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Файл:Scientific English. Учебно-методическое пособие для подготовки аспирантов к сдаче кандидатского минимума по иностранному языку
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It is particularly important that we should not be invaded and taken over by
the same feelings as him. When he cried as a baby, you could just hold and soothe
him.
But, more subtly, it is the home setting - the environment that we provide
for him - that will make him feel safe. Our ability to make rules, to stick to them, to
have a sense of what is appropriate, will contribute to how much he feels that he
can venture forth from a secure base.
The key is to be strong and flexible. This helps to give teenagers confidence.
Parents have to accommodate new aspects of their child, to readjust their picture
of who he is (2135).
Text 23
Work, work, work!
Stress, sleeplessness, depression, heart disease, shortness of temper,
memory loss, anxiety, marital breakdown, child delinquency, the decline of local
neighborhoods, RSI, rudeness, suicide, - a mere shortlist of some of the
symptoms of the postmodern malaise. The cause of all our woes? Enter, stage
right, the prime suspect - work. Wicked, wicked work. An avalanche of surveys,
polls and expert commentaries show that we all work too long, too hard; that our
bosses are beastly; that we are insecure and afraid. You know all this stuff. We
seem to be workers on the verge of a nervous breakdown. So far, so bad. But
there's plenty of good news about work, too - even if it is not always shared with
the same enthusiasm as the 'Work is Terrible' stories. Four out of ten workers
declare themselves ‗very satisfied' with their jobs, more than in France,
Germany, Italy or Spain. Work has become our national obsession.
Women celebrate the economic independence work brings, and then are
made to feel guilty about their children. Salaries go up, but few of us feel richer.
We get to a point where we feel OK about our work; and then along comes
Martha Lane Fox and we think we've missed the life boat. We find a job we love
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and so work long hours at it, and then feel that we are failing to get our
'work/life' balance right.
Why is work under the microscope? Perhaps because our work simply
occupies a more important place in our lives than it did. Maybe we care, and
worry, more about work for the same reason we care and worry so much about
our children or our health - because it is important to us.
But the new salience of work has come with a price; fewer people are able
to feel secure. This would not matter so much if work did not matter so much.
Not just in terms of income, but in terms of identity. When work becomes more
than simply a passport to a pay cheque, when it opens the door to friends,
purpose, satisfaction and a place in the world, its absence is more keenly felt
(2000).
Text 24
Geomorphology
Geomorphology is defined as the science of landforms with an emphasis
on their origin, evolution, form, and distribution across the physical landscape. An
understanding of geomorphology and its processes is therefore essential to the
understanding of physical geography.
Although the study of geomorphology has been around since ancient
times, the first official geomorphologic model was proposed between 1884 and
1899 by the American geographer, William Morris Davis. His geomorphic cycle
model was inspired by theories of uniformitarianism and attempted to theorize the
development of various landform features.
Davis's geomorphic cycle model says that a landscape undergoes a
preliminary uplift that is paired with erosion (the removal or wearing down) of
materials in that uplifted landscape. Within the same landscape, precipitation
causes streams to flow more rapidly. As they grow their power then cuts into the
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ground's surface both at the start of the stream and lower down the stream. This
creates the stream channels present in many landscapes.
This model also says that the slope angle of the land is gradually reduced
and the ridges and divides present in certain landscapes become rounded over time
because of erosion. The cause of this erosion is not however limited to water as in
the stream example. Finally, according to Davis's model, over time such erosion
occurs in cycles and a landscape eventually morphs into an old erosional surface.
Davis's theory was important in launching the field of geomorphology and
was innovative at its time as it was a new attempt to explain physical landform
features. Today however, it is not usually used as a model because the processes he
described are not so systematic in the real world and it failed to take into account
the processes being observed in later geomorphic studies.
Since Davis's model, several alternative attempts have been made to
explain landform processes. Walther Penck, an Austrian geographer, developed a
model in the 1920s for example, that looked at ratios of uplift and erosion. It did
not take hold though because it could not explain all landform features (2150).
