A horizon


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Related to A horizon: C horizon, B horizon

A horizon

n.
In ABC soil, the uppermost, darkest zone that is rich in organic matter. Also called zone of eluviation, zone of leaching.

A horizon

n
(Physical Geography) the top layer of a soil profile, usually dark-coloured and containing humus and from which soluble salts may have been leached. See B horizon, C horizon

A horizon


n.
the topsoil in a soil profile.
[1935–40]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.A horizon - the top layer of a soil profileA horizon - the top layer of a soil profile; usually contains humus
humus - partially decomposed organic matter; the organic component of soil