dr-shorthair
commented
4 years ago Since soils are being discussed again #895 #894 perhaps this one could get a kick along. Here's the key information about the 'orders' in the Australian Soil Classification:
| Name | code | definition |
|---|---|---|
| Anthroposols | AN | Soils resulting from human activities which have led to a profound modification, truncation or burial of the original soil horizons, or the creation of new soil parent materials by a variety of mechanical means. Where burial of a pre-existing soil is involved, the anthropic materials must be 0.3 m or more thick. Pedogenic features may be the result of in situ processes (usually the minimal development of an A1 horizon, sometimes the stronger development of typical soil horizons) or the result of pedogenic processes prior to modification or placement (ie. the presence of identifiable pre-existing soil material). |
| Calcarosols | CA | Soils that are calcareous throughout the solum - or calcareous at least directly below the A1 or Ap horizon, or a depth of 0.2 m (whichever is shallower). Carbonate accumulations must be judged to be pedogenic1 (either current or relict), and the soils do not have clear or abrupt textural B horizons. Hydrosols, Organosols and Vertosols are excluded. |
| Chromosols | CH | Soils other than Hydrosols with a clear or abrupt textural B horizon and in which the major part of the upper 0.2 m of the B2 horizon (or the major part of the entire B2 horizon if it is less than 0.2 m thick) is not sodic and not strongly acid. Soils with strongly subplastic upper B2 horizons are also included even if they are sodic. |
| Dermosols | DE | Soils other than Vertosols, Hydrosols, Calcarosols and Ferrosols which: (i) Have B2 horizons with structure more developed than weak1 throughout the major part of the horizon, and (ii) Do not have clear or abrupt textural B horizons. |
| Ferrosols | FE | Soils other than Vertosols, Hydrosols, and Calcarosols that: (i) Have B2 horizons in which the major part has a free iron oxide free iron oxide1 content greater than 5% Fe in the fine earth fraction (<2 mm), and (ii) Do not have clear or abrupt textural B horizons or a B2 horizon in which at least 0.3m has vertic properties. |
| Hydrosols | HY | Soils other than Organosols, Podosols and Vertosols in which the greater part of the profile is saturated for at least 2-3 months in most years. |
| Kandosols | KA | Soils other than Hydrosols which have all of the following: (i) B2 horizons in which the major part is massive or has only a weak grade of structure. (ii) A maximum clay content in some part of the B2 horizon which exceeds 15% (ie. heavy sandy loam, SL+). (iii) Do not have a tenic B horizon. (iv) Do not have clear or abrupt textural B horizons. (v) Are not calcareous throughout the solum, or below the A1 or Ap horizon or to a depth of 0.2m if the A1 horizon is only weakly developed. |
| Kurosols | KU | Soils other than Hydrosols with a clear or abrupt textural B horizon and in which the major part of the upper 0.2 m of the B2 horizon (or the major part of the entire B2 horizon if it is less than 0.2 m thick) is strongly acid. |
| Organosols | OR | Soils that are not regularly inundated by saline tidal waters and either: (i) Have more than 0.4 m of organic materials within the upper 0.8 m. The required thickness may either extend down from the surface or be taken cumulatively within the upper 0.8 m. or (ii) Have organic materials extending from the surface to a minimum depth of 0.1 m; these either directly overlie rock or other hard layers, partially weathered or decomposed rock or saprolite, or overlie fragmental material such as gravel, cobbles or stones in which the interstices are filled or partially filled with organic material. In some soils there may be layers of humose and/or melacic horizon material underlying the organic materials and overlying the substrate. |
| Podosols | PO | Soils which possess either a Bs horizon (visible dominance of iron compounds), a Bhs horizon (organic-aluminium and iron compounds), or a Bh horizon (organic-aluminium compounds). These horizons may occur singly in a profile or in combination (see Podosol diagnostic horizons). |
| Rudosols | RU | This order is designed to accommodate soils that have negligible pedologic organisation. They are usually young soils in the sense that soil forming factors have had little time to pedologically modify parent rocks or sediments. The component soils can obviously vary widely in terms of texture and depth; many are stratified and some are highly saline. Data on some of them are very limited. By definition, these soils will grade to Tenosols, so before deciding on the order check the Tenosol definition as it will often be a matter of judgement as to which order a particular soil is best placed. Hydrosols are excluded on the basis that these will normally show some pedological development eg. mottling. A particular problem with the definition and subdivision of Rudosols is the difficulty in distinguishing between soil and 'non-soil', (see also 'What do we classify?'). In many instances they are classified on the basis of the nature of AC or C horizon materials or other substrates because these are the dominating features of the profile. It also follows that there may be difficulties in deciding if a soil is best classified as an Anthroposol or be regarded as an ‘anthropic’ Rudosol because the little-altered soil parent material may be human-made. |
| Sodosols | SO | Soils with a clear or abrupt textural B horizon and in which the major part of the upper 0.2 m of the B2 horizon (or the major part of the entire B2 horizon if it is less than 0.2m thick) is sodic and not strongly acid. Hydrosols and soils with strongly subplastic upper B2 horizons are excluded. |
| Tenosols | TE | Soils that do not fit the requirements of any other soil orders and generally with one or more of the following: (i) A peaty horizon. (ii) A humose, melacic or melanic horizon, or conspicuously bleached A2 horizon, which overlies a calcrete pan, hard unweathered rock or other hard materials; or partially weathered or decomposed rock or saprolite, or unconsolidated mineral materials. (iii) A horizons which meet all the conditions for a peaty, humose, melacic or melanic horizon except the depth requirement, and directly overlie a calcrete pan, hard unweathered rock or other hard materials; or partially weathered or decomposed rock or saprolite, or unconsolidated mineral materials. (iv) A1 horizons which have more than a weak development of structure and directly overlie a calcrete pan, hard unweathered rock or other hard materials; or partially weathered or decomposed rock or saprolite, or unconsolidated mineral materials. (v) An A2 horizon which overlies a calcrete pan, hard unweathered rock or other hard materials; or partially weathered or decomposed rock or saprolite, or unconsolidated mineral materials. (vi) Either a tenic B horizon, or a B2 horizon with 15% clay (SL) or less1 , or a transitional horizon (C/B) occurring in fissures in the parent rock or saprolite which contains between 10 and 50% of B horizon material (including pedogenic carbonate). (vii) A ferric or bauxitic horizon >0.2 m thick. (viii) A calcareous horizon >0.2 m thick.with one or more of the following |
| Vertosols | VE | Soils with the following: (i) A clay field texture or 35% or more clay throughout the solum except for thin, surface crusty horizons 0.03 m or less thick and. (ii) When dry, open cracks occur at some time in most years1. These are at least 5 mm wide and extend upward to the surface or to the base of any plough layer, peaty horizon, self-mulching horizon, or thin, surface crusty horizon; and (iii) Slickensides and/or lenticular peds occur at some depth in the solum. See Comment. |
kaiiam
cmungall
wdduncan
New issue to follow up topic raised in https://github.com/EnvironmentOntology/envo/issues/333#issuecomment-370286803
The Australian Soil Classification [1] has the following top-level orders:
AN Anthroposols CA Calcarosols CH Chromosols DE Dermosols FE Ferrosols HY Hydrosols KA Kandosols KU Kurosols OR Organosols PO Podosols RU Rudosols SO Sodosols TE Tenosols VE Vertosols
A turtle file containing the definitions from [1] expressed as skos:Concepts is provided [2], which includes a license from CSIRO Publishing.
[1] http://www.publish.csiro.au/book/7428
[2] ASC-orders.ttl.txt