Geoscience Reference
In-Depth Information
Chapter 6
Classifi cation of Cryosols
6.1
Zonal Soil Classifi cation Systems
From 1900 to 1960, soil classifi cation systems in Russia and the USA were genetic,
i.e., based on presumed soil-forming processes, rather than technical or natural, i.e.,
based on soil properties. For example, in the scheme by Baldwin et al. (
1938
), soils
were subdivided into zonal soils, well-developed soils that were in equilibrium with
the climate and vegetation, intrazonal soils, well-developed soils that were infl u-
enced by some local factor such as drainage or parent material, and azonal soils,
those which lacked development because they were young or lacked “pedogenic
inertia” (Bryan and Teakle
1949
). Baldwin et al. (
1938
) recognized zonal soils in
the cold zone that included Tundra soils and Subarctic Brown Forest soils and intra-
zonal soils that included Alpine meadow soils.
Zonal systems were also employed in the polar regions by Tedrow (
1968
,
1977
,
1991
), in the arctic by Ugolini (
1986
), and in the Antarctic by Campbell and
Claridge (
1969
) and Bockheim and Ugolini (
1990
). Tedrow (
1968
) prepared a sche-
matic arrangement of major genetic soils in the polar regions (Table
6.1
). The soils
were arrayed along a hypothetical moisture gradient from the arctic tundra to the
High Arctic and then to the Cold Desert of Antarctica. The Arctic Brown was the
zonal soil in arctic tundra in the region of continuous permafrost; the Polar Desert
soil dominated poorly vegetated High Arctic landscapes underlain by continuous
permafrost; and the Cold Desert soil was the major soil in ice-free areas of Antarctica.
In Antarctica Campbell and Claridge (
1969
) described the zonal soils of Antarctica
as frigic soils (Table
6.2
). Frigic soils were divided according to the available mois-
ture status, which strongly infl uenced soil development: ultraxerous/weakly devel-
oped, xerous/moderately developed, and subxerous/strongly developed. Later
studies showed that the most strongly developed soils were Miocene-aged soils
along the edge of the polar plateau, and subxerous soils along the coast were poorly
developed because they were of Late Glacial Maximum age and younger and were
strongly cryoturbated.