Text 25
Geomorphologic Processes
Today, the study of geomorphology is broken down into the study of
various geomorphologic processes. Most of these processes are considered to be
interconnected and are easily observed and measured with modern technology. In
addition, the individual processes are considered to be either erosional,
depositional, or both. An erosional process involves the wearing down of the
earth‘s surface by wind, water, and/or ice. A depositional process is the laying
down of material that has been eroded by wind, water, and/or ice.
The geomorphologic processes are as follows:
Fluvial geomorphologic processes are those related to rivers and streams.
The flowing water found here is important in shaping the landscape in two ways.
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First, the power of the water moving across a landscape cuts and erodes its channel.
As it does this, the river shapes its landscape by growing in size, meandering across
the landscape, and sometimes merging with other rivers forming a network of
braided rivers. The paths rivers take depend on the topology of the area and the
underlying geology or rock structure found where it's moving.
In addition, as the river carves its landscape it carries the sediment it
erodes as it flows. This gives it more power to erode as there is more friction in the
moving water, but it also deposits this material when it floods or flows out of
mountains onto an open plain in the case of an alluvial fan (image).
The mass movement process, also sometimes called mass wasting, occurs
when soil and rock moves down a slope under the force of gravity. The movement
of the material is called creeping, slides, flows, topples, and falls. Each of these is
dependent on the speed of movement and composition of the material moving.
This process is both erosional and depositional.
Glaciers are one of the most significant agents of landscape change
simply because of their sheer size and power as they move across an area. They are
erosional forces because their ice carves the ground beneath them and on the sides
in the case of a valley glacier which results in a U-shaped valley. Glaciers are also
depositional because their movement pushes rocks and other debris into new areas.
The sediment created by the grinding down of rocks by glaciers is called glacial
rock flour. As glaciers melt, they also drop their debris creating features like eskers
and moraines.
Weathering is an erosional process that involves the chemical break down
of rock (such as limestone) and the mechanical wearing down of rock by a plant‘s
roots growing and pushing through it, ice expanding in its cracks, and abrasion
from sediment pushed by wind and water. Weathering can for example result in
rock falls and eroded rock like those found in Arches National Park, Utah (2770).
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Text 26
The valley of geysers
A lot of wonderful sites are preserved in the Kronotsky Nature Reserve
but none of them is comparable with the uniqueness of the Valley of Geysers an indisputable world miracle.
The Kronotsky Nature Reserve is located on the southeastern
Kamchatka Peninsula, within the boundaries of the Eastern Volcanic Range.
The nature reserve was established as a wildlife refuge in 1882. The area was
expanded and became a full national park in 1934. Even so, there was no
knowledge of its geysers until 1941.
The Valley of Geysers is a canyon four kilometers wide, 400 meters
deep, and eight kilometers long, through which Geyzemaya River flows. There are
more than 440 geysers and many thermal springs, which are grouped in nine
clusters. Here we can see all known forms of hydrothermal activity, including
active and pulsating springs, hot pools, geysers, mud pots, and volcanic mud.
Geysers are natural hot springs with a permanent rhythmical activity and are
quite rare. The gushing of the hot spring is the result of a lot of factors: the form
and depth of the subterranean channel, the pressure, the flow of the cold waters
and the amount of the overheated steam. Geysers activity also depends on the
amount of surface waters, for instance precipitation, penetrating into the depths
of the ground. Steam and gas from the magmatic heart warm the water, it
boils and erupts to the surface through the ground cracks. The cycle of geyser
activity consists of several phases. During the initial phase, water fills an
underground basin and then a pool located at ground level. On its way up to the
surface, the superheated water depressurizes and starts boiling. The water
converts into vapour and increases its volume very rapidly, so the geyser starts
exploding. These eruptions are very loud. The fountains of hot water may be
vertical or slanted. After eruption comes the evaporation phase, and when the
vapour disappears it leaves the drying empty mouth of a geyser (1983).
