Gelisol
As GELISOL is referred to in accordance with the USDA Soil Taxonomy mild to moderately acidic soils of the northern polar regions , which are characterized in that they even in summer from a depth of less than two meters frozen are. You can find them sporadically in the high mountains and in the south polar region.
The prevailing very low temperatures ensure that the decomposition of the organic matter by bacteria and fungi takes place very slowly, which means that dead material accumulates on the surface. The content of organic carbon compounds is therefore very high. In summer, the ice melts in the uppermost soil layer (active layer); the resulting water cannot run off through the still frozen subsoil and thus leads to the formation of swamps .
Near the transition area between liquid and solid water, the fluctuating temperatures during the day lead to an even cycle of thawing and renewed freezing, which literally kneads the soil, a phenomenon known as cryoturbation . On the surface, this cycle leads to a natural sorting of the existing stone material according to size, so that complicated polygonal patterns can form.
Gelisols take up around 11.3 million square kilometers or 8.6 percent of the earth's ice-free land area and cannot be used for arable farming. The typical forms of vegetation are taiga , tundra and bog .
classification
A distinction is made between three gelisol suborders:
Web links
literature
- Soil Survey Staff: Soil Taxonomy: A Basic System of Soil Classification for Making and Interpreting Soil Surveys. 2nd edition. Natural Resources Conservation Service. US Department of Agriculture Handbook 436.Washington DC, USA, 1999.
- Soil Survey Staff: Keys to Soil Taxonomy. 12th edition. Natural Resources Conservation Service. US Department of Agriculture. Washington DC, USA, 2014.
