Profile Characteristics of Some Loess-Derived Soils and Soil Aeration
1955
Ruhe, R. V. | Prill, R. C. | Riecken, F. F.
Inferences are made in evaluating soil drainage conditions from morphological characteristics of soils, such as mottles and deoxidized zones. These characteristics are not infallible criteria for indicating drainage conditions, and an evaluation of local and regional relationships often is necessary for a proper interpretation. An excellent example of the need for such an evaluation is afforded by a study of weathering zones in Wisconsin loess in southwestern Iowa. A repeated occurrence in regional distribution of two deoxidized zones, the upper one surmounted by an abundantly mottled zone, was observed in the Wisconsin loess. The present positions of these deoxidized zones are moderately well or well drained, indicating that they are not related genetically to the present environment but are relict from a preexisting environment of poorer drainage. Well-drained soils occurring on the modern landscape frequently are mottled in the B and C horizons. This mottling in the profiles is interpreted as an incidental morphological characteristic and not related genetically to the profile development, but inherited from a pre-existing environment of poorer drainage.
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