planosol

planosol
planosol [plā′nə säl΄, plā′nəsôl΄]
n.
/span> PLANO- + L solum,SOIL1
[often P-] any of an intrazonal group of soils underlain by B-horizons strongly compacted by material leached from surface horizons, developed on nearly flat uplands

* * *

▪ FAO soil group
 one of the 30 soil groups in the classification system of the Food and Agriculture Organization (FAO) (soil). Planosols are characterized by a subsurface layer of clay (clay mineral) accumulation. They occur typically in wet low-lying areas that can support either grass or open forest vegetation. They are poor in plant nutrients, however, and their clay content leads to both seasonal waterlogging and drought stress. Under careful management they can be cultivated for rice, wheat, or sugar beets, but their principal use is for grazing. Occupying about 1 percent of the total continental land area on Earth, they are found mainly in Brazil, northern Argentina, South Africa, eastern Australia, and Tasmania.

      The characteristic clay-rich layer of Planosols can form from a downward translocation (migration) of clay particles under the action of percolating water, from burial of a clay-rich layer by over-washed coarse material, or from seasonal destruction and translocation of clay (a process known as ferrolysis). The clay layer thus may lie under an extensively leached (and hence nutrient-poor) layer. Planosols are related to the Alfisols (Alfisol) and Ultisols (Ultisol) of the U.S. Soil Taxonomy. Related FAO soil groups also exhibiting clay migration are Luvisols (Luvisol) and Albeluvisols (Albeluvisol).

* * *


Universalium. 2010.

Игры ⚽ Поможем написать реферат

Look at other dictionaries:

  • planosol — ● planosol nom masculin Sol des régions tropicales à forts contrastes saisonniers, développé sur une roche mère plutôt argileuse et dont le profil à horizon superficiel blanchi est très appauvri en argile et en fer …   Encyclopédie Universelle

  • planosol — [plā′nə säl΄, plā′nəsôl΄] n. [< PLANO + L solum,SOIL1] [often P ] any of an intrazonal group of soils underlain by B horizons strongly compacted by material leached from surface horizons, developed on nearly flat uplands …   English World dictionary

  • planosol — plan·o·sol …   English syllables

  • planosol — ˈplanəˌsȯl noun ( s) Etymology: plan (II) + Latin solum ground, soil more at soil : an intrazonal group of soils with strongly leached upper layer over a compacted clay or silt that is developed on smooth flat uplands in cool to warm humid to… …   Useful english dictionary

  • Referentiel pedologique francais — Référentiel pédologique français Le référentiel pédologique français est un ouvrage réalisé par l Association Française pour l Étude du Sol et l INRA. Sommaire : Haut A B C D E F G H I J K L M N O P Q R S T U V W X Y Z …   Wikipédia en Français

  • Référentiel pédologique français — Le référentiel pédologique français est un ouvrage réalisé par l Association française pour l étude du sol et l INRA. Sommaire : Haut A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A …   Wikipédia en Français

  • Colotlán — Municipio de México SanLuisColotlan.jpg …   Wikipedia Español

  • San José de Gracia (Jalisco) — Saltar a navegación, búsqueda Municipio de Tepatitlán de Morelos Escudo …   Wikipedia Español

  • Tlaquepaque — Este artículo o sección necesita referencias que aparezcan en una publicación acreditada, como revistas especializadas, monografías, prensa diaria o páginas de Internet fidedignas. Puedes añadirlas así o avisar al autor p …   Wikipedia Español

  • World Reference Base — Die World Reference Base for Soil Resources (Abkürzung WRB) ist eine Bodenklassifikation, die als internationales Kommunikationsmittel für den Fachbereich Boden geschaffen wurde. Sie ist mehr oder weniger weltweit gültig, um Informationen über… …   Deutsch Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”