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Text 27
The Carbon Cycle
There is a relationship between the two major metabolic processes of
photosynthesis and cellular respiration. Cellular respiration releases carbon
dioxide, which is used as a raw material in photosynthesis. Photosynthesis in
turn releases oxygen used in respiration. Animals and other heterotrophs depend
on green organisms for organic food, energy, and oxygen. In the carbon cycle,
organisms exchange carbon dioxide with the atmosphere. On land, plants take up
carbon dioxide via photosynthesis and incorporate it into food used by
themselves and heterotrophs. When organisms respire, some of this carbon is
returned to the atmosphere in the molecules of carbon dioxide. In aquatic
ecosystems, carbon dioxide from air combines with water to give carbonic acid,
which breaks down to bicarbonate ions. Bicarbonate ions are a source of carbon
for algae. When aquatic organisms respire, they release carbon dioxide that
becomes bicarbonate (HCO3). The amount of bicarbonate in water is in
equilibrium with amount of carbon dioxide in air.
Living and dead organisms are reservoirs of carbon in carbon cycle,
shown in Figure 7. More than 800 billion tons of carbon are in the world's biota,
mainly in cells of trees. An additional 1,000 to 3,000 billion tons of carbon
occurs in plant and animal remains in the soil. Fossil fuels, such as coal,
petroleum, and natural gas, were formed during various times of the geologic
past when exceptional amount of organic matter were rapidly buried in an
environment that locally lacked biologic activity. Inorganic calcium carbonate
(the minerals calcite and aragonite, CaCO3) accumulates in limestone and the
calcite of shells.
Human burning of fossil fuels and wood has increased the amount of
carbon dioxide released into atmosphere to 42 billion metric tons in only 22
years. Since human activity in 22 years probably released 78 billion metric tons,
36 billion metric tons were probably absorbed in oceans. Increased carbon
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dioxide levels may increase the greenhouse effect, where such gases allow the
Sun's radiant energy to pass through to Earth where it is absorbed and reradiated
as heat. Instead of radiating fromthe earth back into space, this heat is then
trapped on Earth, perhaps causing or contributing to global warming.
Excess output occurs when biomass is suddenly released, such as in slash
and burn agriculture. Excess input commonly occurs from agricultural increase
in organic fertilizer and other nutrients into an ecosystem. Generally speaking,
the faster matter cycles, the faster it can recover from human intervention.
Recently, speculation has centered on the interconnection of
biogeochemical cycles and their possible roles in a "superorganism" that James
Lovelock has called Gaia, after the ancient Greek Earth goddess. While an
intriguing notion, the degree of organization of these cycles is not as complex or
integrated as the cells in a body. Gaia remains controversial hypothesis that
continues to generate speculation and research both pro and con (3037).
Text 28
Human technology and population growth can directly and indirectly
disturb the biosphere. They key question now is: can humans cause global
climate change? The human population has experienced phenomenal exponential
growth since the Industrial Revolution. Modern agriculture and medicine have
increased growth rates for our population, resulting in over 90 million people
added each year. United Nations estimates indicate a human population of 10
billion may exist by the end of the twenty-first century.
Human populations are in a growth phase, shown in Figure 8. Since
evolving around 200,000 years ago, our species has proliferated and spread over
the Earth. Beginning in 1650, the slow population increases of our species
exponentially increased. New technologies for hunting and farming have
facilitated this expansion. It took 1800 years to reach a total population of 1
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billion, but only 130 years to reach 2 billion, and a mere 45 years to reach 4
billion.
Two Classes of Countries
The developed countries are those that industrialized first, such as the
United States, Canada, Japan, Russia, Australia, New Zealand, and all of Europe.
These countries have twenty-two percent of the world's population, but consume
nearly eighty percent of the energy and resources. Waste and pollution are also
greater in proportion to use of resources.
The developing countries have seventy-eight percent of the population,
but use only twenty percent of the Earth's resources. These countries include
most of Africa, South America, India, and China. Most people in these coluntries
have a lifestyle far below that of the inhabitants of the developed countries. As
developing contries expand their economies, their people will strive to achieve
the lifestyle of consumption and waste that we in developed countries take for
granted. For instance, in China the bicycle remains the method of transportation
for most people, but more and more motorcycles and cars are owned by the
increasing affluent entrepenuers and government officials. When I visited the
faculty and students at Wuyi University (China) in 1998, only a few of the
faculty had motor bikes. A colleague of mine visited the same university in the
summer of 2002 and reported that almost all faculty had motor bikes.
