Types of soil

Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolinite, ). Most pure clay minerals are white or light-coloured, but natural clays show a variety of colours from impurities, such as a reddish or brownish colour from small amounts of iron oxide.

thumb|A lump of peat thumb|Peat stacks in Südmoslesfehn (Oldenburg (district)|district of Oldenburg, Germany) in 2013 thumb|Peat gatherers at Westhay, [[Somerset Levels in 1905]] thumb|Peat extraction in East Frisia, Germany in 1987

thumb|Humus has a characteristic black or dark brown color and is an accumulation of Soil carbon|organic carbon. Besides the three major [[soil horizons of (A) surface/topsoil, (B) subsoil, and (C) substratum, most soils have an organic horizon (O) on the very surface. Hard bedrock (R) is not in a strict sense soil.]]

thumb|250px|A bog in Lauhanvuori National Park, [[Isojoki, Finland]] thumb|250px|Peat bog and peat to dry, L'Isle-aux-Coudres#Geography|L'Isle-aux-Coudres, [[Quebec, Canada, 1976]] thumb|Bog in Antwerp Province, Belgium thumb|Bog in the Seliger Lake area, Tver Oblast, Russia thumb|Peat extraction in East Frisia, Germany thumb|Drone video of Kakerdaja bog in Estonia (September 2021) thumb|A raised bog in [[Ķemeri National Park, Jūrmala, Latvia, formed approximately 10,000 years ago in the postglacial period and now a tourist attraction.]] A bog or bogland is a wetland that accumulates peat as

thumb|Loess in Vicksburg, Mississippi, United States

Chernozem ( ), also called black soil, black earth, dark earth, regur soil or black cotton soil, is a black-colored soil containing a high percentage of humus (4% to 16%) and high percentages of phosphorus and ammonia compounds. Chernozem is very fertile and can produce high agricultural yields with its high moisture-storage capacity. However, prolonged agricultural use of chernozems still require replenishment with fertilizers because they easily can get depleted of nutrients through continuous decrease in humus content. Chernozems are a Reference Soil Group of the World Reference Base for So

thumb|Soil types by clay, silt and sand composition as used by the United States Department of Agriculture

Podzols, also known as podosols, spodosols, or espodossolos, are the typical soils of coniferous or boreal forests and also the typical soils of eucalypt forests and heathlands in southern Australia. In Western Europe, podzols develop on heathland, which is often a construct of human interference through grazing and burning. In some British moorlands with podzolic soils, cambisols are preserved under Bronze Age barrows.

soil type

thumb|Solonchak ground thumbnail|280px|Devil's Golf Course, Death Valley National Park, United States Solonchak (Russian and Ukrainian: Солончак) is a Reference Soil Group of the World Reference Base for Soil Resources (WRB). It is a pale or grey soil type found in arid to subhumid poorly-drained conditions. The word is Russian for "salt marsh", which is in turn from the Russian sol (соль) "salt".

limestone-derived soil type of the Mediterranean region

systematic categorization of soils

type of manmade (anthropogenic) soil found in the Amazon Basin

thumb|Subsoil layer Subsoil is the layer of soil under the topsoil on the surface of the ground. Like topsoil, it is composed of a variable mixture of small particles such as sand, silt and clay, but with a much lower percentage of organic matter and humus. The subsoil is labeled the B Horizon in most soil mapping systems. Because it has less organic matter than topsoil, subsoil soil colour is mainly derived from iron oxides. Iron oxides and clay minerals form due to weathering. Rainfall moves these weathering products downward as solutes and colloids by rainfall. The subsoil is the depth wher

thumb|A variety of mire types in Carbajal Valley, Argentina thumb|right|Avaste Nature Reserve|Avaste Fen, one of the largest fens in Estonia thumb|right|A valley mire creates a level ground surface in otherwise dramatic topography. Upper Bigo Bog, Rwenzori Mountains, [[Uganda.]] A peatland is a type of wetland whose soils consist of organic matter from decaying plants, forming layers of peat. Peatlands arise because of incomplete decomposition of organic matter, usually litter from vegetation, due to water-logging and subsequent anoxia. Peatlands are unusual landforms that derive mostly from b

thumb|304x304px|Distribution of Gleysols A gleysol or gley soil is a hydric soil that unless drained is saturated with groundwater for long enough to develop a characteristic colour pattern. The pattern is essentially made up of reddish, brownish, or yellowish colours at surfaces of soil particles and/or in the upper soil horizons mixed with greyish/blueish colours inside the peds and/or deeper in the soil. Gleysols are also known as Gleyzems, meadow soils, Aqu-suborders of Entisols, Inceptisols and Mollisols (USDA soil taxonomy), or as groundwater soils and hydro-morphic soils.

clay material

right|thumb|300px|Solonetz profile 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" ("natrium" is the Latin term for sodium). A subsurface horizon (subsoil), higher in clay content than the upper horizon, has more than 15% exchangeable sodium. The name is based on the Russian соль (sol, meaning salt). The Ukrainian folk word "solontsi" means salty soil. In Ukraine, many villages are called Solontsi.

