Geoscience Reference
In-Depth Information
Table 4.12
Specific characteristics diagnostic for organic soils.
Characteristic
Abbreviation Simplified definition
Fibres
Organic fibres more than 2 cm in length
Fibric soil materials
fibr
(L.
fibra =
fibre), undecomposed fibres in large
proportion
Hemic soil materials
hem
Moderately decomposed fibres
Sapric soil materials
sapr
(Gr.
sapros =
rotten), very few fibres, highly
decomposed material, dark-coloured
Humilluvic material
Illuvial organic material accumulated at the
bottom of certain acid soils
Limnic materials
Material deposited in water and found in
certain Histosols except in those of very cold
climates (Histels): faecal pellets, diatoms, marly
deposits
Table 4.13
Characteristics diagnostic for both organic soils and mineral
soils.
Characteristic
Abbreviation Simplified definition
Aquic conditions
(L.
aqua =
water), the periodic or continual
saturation with water is studied by:
We distinguish:
- monitoring the soil water,
- Endosaturation (to
Endo
- colour,
more than 200 cm)
- measurement of redox potential,
-- Episaturation.:
Epi
- presence of concretions and local absence
(e.g.:
perched water
of iron
table)
(
IMPORTANT PROPERTY OFTEN CONSIDERED
)
-- Anthric saturation
related to irrigation
Cryoturbation
(Gr.
kryos =
cold), reorganization of soil consti-
tuents under the influence of frost: undulation of
horizons, oriented coarse fragments, silt caps…
Densic contact
Contact between soil and
densic
material
(see below)
Densic material
Dense material not penetrated by roots and not
actually a rock, e.g. mudflows, till, mine spoils
Gelic material
(Gr.
gelid =
very cold), mineral material show-
ing evidence of cryoturbation
Glacic layer
Ice within the soil, often in lenses
Table 4.13 Contd...
