Hydromorphic features

 

The analysis of the features formed in the profile by oxido-reduction processes, is a very quick and easy method to estimate hydromorphism, which has been generally accepted in the whole world.

Nevertheless, when using these characteristics, one has to be extremely careful since it must be realized that, although effects are unequivocalley related to the cause it never will be equal to verify hydromorphism by precise in situ measurement of humidity and redox-potential during the year, or to deduce it from a simple observation of its morphological imprints in the profile, how precise these observations may be.

 

Types of features

The characteristic morphological features are manifold (gray, bluish or green colors, bleached zones, red, ocre or black linings) but all are basically the result of the reorganization of the Fe and Mn compounds due to changes of humidity.

The features produced by hydromorphism in the soil can be observed in situ in the profile, but micromorphology represents a more accurate method of analysis. As such the field description of nodules and mottles can be completed with terms from the "Handbook of Soil thin Section Description" of Bullock et al. 1985: depletion, crystalline, cryptocrystalline and amorphous pedofeatures (nodules, coatings, hypo-coatings and quasi-coatings).Each of these features, their distribution and mutual relation, allows to deduce interesting conclusions with respect to the hydromorphic processes which were at their origin

 

Accumulation features

Depletion features

Low chroma matrix

 

Eluviation versus illuviation

 

 

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