticulate. All soil orders except for Ferrosols and Sodosols are affected by the changes.

Appendix 1

Use of codes in recording classification of soil profiles

Confidence level of classification

In a number of instances it will not be possible to fully classify the soil because of a lack of laboratory data. It is desirable to indicate the level of confidence when any attempt at classification is made.

1.All necessary analytical and/or morphological data are available.

2.Analytical data are incomplete but are sufficient to classify the soil with a reasonable degree of confidence, e.g. free iron oxide data may be lacking but it is known that the soil is formed from basalt.

3.No necessary analytical data are available but confidence is fair, based on a knowledge of similar soils in similar environments, e.g. presence of columnar structure is normally a reliable indicator of sodic soils.

4.No necessary analytical data are available and the classifier has little knowledge or experience with this kind of soil, hence the classification is provisional.

Examples of a coded classification of a soil profile

The codes presented in these examples are listed in the following order:

Confidence level; Order; Suborder; Great group; Subgroup; Family criteria 1–5

This ordering is not prescriptive and the manner in which the classification is recorded on field data sheets is an operational matter. However, the national standard soil profile data base design, developed by the Australian Collaborative Land Evaluation Program (ACLEP), specifies that the coding system outlined in this classification is to be used for data exchange.

Example 1

1 CH AA AH AT A F L O T

This would decode as Bleached, Eutrophic, Red Chromosol; thin, slightly gravelly, loamy/clayey, very shallow. (Confidence level 1).

Example 2

If a level within the classification hierarchy is indeterminable from the available information this should be coded as [YY]:

4 KA AA YY BU

Ferric, ?, Red Kandosol (Confidence level 4). where YY is defined as: Class undetermined.

Example 3

If there is no available class this should be coded as [ZZ]:

1 RU AO ZZ AR

Basic, n/a, Arenic Rudosol (Confidence 1evel 1)

where ZZ is defined as: No available class

Example 4

If only a subset of the family criteria has been recorded then this should be coded as follows:

1 TE IN EA AI A – K K –

Acidic, Petroferric, Red-Orthic Tenosol; thin, –, sandy / sandy, –, (Confidence level 1).

where – is defined as: Not recorded

In this example it is important to note that family criteria with a code of ‘K’ is valid for ‘A1 horizon texture’ and ‘B horizon maximum texture’. Recording of all the family criteria is essential. In order to avoid any future confusion or ambiguity, it is essential to record the family criteria in the same order as they are presented in the publication.

Appendix 2

List of codes and equivalent class names¹

AA	RED
AB	BROWN
AC	YELLOW
AD	GREY
AE	BLACK
AF	DYSTROPHIC
AG	MESOTROPHIC
AH	EUTROPHIC
AI	ACIDIC
AJ	ACIDIC-MOTTLED
AK	ANDIC
AL	AERIC
AM	AQUIC
AN	ANTHROPOSOLS
AO	ARENIC
AP	ARGIC
AQ	ARGILLACEOUS
AR	BASIC
AS	BAUXITIC
AT	BLEACHED
AU	BLEACHED-ACIDIC
AV	BLEACHED-FERRIC
AW	BLEACHED-LEPTIC
AX	BLEACHED-MAGNESIC
AY	BLEACHED-MANGANIC
AZ	BLEACHED-MOTTLED
BA	BLEACHED-SODIC
BB	BLEACHED-VERTIC
BC	CALCAREOUS
BD	CALCIC
BE	CHERNIC
BF	CHERNIC-LEPTIC
BG	CHROMOSOLIC
BH	CRUSTY
BI	DENSIC
BJ	DURIC
BK	PEDARIC
BL	ENDOACIDIC
BN	EPISODIC
BP	ENDOHYPERSODIC
BR	EPIHYPERSODIC
BT	EXTRATIDAL
BU	FERRIC
BV	ARENACEOUS
BW	FI...

Table of contents

• Cover
• Title
• Copyright
• Contents
• Acknowledgements
• Preface to the Second Edition
• Introduction
• Key to Soil Orders
• Anthroposols [AN]
• Calcarosols [CA]
• Chromosols [CH]
• Dermosols [DE]
• Ferrosols [FE]
• Hydrosols [HY]
• Kandosols [KA]
• Kurosols [KU]
• Organosols [OR]
• Podosols [PO]
• Rudosols [RU]
• Sodosols [SO]
• Tenosols [TE]
• Vertosols [VE]
• Glossary
• Colour Classes
• References
• Appendix 1. Use of codes in recording classification of soil profiles
• Appendix 2. List of codes and equivalent class names
• Appendix 3. Class names and equivalent codes, and the level at which they occur in the soil orders
• Appendix 4. Analytical requirements for the Australian soil classification
• Appendix 5. Approximate correlations between the Australian and other soil classifications
• Appendix 6. Summary of changes in the Second Edition