Spodosols

Fig. 8-4 Typical soil horizon sequence for a Spodosol developed under a coniferous forest (left) and a Mollisol developed under grasses and herbaceous plants.

Fig. 8-5 Soil and soil forming processes - a global view. The moisture and temperature regimes are generalized and intended only to show major pedoclimatic environments. Spodosols, for example, can also occur in a cryic regime and even in equatorial regions. Other orders could also occur in more than one moisture and temperature environment. (overleaf)...

Soil Order Entisols Gelisols Inceptisols Spodosols Inceptisols Alfisols... 

Plate 3 shows a map of dominant soil orders for the entire world. Although this map necessarily lacks detail due to its scale, the relationship between soils and the biosphere is evident. Different terrestrial ecosystems are correlated with climatic conditions and different soils are correlated with both. For example, Mollisols are common in areas where there are prairies or steppes a result of grasses as the dominant vegetation and low, seasonal rainfall. Spodosols occur where coniferous forests dominate and the climate is cold and wet. Comparing Fig. 8-5 and Plate 3 carefully will show how strong this correlation is for the entire Earth. 

Explain the difference between a Mollisol and a Spodosol. How would cycling of Ca differ in each N ... 

T. R. Fox and N. B. Comerford, Rhizosphere phosphatase activity and phosphatase hydrolyzable organic phosphorus in two forested Spodosols. Soil Biol. Bioehem. 24 579 (1992). 

Figure 2.5. An example of a Spodosol the Kalkaska soil series, the state soil of Michigan (single-grain structure in horizon C means that all the sand particles act independently of each other) [2].

However, groupings of soils can be and are made for all soils on this planet, and all soil types can be found on all continents except Antartica. Ultisols, Mollisols, Alfisols, and Spodosols, and other soil types occur in North and South America, Asia, Europe, and Africa, Australia, and New Zealand. Thus, researchers and analysts all over the world need to know about soils, soil types, and their nomenclature. 

The pH and clay content of these soils are extremely important in understanding their chemistry. The lack of salts, low pH, and dominance of low activity clays will greatly affect the retention and extraction of components from both Ultisols and Spodosols. 

Courchesne F, Turmel MC, Beauchemin P. Magnesium and potassium release by weathering Spodosols grain surface coating effects. J. Soil Sci. Soc. Am. 1996 60 1188-1196. 

Soil In both soils and water, chemical and biological mediated reactions can transform thiram to compounds containing the mercaptan group (Alexander, 1981). Decomposes in soils to carbon disulfide and dimethylamine (Sisler and Cox, 1954 Kaars Sijpesteijn et al., 1977). When a spodosol (pH 3.8) pretreated with thiram was incubated for 24 d at 30 °C and relative humidity of 60 to 90%, dimethylamine formed as the major product. Minor degradative products included nitrite ions (nitration reduction) and dimethylnitrosamine (Ayanaba et al., 1973). 

Soils found primarily in cool and humid forested regions, Spodosols have subsurface accumulations of amorphous materials, mainly iron and aluminum oxides. These soils are usually strongly leached, blit can be used for crop support with addition of lime and fertilizer,... 

Soil orders Alf, alfisol And, andisol Cam, cambisol Gley, gleysol Hist, histosol Inc, inceptisol Moll, mollisol Ox, oxisol Spod, spodosol Ult, ultisol. 

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