Horizon notations and diagnostic characteristics Flashcards
O
Organic material, accumulated under wet conditions
A
Mineral horizon (topsoil) formed at the soil surface characterised by incorporation of humified organic matter
Ah
Topsoil undisturbed by ploughing
Ap
Topsoil disturbed by ploughing
E
Horizon below the H, O, or A horizon that has lost clay, iron or aluminium (eluviated) leaving it relatively pale
A/B
Zone of mixing between A and B horizons, frequently caused by worms
B
A mineral horizon that has been altered by the formation of soil structure, brighter colours (than horizons above or below), or by enrichment in mineral or organic material
Bw
weather B-horizon
B horizon, altered by weathering, evidenced by contrast in colour or structure
Bg
argillic horizon
B horizon enriched in clay
Bh
podzolic B-horizon
Dark B horizon enriched in humus
Bs
podzolic B-horizon
B horizon enriched in oxides of iron, aluminium with humus
Bo
oxidic horizon
B horizon enriched in kaolin-group clays with iron and aluminium oxides
Bg
Mottled profile form, gley profile form, perch-gley features
B horizon with mottled grey and yellow/orange colours indicative of reduction (gleying)
Br
Gley profile form, perch-gley features
B horizon with strong reduction due to intense gleying and predominant grey colours.
Bk
Calcareous horizon
B horizon enriched in calcium carbonate
