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Types of Soils of the world

Soils are categorized into 3 types.  They are Group-I , Group-II and Group-III
Group I
Soils with well developed horizons or with fully weathered minerals, resulting from long-continued adjustmet to prevailing soil temperature and soil water conditions.
·         Oxisols:  Very old, highly weathered soils of low latitudes, with a subsurface horizon of accumulation of mineral oxides and very low base status.
·         Ultisols:  Soils of equatorial, ropical, and subtropical latitude zones, with a subsurface hjorizon of clay accumulation and low base status.
·         Vertisols:  Soils of e subtropical and tropical  zones with high clay content and high base status. Vertisols develop deep, wide cracks when dry, and the soil blocks formed by cracking move wih respect to each other.
·         Alfisols:  Soils of humid and subhumid climates with a subsurface horizon of clay accumulation and high base status.  Alfisols range from equatorial to subarctic latitude zones.
·         Spodosols: Soils of cold, moist climates, with a well-developed B horizon of illuviation and low base status.
·         Mollisols:  Soils  of semiarid and subhumid midlatitude grasslands, with a dark, humusd-rich epipedon and very high base status.
·         Aridisols: Soils of dry climates, low in organic matter, and often haivn subsurface horizons of accumulation of carbonate minerals or soluble salts.\

 Group II
Soils with a large proportion of organic matter
·         Histosols:  Soils with a thick upper  layer very rich in organic matter.

 Group III
 Soils with  poorly developed horizons or no horizons, and capable of further mineral alteration.
·         Entisols: Soils lacking horizons, usually because their parent material  has accumulated only recently.
·         Inceptisols: : Soils  with weakly developed horizons, having minerals capable of further  alteration  by weathering processes.
·         Andisols: Soils with weakly developed  horizons, having a high proportion of glassy volcanic parent  material produced by erupting  volcanoes.