Industrialization is driven by energy consumption from coal, petroleum,
and natural gas, otherwise known as fossil fuels. Fossil fuels formed by
decomposition and alteration of the remains of plants, protists, and animals over
a time span of several million years. These sources are considered nonrenewable
since they are in limited supply in terms of human-scale time. Oil (petroleum) is
the fuel most widely used, both as starting material for making gasoline and for
other products. Historically coal was the first fossil fuel used in the
European/American Industrial Revolution of the 1800s. Petroleum soon replaced
109
coal, and has remained the mainstay of the energy fix needed by industrialized
societies (2980).
Text 29
Pollution
Pollution is any environmental change that adversely affects the lives and
health of living things. Burning fossil fuels results in hydrocarbons, carbon,
nitrogen and sulfur oxides, and particulates. Automobiles consume one-third of
the world's production of oil and are the chief source of air pollution. Some
scientists estimate there will be four times more automobiles in the world by
2025. Industrially produced halogens and the use of nitrogen fertilizers also
influence the atmosphere in a negative manner.
Sources of energy that are relatively nonpolluting exist. However, these
nonpolluting energy sources are not as commonly used as fossil fuels. Solar
energy does not add additional heat to the atmosphere, although the production
of solar panels may contribute to pollution. Solar panels, often mounted on
rooftops, absorb and move rooftop heat into water circulating within the panels.
Photovoltaic (solar) cells produce energy directly from sunlight, although the
cost of this energy is several times what conventional (fossil) fuel-generated
electricity costs.
Falling water is used to produce electricity in hydroelectric dams, asshown
in Figure 9. However, most dams would not be compliant with newer, more
strict environmental regulations. The damming of rivers to generate power (and
hold water for irrigation and other purposes) can lead to local extinctions or
declines in native fish populations. Water that id dammed up no longer freely
flows, placing wetland habitats downstream from the dam at risk. The numerous
dams built along the Salt and Verde Rivers in Phoenx, Arizona (USA) have led
to a reduction of downstream biodiversity as once perenniel streams now flow
only seasonally. Construction of the Glen Canyon Dam on the Colorado River in
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northern Arizona (shown in Figure 10) has led to vegetaion and other changes
inside Grand Canyon Nartional Park. The Three Gorges Dam being currently
built along the banks of the Yangtze River in China will displace over two
million people, flood areas that have been inhabited for over 10,000 years, as
well as disrupt the breeding patterns of the Yangtze sturgeon. When complete,
this dam will generate enough power every day to light a city the size of Los
Angeles, adding new power to the Chinese economic expansion (2297).
Text 30
Temperatures, Greenhouses, and Climate Changes
The average temperature of the Earth has risen by 0.5 degrees C over the
past one hundred years. Although a long-term rise of two degrees would seem
minor, this is thought sufficient to completely melt the glacial ice caps in
Antarctica and Greenland, causing global sea-levels to rise 100 meters. This can
alter climate patterns such as rainfall, ocean currents, and climate zones. Climate
changes can have biological (such as causing migrations) as well as geopolitical
and economic consequences.
Earth's climate fluctuates on both short-term and long-term time scales.
There have been periods of Earth history with higher average annual
temperatures than we have today, as well as the reverse condition, when glaciers
covered extensive expanses of the Northern and/or Southern hemispheres. We
are currently between ice ages, the last of which ended nearly 10,000 years ago.
Climate fluctuations have left evidence in the distribution of fossils, living forms
and their close relatives, and locations of certain types of sedimentary rocks.
Studies of fossils and the sedimentary rocks they occur in have led to estimates
of temperature. Paleoecology is the branch of science that deals with such data in
an attempt to reconstruct the evironments of the distant (and not so distant) past.
Some scientists are concerned that global climate will warm at a rate ten
times faster than it has in the past. Composition of the minor components of the
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