In USDA soil taxonomy, a Psamment is defined as an Entisol which consists basically of unconsolidated sand deposits,[1] 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 marine origin belong to the Fluvisols.
Psamments cover 3.4% of the global land mass. They occur throughout the world, being especially abundant in the deserts of Africa and Australia and on the ancient landforms of eastern South America. Areas dominated by Psamments also occur in other humid regions, notably in Florida and Nebraska (the Sand Hills).
Psamments typically have very low water-holding capacities because the sand in the soil is not graded so that sands of varying coarseness are constantly mixed right through the soil. Because most sands are highly siliceous, Psamments are also extremely low in all essential nutrients, most especially phosphorus and are highly acidic in all except very arid climates. Psamments formed as a result of glacial erosion (common in northern Europe) are typically of rather higher native fertility because of their youth, but are still much less fertile than most soils in the regions they are located in.
The vegetation on Psamments varies enormously owing to the variety of climates, but in many cases is remarkably well-adapted to the climate, as with the Fynbos of the Cape region in South Africa—famous for its remarkable biodiversity and the equally species-rich Kwongan of southwestern Western Australia. The campinas and kerangas are healthy forests typical of Psamments in South America and Borneo.
Few Psamments are farmed, and where they are, the cost is high because of the expense of fertilization. They are always much less productive than other soils in the same region even when fertilized, and require careful management because the sand is very easily eroded.
In USDA soil taxonomy, Psamments are divided into:
Cryopsamments: Psamments that have a cryic soil temperature regime
Quartzipsamments: other Psamments that have, in the 0.02 to 2.0 mm fraction within the particle-size control section, a total of more than 90 percent (by weighted average) resistant minerals
Torripsamments: other Psamments that have an aridic (or torric) moisture regime
Ustipsamments: other Psamments that have an ustic moisture regime
Xeropsamments: other Psamments that have a xeric moisture regime
^Unit 10: Terms (Psamment) 2009-04-10 at the Wayback Machine at pals.iastate.edu
Soil Survey Staff: Keys to Soil Taxonomy. 12th edition. Natural Resources Conservation Service. U.S. Department of Agriculture. Washington D.C., USA, 2014.
IUSS Working Group WRB: World Reference Base for Soil Resources, fourth edition. International Union of Soil Sciences, Vienna 2022. ISBN979-8-9862451-1-9 ([1]).
Further readingedit
W. Zech, P. Schad, G. Hintermaier-Erhard: Soils of the World. Springer, Berlin 2022, Chapter 8.3.1. ISBN978-3-540-30460-9
External linksedit
profile photos (with classification) WRB homepage
profile photos (with classification) IUSS World of Soils
January 01, 1970
psamment, usda, soil, taxonomy, defined, entisol, which, consists, basically, unconsolidated, sand, deposits, often, found, shifting, sand, dunes, also, areas, very, coarse, textured, parent, material, subject, millions, years, weathering, this, latter, case, . In USDA soil taxonomy a Psamment is defined as an Entisol which consists basically of unconsolidated sand deposits 1 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 marine origin belong to the Fluvisols Psamments cover 3 4 of the global land mass They occur throughout the world being especially abundant in the deserts of Africa and Australia and on the ancient landforms of eastern South America Areas dominated by Psamments also occur in other humid regions notably in Florida and Nebraska the Sand Hills Psamments typically have very low water holding capacities because the sand in the soil is not graded so that sands of varying coarseness are constantly mixed right through the soil Because most sands are highly siliceous Psamments are also extremely low in all essential nutrients most especially phosphorus and are highly acidic in all except very arid climates Psamments formed as a result of glacial erosion common in northern Europe are typically of rather higher native fertility because of their youth but are still much less fertile than most soils in the regions they are located in The vegetation on Psamments varies enormously owing to the variety of climates but in many cases is remarkably well adapted to the climate as with the Fynbos of the Cape region in South Africa famous for its remarkable biodiversity and the equally species rich Kwongan of southwestern Western Australia The campinas and kerangas are healthy forests typical of Psamments in South America and Borneo Few Psamments are farmed and where they are the cost is high because of the expense of fertilization They are always much less productive than other soils in the same region even when fertilized and require careful management because the sand is very easily eroded In USDA soil taxonomy Psamments are divided into Cryopsamments Psamments that have a cryic soil temperature regime Quartzipsamments other Psamments that have in the 0 02 to 2 0 mm fraction within the particle size control section a total of more than 90 percent by weighted average resistant minerals Torripsamments other Psamments that have an aridic or torric moisture regime Ustipsamments other Psamments that have an ustic moisture regime Xeropsamments other Psamments that have a xeric moisture regime Udipsamments other Psamments Contents 1 See also 2 References 3 Further reading 4 External linksSee also editPedogenesis Pedology soil study Psammosere Soil classification Soil typesReferences edit Unit 10 Terms Psamment Archived 2009 04 10 at the Wayback Machine at pals iastate edu Soil Survey Staff Keys to Soil Taxonomy 12th edition Natural Resources Conservation Service U S Department of Agriculture Washington D C USA 2014 IUSS Working Group WRB World Reference Base for Soil Resources fourth edition International Union of Soil Sciences Vienna 2022 ISBN 979 8 9862451 1 9 1 Further reading editW Zech P Schad G Hintermaier Erhard Soils of the World Springer Berlin 2022 Chapter 8 3 1 ISBN 978 3 540 30460 9External links editprofile photos with classification WRB homepage profile photos with classification IUSS World of Soils Retrieved from https en wikipedia org w index php title Psamment amp oldid 1170566175, wikipedia, wiki, book, books, library,
