Myths
and
Science
about
the
Chemistry
and Fertility
of Soils
in the
Tropics
Pedro
A. Sanchez
North
Carolina
State University
Raleigh,
North
Carolina
Terry
J. Logan
Ohio State Uriversity
Columbus,
Ohio
In many
scientific
and popular
publications,
soils o! the tropics
are consi- dered to be universally
acid, infertile,
and often incapable
of sustained
agricul-
tural production
(Gourou,
1966; McNeil,
1964; Goodland
& Irwin,
1975; Friedman,
1977; Irion,
1978; Reiss et al., 1980; Jordan,
1985).
The soil science
literature
shows
that universal
tropical
soil infertility
is a myth devoid
of scien- tific validity.
This myth has generated
major
misconceptions
relevant
to cur-
rent global
issues
such as rural poverty,
land degradation,
deforestation,
biodiversity,
and climate
change.
The historical
development
of this misconception
has been recently
lyzed by Richter
and Babbar
(199i)
ana-
who traced
it from the initial
explora- tions in the tropics
in the early 19th century
(Buchanan,
1807),
through
the prevalence
of broad
soil genesis
theories
during
the first half of the 20th cen- tury (Sibirtzev,
1914; Jenny,
1941),
apd finally
to the lack of utilization
of quantitative
data about
the diversity
and management
of soils in the tropics, g,.-._ted
largely
during
the second
half of this century.
Richter
and babbar
cite telli.,.
examples
of how major
ecological
texts still use obsolete
concepts about
soils,
and conclude
that
the myth is a consequence
of a major
com-
munications
gap between
soil scientists
and other environmental
scientists. Newer
books,
products
of multidisciplinary
efforts,
put this misconception
aside (Leith
& Werger,
1989;
Coleman
et al., 1989).
The myth about
universal
soil infertility
in the tropics
is readily
coun- teracted
by two kinds of evidence.
First, the vast diversity
of soils in the tropics (Sanchez
& Buol, 1975; Moormann
& Van Wambeke,
1978; Drosdoff
et al., 1978) which
is now systematized
according
to quantitative
soil taxonomy
(Soil Survey
Staff,
1975),
a world
soil map (FAO,
1971-1979),
and numerous
and
Copyright
© 1992 Soil Science
Society
of America
and American
Society
of Agronomy,
677
S. Segoe Rd., Madison,
WI 53711, USA. Myths and Science of Soils of the Tropics.
SSSA Spe-
cial Publication
no. 29.
35
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