Soils in their environment - Fundamentals of the Physical Environment - page 428

A

A

E

Zone of
soil formation

Zone of
soil formation

B

B

C

Zone of
weathering

Parent
material

C

Zone of
weathering

Parent
material

R

Parent Rock

Glacial Deposit

Figure 18.1 Soil profiles on (a) residual and (b) transported parent materials.

WEATHERING MORPHOGENESIS

Gases
and H 2 O

Residues
Organisms

ATMOSPHERE
HYDROSPHERE

BIOLOGICAL
ACTIVITY

ORGANIC
MATTER

RESISTANT
RESIDUE

MIGRATION
STRATIFICATION
AGGREGATION
MIXING

Horizons

SOIL
PROFILE

SOLUTION
OXIDATION
HYDRATION
HYDROLYSIS

Rock mineral s Clay minerals

PARENT
MATERIAL

ALTERATION
COMPOUNDS

Sesquioxides

Leaching

GROUND AND
SURFACE WATER

WEATHERING
SOLUTION

Figure 18.2 Flow chart of soil formation (pedogenesis).