One of the Podzols is on the upper slope and has a dominant E horizon; the other is on the footslope and has a dominant spodic horizon
. Mean air temperature is 6.5[degrees]C, and mean annual precipitation is 1935 mm (Sommer 2002).
The spodic horizon
represents an accumulation of illuviated organic matter and iron and aluminum oxides lying underneath a bleached horizon.
The process was especially intensive (11.6 mg [m.sup.-2] [yr.sup.-1]) per centimetre in the spodic horizon
and only a little slower (10.1 mg [m.sup.-2] [yr.sup.-1] [cm.sup.-1]) in the ochric epipedon.
On the top horizon, under the leaf litter and humus, the acids resulting from organic matter decomposition alter clay intensively and the resulting products accumulate further down, making a spodic horizon
rich in sesquioxides and humic compounds.
If the topsoil is thinned by erosion, the spodic horizon
may be mixed into the topsoil by tillage.
Podzols require a spodic horizon
starting within 200 cm from the surface.
Spodosols, soils that form beneath cool, wet, coniferous forests, have a unique feature called a spodic horizon
in which SOM increases.
Frequently, the Cryorthents show podzolic features (Table 2, D2) without fitting the definition of a spodic horizon
(Beyer et al.
Spodosols have a pronounced spodic horizon
where iron, aluminum, and organic matter have accumulated.
The soil is characterized by a sandy texture and represents a Podzol with well-expressed spodic horizons
of yellow-ocherous tones underlying albic horizons that were affected by the fire.
A previous study reported that the soil development grades from undifferentiated parent material at the Lake Michigan shoreline to soils with well-defined albic and spodic horizons
The mass ratios of OC to iron (OC:Fe) of the extracts in some low pH, organic samples (e.g., spodic horizons
) implied the presence of organo-iron complexes rather than adsorbed forms.