Ultisol, commonly known as red clay soil, is one of twelve soil orders in the United States Department of Agriculture soil taxonomy. The word "Ultisol" is derived from "ultimate", because Ultisols were seen as the ultimate product of continuous weathering of minerals in a humid, temperate climate without new soil formation via glaciation. They are defined as mineral soils which contain no calcareous (calcium carbonate containing) material anywhere within the soil, have less than 10% weatherable minerals in the extreme top layer of soil, and have less than 35% base saturation throughout the soi

taxonomic unit

thumb|upright=1.6|Alfisols of the world thumb|upright=1.6|One of the environments in which Alfisols can develop is the Temperate deciduous forest

thumb|Rendzina soil (Castelltallat) thumb|Rendzina soil on the Maastrichtian Chalk in Kozubów Landscape Park, Poland Rendzina (or rendsina) is a soil type recognized in various soil classification systems, including those of Britain and Germany as well as some obsolete systems. They are humus-rich shallow soils that are usually formed from carbonate- or occasionally sulfate-rich parent material. Rendzina soils are often found in karst and mountainous regions.

international standard taxonomic soil classification system endorsed by the International Union of Soil Sciences

thumb|Surface runoff of topsoil from a field in Iowa during a rainstorm

thumb|right|upright=1.35|Paleosols sequence, Tuscany, Italy thumb|Etched section of paleosol from the Atlantic, San Salvador Island, Bahamas, indicating the top of the [[Pleistocene Grotto Beach Formation (limestone)]]

upright=1.6|thumb|Vertisols of the world thumb|A more detailed map of the global distribution of Vertisols

classification of soil types

thumb|Muskeg in Tongass National Forest

upright=1.6|thumb|Mollisols of the world upright=1.6|thumb|Mollisols are generally associated with the steppe biome

thumb|upright=1.6|Oxisols of the world thumb|upright=1.6|Oxisols are generally associated with the equatorial forest biome

Andosols are soils found in volcanic areas formed in volcanic tephra. In some cases Andosols can also be found outside active volcanic areas. Andosols cover an estimated 1–2% of Earth's ice-free land surface. Andosols are a Reference Soil Group of the World Reference Base for Soil Resources (WRB). They are closely related to other types of soils such as Vitrosols, Vitrandosols, Vitrons and Pumice Soils that are used in different soil classification systems. The name comes from Japanese ( 'dark') and ( 'soil'), synonymous with (). In the USDA soil taxonomy (ST), many Andosols belong to the orde

thumb|Calcaric Cambisol (Humic) profile in Des'a forest in Ethiopia 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. thumb|400px|right|Distribution of Cambisols Cambisols are developed in medium and fine-textured materials derived from a wide range of rocks, mostly in alluvial, colluvial and aeolian deposits.

thumb|upright=1.3|Alvar in Estonia near the town of [[Keila]] thumb|Alvar at Kinnekulle, [[Sweden. Most plants are confined to the numerous cracks in the limestone.]]

thumb|Leptosol in Abergele (woreda)|Agbe (Ethiopia) A Leptosol in the World Reference Base for Soil Resources (WRB) is a very shallow soil over continuous rock or a deeper soil that is extremely rich in coarse fragments (gravelly and/or stony). Leptosols cover approximately 1.7 billion hectares of the Earth's surface. They are found from the tropics to the cold polar regions and from sea level to the highest peaks. Leptosols are particularly widespread in mountain areas, notably in Asia, South America, northern Canada and Alaska; and in the Saharan and Arabian deserts. Elsewhere, Leptosols can

Aridisols (or desert soils) are a soil order in USDA soil taxonomy. Aridisols (from the Latin aridus, for "dry", and solum) form in an arid or semi-arid climate. Aridisols dominate the deserts and xeric shrublands, which occupy about one-third of the Earth's land surface. Aridisols have a very low concentration of organic matter, reflecting the paucity of vegetative production on these dry soils. Water deficiency is the central defining characteristic of Aridisols. Also required is sufficient age to exhibit subsoil weathering and development. Limited leaching in aridisols often results in one

thumb|upright=1.6|Histosols of the world

type of glaciomarine clay

Latosols, also known as tropical red earth, are soils found under tropical rainforests which have a relatively high content of iron and aluminium oxides. They are typically classified as oxisols (USDA soil taxonomy) or ferralsols (World Reference Base for Soil Resources). Latosols are tropical soils, but not all soils in the tropics are latosolic. Latosols are red or yellowish-red in colour throughout and they do not have distinct horizons like a podsol. The red colour comes from the iron oxides in the soil. They are deep soils, often extending deep whereas podsols are deep.

