| Luvisol | |
|---|---|
 Luvisol from the Netherlands | |
| Used in | WRB, other |
| WRB code | LV |
| Profile | AhEBtC |
| Climate | Humid temperate climate |
Luvisols are a group of soils, comprising one of the 32 Reference Soil Groups in the international system of soil classification, the World Reference Base for Soil Resources (WRB). [1] They are widespread, especially in temperate climates, and are generally fertile. Luvisols are widely used for agriculture. [2]
Luvisols cover 500–600 million ha of land area, mainly in the temperate zones. They form on a wide variety of mineral parent materials. In Mediterranean regions, the formation of hematite can produce red-coloured Chromic Luvisols. [2]
The main characteristic of Luvisols is an argic horizon, a subsurface zone with higher clay content than the material above it. [1] This typically arises as clay is washed downward by water and accumulates at greater depth. The clay minerals have not been extensively weathered and are therefore of the high-activity, 2:1 type, giving these soils high cation exchange capacities and high base saturation. [1] [2] In uneroded landscapes, a lighter, clay-depleted eluvial horizon occurs above the argic horizon. [2]
The Canadian system of soil classification includes Luvisols. In the USDA Soil Taxonomy, Luvisols are typically classified as Alfisols. [2]
Gelisols are an order in USDA soil taxonomy. They are soils of very cold climates which are defined as containing permafrost within two meters of the soil surface. The word "Gelisol" comes from the Latin gelare meaning "to freeze", a reference to the process of cryoturbation that occurs from the alternating thawing and freezing characteristic of Gelisols.
In USDA soil taxonomy, a Psamment is defined as an Entisol which consists basically of unconsolidated sand deposits, often found in shifting sand dunes but also in areas of very coarse-textured parent material subject to millions of years of weathering. This latter case is characteristic of the Guiana Highlands of northern South America. A Psamment has no distinct soil horizons, and must consist entirely of material of loamy sand or coarser in texture. In the World Reference Base for Soil Resources (WRB), Psamments are known as Arenosols.
The World Reference Base for Soil Resources (WRB) is an international soil classification system for naming soils and creating legends for soil maps. The currently valid version is the fourth edition 2022. It is edited by a working group of the International Union of Soil Sciences (IUSS).
Gypsisols in the World Reference Base for Soil Resources (WRB) are soils with substantial secondary accumulation of gypsum (CaSO4.2H2O). They are found in the driest parts of the arid climate zone. In the USDA soil taxonomy they are classified as Gypsids (USDA Soil Taxonomy), in the Russian soil classification they are called Desert soils (USSR).
An Acrisol is a Reference Soil Group of the World Reference Base for Soil Resources (WRB). It has a clay-rich subsoil and is associated with humid, tropical climates, such as those found in Brazil, and often supports forested areas. In the USDA soil taxonomy, Acrisols correspond to the Humult, Udult and Ustult suborders of the Ultisols and also to Oxisols with a kandic horizon and to some Alfisols. The Acrisols low fertility and toxic amounts of aluminium pose limitations to its agricultural use, favouring in many places its use for silviculture, low intensity pasture and protected areas. Crops that can be successfully cultivated, if climate allows, include tea, rubber tree, oil palm, coffee and sugar cane.
Solonetz is a Reference Soil Group of the World Reference Base for Soil Resources (WRB). They have, within the upper 100 cm of the soil profile, a so-called "natric horizon". There is a subsurface horizon (subsoil), higher in clay content than the upper horizon, that has more than 15% exchangeable sodium. The name is based on the Russian соль. Ukrainian folk word "solontsi" means salty soil. In Ukraine there are many villages that are called Solontsі.
Lixisols are a Reference Soil Group of the World Reference Base for Soil Resources (WRB). They are soils with subsurface accumulation of low activity clays and high base saturation. They develop under intensive tropical weathering conditions and subhumid to semi-arid climate.
A Calcisol in the World Reference Base for Soil Resources (WRB) is a soil with a substantial secondary accumulation of lime. Calcisols are common in calcareous parent materials and widespread in arid and semi-arid environments. Formerly Calcisols were internationally known as Desert soils and Takyrs.
A Cambisol in the World Reference Base for Soil Resources (WRB) is a soil in the beginning of soil formation. The horizon differentiation is weak. This is evident from weak, mostly brownish discolouration and/or structure formation in the soil profile.
In the World Reference Base for Soil Resources (WRB), a Durisol is a soil of arid and semi-arid environments that contains cemented secondary silica (SiO2) in the upper metre of soil, either as concretions (durinodes – duric horizon) or als continuously cemented layer (duripan – hardpan (Australia) – dorbank (South Africa) – petroduric horizon). In the FAO/Unesco Soil Map of the World, the Durisols with petroduric horizon were indicated as duripan phase of other soils, e.g. of Xerosols and Yermosols.
A Regosol in the World Reference Base for Soil Resources (WRB) is very weakly developed mineral soil in unconsolidated materials. Regosols are extensive in eroding lands, in particular in arid and semi-arid areas and in mountain regions. Internationally, Regosols correlate with soil taxa that are marked by incipient soil formation such as Entisols in the USDA soil taxonomy or Rudosols and possibly some Tenosols in the Australian Soil Classification.
A Planosol in the World Reference Base for Soil Resources is a soil with a light-coloured, coarse-textured, surface horizon that shows signs of periodic water stagnation and abruptly overlies a dense, slowly permeable subsoil with significantly more clay than the surface horizon. In the US Soil Classification of 1938 used the name Planosols, whereas its successor, the USDA soil taxonomy, includes most Planosols in the Great Groups Albaqualfs, Albaquults and Argialbolls.
A Stagnosol in the World Reference Base for Soil Resources (WRB) is soil with strong mottling of the soil profile due to redox processes caused by stagnating surface water.
An Alisol is a Reference Soil Group of the World Reference Base for Soil Resources (WRB).
A fluvisol in the World Reference Base for Soil Resources (WRB) is a genetically young soil in alluvial deposits. Apart from river sediments, they also occur in lacustrine and marine deposits. Fluvisols correlate with fluvents and fluvaquents of the USDA soil taxonomy. The good natural fertility of most fluvisols and their attractive dwelling sites on river levees and higher parts in marine landscapes were recognized in prehistoric times.
Kastanozem is one of the 32 Reference Soil Groups of the World Reference Base for Soil Resources (WRB). These soils are brighter than Chernozems, and are related to the Mollisols in the USDA soil taxonomy. They are rich in humus, and originally covered with early maturing native grasslands vegetation, which produces a characteristic brown surface layer in the first meter in depth. They have a relative high level of available calcium ions bound to soil particles and can have a petrocalcic horizon between 25 and 100 cm thick.
Plinthosols are iron-rich soils characterized by the presence of plinthite, petroplinthite or pisoliths.
A nitisol in the World Reference Base for Soil Resources (WRB) is a deep, red, well-drained soil with a clay content of more than 30% and a blocky structure. Nitisols correlate with the kandic alfisols, ultisols and inceptisols of the USDA soil taxonomy.
A Phaeozem in the World Reference Base for Soil Resources (WRB) is a dark soil with a high base status, but without a secondary carbonates within one metre of the soil surface. Phaeozems correlate with the Udolls and Aquolls (Mollisols) of the USDA soil taxonomy.
A Retisol is a Reference Soil Group of the World Reference Base for Soil Resources (WRB). Retisols are characterized by clay migration and an additional specific feature: The clay-poorer and lighter coloured eluvial horizon intercalates netlike into the clay-richer more intensely coloured illuvial horizon. The illuvial horizon is the diagnostic argic horizon, and the intercalation is called retic properties.