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Use of suffixes in proposed A horizon revision
Author: Bob Graham    Created on: 8/30/2012    MessageID: 1553

The proposal to revise the A horizon definition, currently under consideration, is as follows:
“A horizons: Mineral horizons that have formed at the soil surface or below an O horizon. They exhibit obliteration of all or much of any original rock structure and show one or more of the following:
(1) an accumulation of humified organic matter closely mixed with the mineral fraction and not dominated by properties characteristic of E or B horizons (defined below);
(2) properties resulting from cultivation, pasturing, or similar kinds of disturbance; or
(3) a morphology that is distinct from the underlying B or C horizon, resulting from processes related to the surface.

Condition #1: These horizons are labeled “A” with no suffix

Condition #2: These horizons are labeled “Ap”

Condition #3: “Avv” horizons fall under this category.

Why is it that Condition #1 requires no suffix? Is it the more “pure” A horizon? If each condition is equal in its status as an A horizon shouldn’t they all have appropriate suffixes?



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Use of suffixes in proposed A horizon revision (current)
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