INI

WRB Reference Soil Groups - INI

The WRB Reference Soil Groups represent the highest hierarchical level in the World Reference Base for Soil Resources (WRB), established by the International Union of Soil Sciences (IUSS). The fourth edition of 2022 defines 32 Reference Soil Groups (RSGs), systematically classified based on soil-forming processes and characteristics. This classification system is widely used as a standard reference for creating soil maps and facilitating international soil information exchange.

soil classification WRB IUSS Reference Soil Groups soil science pedology
[item.histosol]
code=HS
slug=histosol
name=Histosol
description=Soils with thick organic layers.
category=Soils with thick organic layers

[item.anthrosol]
code=AT
slug=anthrosol
name=Anthrosol
description=Soils with long and intensive agricultural use, often altered to enhance fertility.
category=Soils with strong human influence

[item.technosol]
code=TC
slug=technosol
name=Technosol
description=Soils containing significant amounts of artefacts.
category=Soils with strong human influence

[item.cryosol]
code=CR
slug=cryosol
name=Cryosol
description=Permafrost-affected soils.
category=Soils with limitations to root growth

[item.leptosol]
code=LP
slug=leptosol
name=Leptosol
description=Thin soils or soils with many coarse fragments.
category=Soils with limitations to root growth

[item.solonetz]
code=SN
slug=solonetz
name=Solonetz
description=Soils with a clay-enriched subsoil with high concentrations of exchangeable Na.
category=Soils with limitations to root growth

[item.vertisol]
code=VR
slug=vertisol
name=Vertisol
description=Soils with high contents of shrink-swell clays, alternating wet-dry conditions.
category=Soils with limitations to root growth

[item.solonchak]
code=SC
slug=solonchak
name=Solonchak
description=Soils with high concentrations of soluble salts.
category=Soils with limitations to root growth

[item.gleysol]
code=GL
slug=gleysol
name=Gleysol
description=Groundwater-dominated soils, underwater or in tidal areas.
category=Soils distinguished by Fe/Al chemistry

[item.andosol]
code=AN
slug=andosol
name=Andosol
description=Soils with allophanes and/or complexes of Al and organic matter.
category=Soils distinguished by Fe/Al chemistry

[item.podzol]
code=PZ
slug=podzol
name=Podzol
description=Soils with subsoil accumulation of organic matter and/or oxides.
category=Soils distinguished by Fe/Al chemistry

[item.plinthosol]
code=PT
slug=plinthosol
name=Plinthosol
description=Soils with accumulation and redistribution of Fe.
category=Soils distinguished by Fe/Al chemistry

[item.planosol]
code=PL
slug=planosol
name=Planosol
description=Soils with stagnant water and abrupt textural difference.
category=Soils distinguished by Fe/Al chemistry

[item.stagnosol]
code=ST
slug=stagnosol
name=Stagnosol
description=Soils with stagnant water and no or only moderate textural difference.
category=Soils distinguished by Fe/Al chemistry

[item.nitisol]
code=NT
slug=nitisol
name=Nitisol
description=Soils with low-activity clays, P fixation, many Fe oxides, strongly structured.
category=Soils distinguished by Fe/Al chemistry

[item.ferralsol]
code=FR
slug=ferralsol
name=Ferralsol
description=Soils with dominance of kaolinite and oxides.
category=Soils distinguished by Fe/Al chemistry

[item.chernozem]
code=CH
slug=chernozem
name=Chernozem
description=Soils with very dark and well-structured topsoil and secondary carbonates.
category=Pronounced accumulation of organic matter in the mineral topsoil

[item.kastanozem]
code=KS
slug=kastanozem
name=Kastanozem
description=Soils with dark topsoil and secondary carbonates.
category=Pronounced accumulation of organic matter in the mineral topsoil

[item.phaeozem]
code=PH
slug=phaeozem
name=Phaeozem
description=Soils with dark topsoil, no secondary carbonates (unless very deep), and high base status.
category=Pronounced accumulation of organic matter in the mineral topsoil

[item.umbrisol]
code=UM
slug=umbrisol
name=Umbrisol
description=Soils with dark topsoil and low base status.
category=Pronounced accumulation of organic matter in the mineral topsoil

[item.durisol]
code=DU
slug=durisol
name=Durisol
description=Soils with accumulation of, and cementation by, secondary silica.
category=Accumulation of moderately soluble salts or non-saline substances

[item.gypsisol]
code=GY
slug=gypsisol
name=Gypsisol
description=Soils with accumulation of secondary gypsum.
category=Accumulation of moderately soluble salts or non-saline substances

[item.calcisol]
code=CL
slug=calcisol
name=Calcisol
description=Soils with accumulation of secondary carbonates.
category=Accumulation of moderately soluble salts or non-saline substances

[item.retisol]
code=RT
slug=retisol
name=Retisol
description=Soils with interfingering of coarser-textured, lighter-coloured material into a finer-textured, stronger-coloured layer.
category=Soils with clay-enriched subsoil

[item.acrisol]
code=AC
slug=acrisol
name=Acrisol
description=Soils with low-activity clays and exchangeable Al greater than exchangeable base cations.
category=Soils with clay-enriched subsoil

[item.lixisol]
code=LX
slug=lixisol
name=Lixisol
description=Soils with low-activity clays and exchangeable base cations equal to or greater than exchangeable Al.
category=Soils with clay-enriched subsoil

[item.alisol]
code=AL
slug=alisol
name=Alisol
description=Soils with high-activity clays and exchangeable Al greater than exchangeable base cations.
category=Soils with clay-enriched subsoil

[item.luvisol]
code=LV
slug=luvisol
name=Luvisol
description=Soils with high-activity clays and exchangeable base cations equal to or greater than exchangeable Al.
category=Soils with clay-enriched subsoil

[item.cambisol]
code=CM
slug=cambisol
name=Cambisol
description=Moderately developed soils.
category=Soils with little or no profile differentiation

[item.fluvisol]
code=FL
slug=fluvisol
name=Fluvisol
description=Soils with stratified fluviatile, marine or lacustrine sediments.
category=Soils with little or no profile differentiation

[item.arenosol]
code=AR
slug=arenosol
name=Arenosol
description=Very sandy soils.
category=Soils with little or no profile differentiation

[item.regosol]
code=RG
slug=regosol
name=Regosol
description=Soils with no significant profile development.
category=Soils with little or no profile differentiation