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About 20 years ago the emphasis in soil chemistry research switched
from studies of problems related to scarcities of plant nutrients
to those arising from soil pollutants. The new problems have come
about because of the excessive uses of fertilizers, the inputs from
farm and industrial wastes, the widespread applications of
anthropogenie xenobiotic chemicals, and the deterioration of soil
structure resulting from certain modern agriculture practises. The
International Society of Soil Science (ISSS) recognized these
problems and challenges. A provisional Working Group was set up in
1978 to focus attention on soil colloids with a view to
understanding better the interactions wh ich take place at their
surfaces. It was recognized that these interactions are fundamental
to problems of soil fertility, as weIl as to those of soil
pollution. After the group had received the official support of
ISSS at its 12th International Congress in New Delhi in 1982 it set
as its priority the assembling and evaluation of information,
relevant to the soil and environmental sciences, concerning the
composition and structure of soil colloids. Prior to that aseries
of Position Papers were published in the Bulletin of the
International Society of Soil Science (Vol. 61, 1981) outlining the
state of knowledge about the composition and properties of soil
colloids.
Soil is formed from physical and chemical weathering of rocks -
processes described historically because they involve eons of
time-by glaciation and by wind and water transport of soil
materials, later deposited in deltas and loessial planes. Soil
undergoes further transformations over time and provides a habitat
for biological life and a base for the development of
civilizations. Soil is dynamic -always changing as a result of the
forces of nature and particularly by human influences. The soil has
been studied as long as history has been documented. Numerous
references to soil are found in historical writings such as
Aristotle (384-322 B. c. ), Theophrastus (372-286 B. c. ), Cato the
Elder (234-149 B. C. ) and Varro (116-27 B. c. ). Some of the
earliest historical references have to do with erosional forces of
wind and water. The study of soils today has taken on increased
importance because a rapidly expanding population is placing
demands on the soil never before experienced. This has led to an
increase in land degradation and desertification. Desertifica tion
is largely synonymous with land degradation but in an arid land
context. Deterioration of soil resources is largely human induced.
Poverty, ignorance, and greed are the indirect causes of
desertification. The direct cause is mismanage ment of the land by
practices such as overgrazing, tree removal, improper tillage,
poorly designed and managed water distribution systems, and
overexploitation."
About 20 years ago the emphasis in soil chemistry research switched
from studies of problems related to scarcities of plant nutrients
to those arising from soil pollutants. The new problems have come
about because of the excessive uses of fertilizers, the inputs from
farm and industrial wastes, the widespread applications of
anthropogenie xenobiotic chemicals, and the deterioration of soil
structure resulting from certain modern agriculture practises. The
International Society of Soil Science (ISSS) recognized these
problems and challenges. A provisional Working Group was set up in
1978 to focus attention on soil colloids with a view to
understanding better the interactions wh ich take place at their
surfaces. It was recognized that these interactions are fundamental
to problems of soil fertility, as weIl as to those of soil
pollution. After the group had received the official support of
ISSS at its 12th International Congress in New Delhi in 1982 it set
as its priority the assembling and evaluation of information,
relevant to the soil and environmental sciences, concerning the
composition and structure of soil colloids. Prior to that aseries
of Position Papers were published in the Bulletin of the
International Society of Soil Science (Vol. 61, 1981) outlining the
state of knowledge about the composition and properties of soil
colloids.
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