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The world needs for food and fiber continue to increase. Population
growth in the developing countries peaked at 2. 4% a year in 1965
and has fallen to about 2. 1%. However, in many developing
countries almost half the people are under 15 years of age, poised
to enter their productive and reproductive years. The challenges to
produce enough food for this growing population will remain great
Even more challenging is growing the food in the areas of greatest
need. Presently the world has great surpluses of food and fiber in
some areas while there are devastating deficiencies in other areas.
Economic conditions and the lack of suitable infrastructure for
distribution all too often limit the alleviation of hunger even
when there are adequate supplies, sometimes even within the country
itself. World hunger can be solved in the long run only by
increasing crop production in the areas where the population is
growing most rapidly. This will require increased efforts of both
the developed and developing countries. Much of the technology that
is so successful for crop production in the developed countries
cannot be utilized directly in the developing countries. Many of
the principles, however, can and must be adapted to the conditions,
both physical and economic, of the developing countries.
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earliest historical references have to do with erosional forces of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."
The steadily increasing cost of nitrogen fertilizer has resulted in
more emphasis on basic and applied studies to improve nitrogen use
efficiency in lowland rice. The efficiency of fertilizer nitrogen
in farmers' fields is shockingly low ~ a luxury resource-scarce
farmers in tropical Asia can ill afford. We believe it is critical
to quantify the basic transformation processes and develop
management practices for higher N use efficiency for two reasons.
They are: 1. Nitrogen fertilizer together with water management is
a key factor for achieving the yield potentials of modern rices. 2.
Fertilizer nitrogen prices are high and most Asian rice farmers are
poor. The International Rice Research Institute (IRRI),
Philippines; Internation al Fertilizer Development Center (IFDC),
USA; Commonwealth Scientific and Industrial Research Organization
(CSIRO), Australia; U.S. Universities (Louisiana, Cornell,
California, Arkansas and others); and Dr Justus Leibig University
in West Germany are actively engaged in individual or collaborative
research that addresses basic transformation processes on N gains
and losses and management practices to maximize N use efficiency in
rice. It is appropriate to update and summarize, in a double issue
of Fertilizer Research, the 10 papers presented at the special
symposium organized by the American Society of Agronomy (ASA) at
the 75th Annual Meeting in Washington, D.C. in 1983. S.K. De Datta,
Head of Agronomy Department, IRRI, was chairman of the
International Agronomy Division of ASA (A-6) in 1982 and 1983.
Forty years ago, when PLANT AND SOIL first appeared, Europe was
still recovering from the devastating effects of World War II.
During the war years, work in many centres of agricultural research
had come to a virtual standstill. Buildings and equipment were
destroyed, scientists were often forced to terminate their research
and teaching activities and funds allocated to such work were
diverted to other, at that time, more pressing needs. During the
first post-war years reconstruction was undertaken with great zeal
and in that light the founding of the new journal PLANT AND SOIL
must be viewed. In the pre-war period most agricultural science
journals were still primarily national ones and consequently many
articles were published in languages mastered by only a limited
number of potential readers. In small countries whose languages are
not widely understood, the desire arose to publish research
findings in one of the major languages. It is therefore
understandable that in the early years of the journal's existence,
large portions of PLANT AND SOIL were filled with articles from the
Scandinavian countries and The Nether lands. Originally, rather
frequent use was made of the opportunity to publish also in German
and French, but with the advance of English as a major language of
communication, a decline was noticeable in the number of German and
French manuscripts submitted. As a consequence the Edi torial Board
has recently decided to terminate the publishing of articles in
these languages."
The International Society ofSoil Science was organized in 1924 and
the 1st International Congress ofthe Society was held in
Washington, D. C. , United States ofAmerica, in 1927. The 14th
Congress was held August 12-18, 1990 in Kyoto, Japan. Dr. Akira
Tanaka, Society President, stated "It is a serious
concernofpeopleintheworldtosustainhighfarming productivityfor
feeding the ever growing population,and also to protect the
environment for human habitation. For this purpose, it is necessary
to maximize crop yield per unit field
areathroughintensivemanagementofthesoilandcropsonlands which are
best suited for crop production, and to leave lands which are
suboptimal for crops under natural conditions insofar as possible.
Soil science is respon- siblefor
planningtheoptimumland-usesystem,for managing soilsand crops with
maximum efficiency, and for fighting intelligently against soil
deteriora- tion. " Dr. Tanaka clearly stated the challenges facing
soil scientists, and they are indeed challenges. Even though the
rate ofworld population growth has decreased somewhat in recent
years, the consensus is that total population willdouble-to some
ten billion-beforeit stabilizes. The increased produc- tion of
food, fiber, and fuelwood necessary for the people will require a
continued supply ofnew technologies and management practices. The
consensus of many scientists is that the greatest challenge is not
increasing production, but preventing serious deterioration of the
soil and waterresource base so theproductionlevel can be sustained.
Therearemany historical examples where civilizations were
successful for extended periods
onlytoseesoildegradationleadtotheircollapse.
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