thumb|Fluvisol profile along Soil in Kilte Awula'ilo|Agula'e River, [[Ethiopia]] thumb|right|400px|Distribution of Fluvisols 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.

thumb|upright=1.6|Entisols of the world upright=1.6|thumb|Entisols of stabilized sand dunes often fall into the Psamment soil suborder. thumb|upright=1.6|Much of the fertile agricultural soils of the Nile valley in Egypt are Entisols developed on alluvial materials (soil suborders Fluvent and Aquent)

upright=1.6|thumb|Andisols of the world upright=1.6|thumb|Many Andisols develop in the immediate vicinity of volcanoes

thumb|The three types of talik: closed, open and through. A talik is a zone of year-round unfrozen ground located in the middle of a permafrost area. In regions of continuous permafrost, taliks often occur underneath shallow thermokarst lakes and rivers, where the deep water does not freeze in winter and thus the soil underneath does not freeze either. Sometimes closed, open, and through taliks are distinguished. These terms refer to whether the talik is surrounded by permafrost, open at the top (e.g. a thermokarst lake), or open both at the top and above an unfrozen layer beneath the permafro

An Acrisol is a Reference Soil Group of the World Reference Base for Soil Resources (WRB). It has a clay-rich subsoil. It 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. Acrisol's 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

type of soil condition

thumb|Soil profile of a Calcic Kastanozem Kastanozem (also known as "chestnut soil") 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 exchangeable calcium ions and secondary carbonates starting within 70 cm of the mineral soil surface.

Yedoma () is an organic-rich (about 2% carbon by mass) Pleistocene-age permafrost with ice content of 50–90% by volume. Yedoma are abundant in the cold regions of eastern Siberia, such as northern Yakutia, as well as in Alaska and the Yukon. ==Characteristics== thumb|Alas landscape in Megino-Kangalassky District, Yakutia The landscape of yedoma areas is of glacier plains and hills with shallow depressions known as alas. Yedoma usually form in lowlands or stretches of land with rolling hills where ice wedge polygonal networks are present, in stable relief features with accumulation zones of poo

thumb|upright=1.6|Inceptisols of the world thumb|upright=1.6|Some soils in urban environments fall into the Inceptisol order (soil suborder Anthrepts|Anthrept)

An anthrosol (or anthropogenic soil) in the World Reference Base for Soil Resources (WRB) is a type of soil that has been formed or heavily modified due to long-term human activity, such as from irrigation, addition of organic waste or wet-field cultivation used to create paddy fields. alt=a soil profile of terra preta|thumb|400x400px|A soil profile of terra preta, an anthrosol found in the Amazon Basin. Such soils can be formed from any parent soil, and are commonly found in areas where agriculture has been practiced for centuries. Anthrosols can be found worldwide, though they tend to have d

thumb|upright=1.6|Gelisols of the world thumb|upright=1.6|Tundra#arctic|Arctic Tundras are the typical environment for the formation of gelisols thumb|upright=1.6|Other gelisols are observed in Tundra#alpine|Alpine Tundras

thumb|Dry akadama thumb|Wet akadama is a naturally occurring, granular clay-like mineral used as soil for bonsai trees and other container-grown plants. It is surface-mined, immediately sifted and bagged, and supplied in various grades; the deeper-mined grade are somewhat harder and more useful in horticulture than the softer, shallow-mined grades. Akadama may also act as one component of growing medium when combined with other elements such as sand, composted bark, peat, or crushed lava. The color darkens when moist which can help the grower determine when to water a tree.

type of soil formed by sedimentation in estuaries

soil type

thumb|Calcaric Solimovic Regosol (Humic) in Degua Tembien, Ethiopia 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. thumb|400px|Distribution of Regosols The group of Regosols is a taxonomic rest

In soil classification, an Umbrisol is a soil with a dark topsoil and in which organic matter has accumulated within the mineral surface soil—in most cases with low base saturation—to the extent that it significantly affects the behaviour and utilization of the soil. Umbrisols are the counterpart of comparable soils with a high base saturation (Chernozems, Kastanozems and Phaeozems).

thumb|Haplic Planosol profile near Abiy Addi in [[Ethiopia]] thumb|right|400px|Distribution of Planosols thumb|Soil profile of a Eutric Planosol 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, Albaquul

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), most Psamments belong to the Arenosols. However, Psamments of fluviatile, lacustrine or m

thumb|Luvic Phaeozem in Ayninbirkekin|Luqmuts, Ethiopia thumb|Distribution of Phaenozem soils as defined by the [[World Reference Base for Soil Resources classification:

thumb|400px|Distribution of Calcisols 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.

soil

soil type