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not promote mineralization of organic matter. Lastly, the calcium they
contain protects carbonaceous materials. But the utilization of these soils
for intensive farming (irrigation, fertilization, ploughings, etc.) enhances
biological activity and mineralization. Chernozems are under threat of
becoming, over time, ordinary soils, that is, poor in humus!
Table 14.1 concerns the classification of continental soils, restricted to the
closest relatives of Chernozems. The exact equivalents in Soil Taxonomy
are hard to give. We should not forget that the ancestor of Soil Taxonomy,
the first version of the 7th Approximation, was conceived by Guy Smith,
Director of Soil Survey Investigations of the USDA in 1952, that is to
say, at the peak of McCarthyism in USA. This was an epoch in which it
was unimaginable to call the soils of USA by Russian names! Thus, the
Americans knowingly clouded the issue and buried the Kastanozems
and Chernozems within the Mollisols!
Classification
Table 14.1 The soils of continental climates arranged from the north to the
south in the Northern Hemisphere; only the Chernozems (16-4%) and the Kasta-
nozems (4-2%) are really rich in humus.
WRB
Soil Taxonomy
Equivalent old terms
Phaeozem
Alb-oll
Grey Forest soil, Brunizem
Chernozem
Ud-oll and Ust-oll
Tchernoziom
Kastanozem
Xer-oll
Steppe Chestnut soil
Calcaric Cambisol
Xer-oll
Sierozem (Russian)
The block of Chernozem, brought by Dokuchaev to the World Fair,
remained in Paris and was offered to the Sorbonne University. Professor
Gèze broke off a fragment that he carried to the institution where he
taught Geology, the Institut National Agronomique. Broken and cracked
with age, the piece could have ended up in the dustbin. The young
generations, who have lost the sense of beauty, have seen only dirty
coal dust where a relic should be imagined. Very fortunately, a vestigial
residue has been saved. It is today preserved at Orléans, in the stores
of the INRA-INFOSOL unit.
GENERAL CONCLUSIONS
We have put soils back in the more general framework of
evolution of the 'altérites' of geologists, that is to say, in a context where
 
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