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The papers contained in this book were presented at a NATO Advanced
Research Workshop (ARW) held at Cape Sounion, Athens, Greece, 19-24
May, 1991. The twenty-eight more comprehensive papers represent the
key subjects of the ARW covered by invited speakers. The
thirty-four short papers pre sented in a research format are
contributions of those invited to participate in the ARW. There was
a total of 70 participants from 21 countries. The objectives of the
ARW were as follows: to review current knowledge of biological
control of plant diseases and plant parasitic nematodes, with
emphasis on mechanisms at the molecular, cellular, organismal, and
ecosystem level; to examine and expand on current concepts and
synthesize new concepts; to identify and prioritize limitations in
the use of biological control for plant diseases and nematodes and
the scientific research needed to overcome these limitations; and
to develop strategies for biological control through management of
resident agents or introduction of natural or modified agents."
The papers contained in this book were presented at a NATO Advanced
Research Workshop (ARW) held at Cape Sounion, Athens, Greece, 19-24
May, 1991. The twenty-eight more comprehensive papers represent the
key subjects of the ARW covered by invited speakers. The
thirty-four short papers pre sented in a research format are
contributions of those invited to participate in the ARW. There was
a total of 70 participants from 21 countries. The objectives of the
ARW were as follows: to review current knowledge of biological
control of plant diseases and plant parasitic nematodes, with
emphasis on mechanisms at the molecular, cellular, organismal, and
ecosystem level; to examine and expand on current concepts and
synthesize new concepts; to identify and prioritize limitations in
the use of biological control for plant diseases and nematodes and
the scientific research needed to overcome these limitations; and
to develop strategies for biological control through management of
resident agents or introduction of natural or modified agents."
From the beginning of agriculture until about 1950, increased food
production came almost entirely from expanding the cropland base.
Since 1950, however, the yield per unit of land area for major
crops has increased dramatically. Much of the increase in yields
was because of increased inputs of energy. Between 1950 and 1985,
the farm tractor fleet quadrupled, world irrigated area tripled,
and use of fertilizer increased ninefold. Between 1950 and 1985,
the total energy used in world agriculture increased 6. 9 times.
Irrigation played a particularly important role in the rapid
increase in food production between 1950 and 1985. The world's
irrigated land in 1950 totaled 94 million hectares but increased to
140 million by 1960, to 198 million by 1970, and to 271 million
hectares in 1985. However, the current rate of expansion has slowed
to less than 1 % per year. The world population continues to
increase and agricultural production by the year 2000 will have to
be 50 to 60% greater than in 1980 to meet demands. This continued
demand for food and fiber, coupled with the sharp decline in the
growth rate of irrigation development, means that much of the
additional agricultural production in future years must come from
cultivated land that is not irrigated. Agricultural production will
be expanded in the arid and semiarid regions because these regions
make up vast areas in developing countries where populations are
rapidly rising.
Located mainly across Portsea Island on the south coast, the city
of Portsmouth is best known for its maritime heritage and
association with the Royal Navy. Its strategic location presented
obvious importance in wartime, which saw Admiral Lord Nelson
sailing from the harbour to his victory at Trafalgar and his doom.
Today it is still a busy port, but the ships that set sail are for
tourism, business and friendship, not war. In this book, authors R.
J. Cook & K. C. Close provide a fascinating visual chronicle of
how much the city has changed across the last century. Using sepia,
black-and-white and colour photographs they show how the city
expanded and developed across the decades. Readers will glimpse
lost and forgotten scenes from the Victorian and Edwardian eras,
through both world wars and right up to more recent times. In
addition to the streets, buildings and industries, together with
the naval and military connections, the book offers a fascinating
record of the people of the city and their constantly changing way
of life. Lost Portsmouth is an engrossing look back in time that
will appeal to residents, visitors and all those with links to the
city.
The railway route between Oxford and Cambridge – nicknamed the
Varsity Line – was opened in stages in the nineteenth century.
Running roughly east to west, it crossed several major trunk routes
linking London with the North and Midlands, and became part of the
LMS in 1923 Railway Grouping. Its strategic value was recognised
during the Second World War as it allowed freight traffic to avoid
London and several new connections to the line were built. Despite
post-war plans to develop the line further, parts of the line were
closed by BR in the 1960s. Since then, rising demand on the
railways in general and recognition of the value of this through
route have resulted in sections being reopened and a new company,
East West Rail, has been founded to re-establish the entire line by
2030, linking Oxford, Bicester, Bletchley/Milton Keynes, Bedford
and Cambridge, and also acting as a potential feeder route for HS2.
This book surveys the history of this route and its operations, and
looks at the campaign and plans to open it again, analysing both
the benefits and downsides of such a large rail project today.
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