Podzol Horizons

Rationale
Soils are the interface between the atmosphere, biosphere, hydrosphere and geosphere, and their chemical composition is affected by all these. By taking several samples along a vertical profile in a dug pit or a trench, one can study the transition between the influence of all the above compartments. Podzols (Fig. 1) are a particular type of soil, where drainage, vegetation and mineral weathering characteristics impart a typical layering, consisting from top to bottom of the O (humus or organic), E (elluvial or bleached), B (illuvial or accumulative), B/C (intermediate between B and C) and C-horizons (weakly altered, unconsolidated parent material). By comparing the regional patterns of composition of the O and C-horizons, one can gain insights into the relative importance of natural versus anthropogenic processes in an area.

Advantages
Gives vertical profiles and 3-D pictures of element composition, from where processes may be deduced.

Drawbacks
Requires specialist to select site, collect samples (Figs. 2-6) and interpret results.
Soil pit digging is strenuous, time consuming, thus expensive!

PODZOL PROFILE (Photo: C. Reimann) Fig. 1: The dug hole reveals a beautiful, typical podzol profile with its colourful horizons.	SAMPLING THE DIFFERENT HORIZONS (Photo: C. Reimann) Fig. 2: The different podzol horizons are sampled sequentially from bottom to top of the soil pit.
STUDY OF THE SOIL PIT (Photo: C. Reimann) Fig. 3: The podzol profile is carefully described, photographed and sampled.	FIELD SHEET (Photo: C. Reimann) Fig. 4: Important details of the podzol horizons are recorded on a special field sheet.
PODZOL PROFILE INVESTIGATION, METHOD A (Photo: C. Reimann) Fig. 5: The gopher technique...	PODZOL PROFILE INVESTIGATION, METHOD B (Photo: C. Reimann) Fig. 6: The ostrich technique...