REGOSOLS

1. REGOSOLS Dr. Selim KAPUR University of Çukurova Departments of Soil Science and Archaeometry Adana, TURKEY kapur@cu.edu.tr

2. DESCRIPTION • From greek rhegos: blanket meaning YOUNG soils on weathering materials • Weakly developed very shallow mineral soils. • Unconsolidated materials • AC profile, MINIMAL PROFILE DEVELOPMENT • Rarely slight lime and/or gypsum accumulation • Slow soil formation due to dry climate • No diagnostic horizons other than an ‘Ochric’ • Extensive on eroded lands ie. in mountain regions • Occurs at all climates but particularly common in arid and semi-arid zones • Correlate with soil taxa marked by incipient soil formation: ‘Entisols’ • Varying management, COMMON USE AS LOW VOLUME GRAZING, BUT BEST FOR FORESTS

3. Gelic Leptic Hyposalic Gleyic Thaptovitric Thaptoandic Arenic Aric Garbic Hyperochric Anthropic Aridic Reductic Spolic Urbic Tephric Gelistagnic Stagnic Humic Gypsiric Calcaric Takyric Yermic Common soil units:

4. No pedological evidence ie color, structure, texture throughout the profile Marine sediment Alluvial material http://www.ucalgary.ca http://www.ucalgary.ca/

5. Arenic Regosol

6. Lacustrine/Wetland sediment

7. Soils of the western coast of Sorkappland Gelic Dystric Regosol (Kulmstranda) Geli-Hyperskeletic Regosol (Gasbreen - frontal moraine) Gelic Dystric Regosol - profile (Kulmstranda)

8. DISTRIBUTION

9. ASSOCIATIONS WITH OTHER SOIL GROUPS • Cryosols in cold regions • Andosols, Leptosols or Umbrisols in mountain regions • Calcisols or Gypsisols in arid regions • Arenosols and Podzols on sandy deposits • Cambisols in semi-arid regions Regosols are integrates with

10. CHARACTERESTICS • The great variation among Regosols (taxonomic rest group!) makes it virtually impossible to give a generalised account of Regosol characteristics. • The central concept of a Regosol is a deep, well-drained, medium-textured, non-differentiated mineral soil that has minimal expression of diagnostic horizons (other than an ochric surface horizon), properties or materials. • Parent material and climate dominate the morphology of Regosols. The content of weatherable minerals varies from low to extremely high (little transformation). • In cool climates, the surface horizon contains poorly decomposed organic matter whereas (ochric) surface horizons tend to be thin, low in organic matter and generally weakly expressed in hot, dry climates. • Regosols in dry regions have generally a higher base status than Regosols in more humid (mountain) regions. • Low coherence of the matrix material makes most Regosols in sloping areas prone to erosion. • Low water holding capacity and high permeability to water make most Regosols sensitive to drought. • Many Regosols in colluvial material are prone to slaking in particular those in löss. This makes them sensitive to erosion in wet periods. Many Regosols form a hard surface crust early in the dry season; the crust hinders emergence of seedlings and infiltration of rain and irrigation water in the dry season.

11. MANAGEMENT AND LANDUSE • Many Regosols are used for extensive grazing • Some on colluvial deposits on loess in N. Europe are used for small grains, sugar beet or fruit trees • In mountain regions best left to forests • In steppe regions with 500-1000 mm ppt needs irrigation with frequent application of water, Sprinkler or trickle suitable for this low water holding capacity but not economical • So better practice DRY FARMING which may be better than installation of costly irrigation facilities