Definition of 'paleosol', and 'soil', and comments on 'geosol'

Posted by Donald L. Johnson 07 Oct 1999 11:58:45

Colleagues: Somebody once said "He who shouts loudest gets the attention".
Well, lets hope not. We all have a voice. So, with all due respect,
here's mine.

I suggest that the term 'paleosol' be used ONLY for buried soils, because
this concept is consistent with first usage (Erhart, 1932, 1940), it honors
priority, and most importantly it is most LOGICAL. To formally define
'paleosol' as "soils developed on landscapes of the past", as often has
been done, and as has recently AGAIN been proposed, will guarantee -- I
submit -- permanent and continued confusion. The "landscapes of the past"
definition is what has embroiled the term 'paleosol' in controversy and
confusion in the FIRST place -- even among practioners in the field! Do
not institutionalize and codify the confusion by adopting this conceptually
flawed definition for the Glossary of Paleopedology.

Soils at the present land surface receive modern pedogenic imprints
regardless of their genetic nature, or whether one pronounces them as
relict, exhumed, old, very old, fossil, or whatever. In addition, all
soils (pedons, polypedons, or whatever) have a different genetic history;
they intuitively HAVE to have different histories! Somebody once said that
Entisols "grow up" to be Ultisols, or Oxisols, or whatever. But, Oxisols
can also "grow down", or change (evolve, regress, whatever) to Entisols
when stability is replaced by denudation (by stream capture, baselevel
changes, tectonics, or whatever). Pedogenesis moves in both directions,
progressive and regressive. All soils have experienced changes and have
theoretically imprinted the evolved conditions of all or most elements of
the immediate and ambient environment (and not JUST climate). In other
words, soils evolve due to the constantly changing multitudinous elements
of the endogenous and exogenous environments, pure and simple. From this
perspective, all soils are polygenetic. And if all soils are polygenetic,
then the term "polygenesis" as applied to soils is probably unnecessary,
other than to emphasize the point that all soils ARE polygenetic.

If soil needs to be defined, it is best defined in very general terms, and
one that seems to cover all cases is one that was suggested some years ago:
"soil is material at the surface of planets and similar bodies altered by
biologic, chemical, and/or physical agents". The definition is universal
in scope, and calls attention to the apparent fact that pedogenesis on
planet Earth is unique inasmuch as it is the only one with biologic agents.

Notice that the term "soil" has been used in this discussion thus far, and
in the discussions of all others who have contributed to this ongoing
conceptual and terminological dialog, including those who protest its use,
without much anxiety about what the hell soil is. Yet, it has been argued
that the term "soil" is confusing, that it has varied and ambiguous
meanings, and that in buried contexts it should be replaced with "geosol".
I submit that this is pure nonsense. We all use the terms "soil" and
"buried soil" regularly, and we understand what we mean as those terms are
used in context. This is true with many words, in any language. Many
textbooks contain "soil" in the title without making editors, publishers or
readers the slightest bit nervous. "Buried soil" has been used well over a
hundred years, a use begun by early giants in the field (e.g., McGee,
Powell, and Leverett, among others). How many times has the term soil been
used in this ongoing dialog where you have been confused about its meaning
in context, about what the writer meant?

I do not agree with everything Vance Holliday wrote in his Newsletter note,
but I do agree with most of it. I especially agree with what he said about
"geosol", that it is an unnecessary and superfluous term regardless of the
fact that it has been codified as a basic pedostratigraphic term in the
North American Stratigraphic Code, where it replaced the time-honored
"soil" (a mistake in my opinion). The expressions "buried soil" and
"paleosol" are synonyms, and can replace "geosol" in every case without
loss of understanding.

Thanks for your attention, and thanks, Vance, for initiating this
discussion.

Confucious, or somebody (Aristotle?), said, "know thyself and nothing in
excess" Hmmmm!

Attachment: See also: CELEBRATING 50 YEARS OF GEOGRAPHY AT ILLINOIS--1949-1999!