Реферат на тему World Population Essay Research Paper World population
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World Population Essay, Research Paper
World population, which reached 5.4 billion in mid-1991, is growing faster than
ever before: three people every second, more than 250,000 every day. At the beginning of
the decade (1991) the annual addition was 93 million; by the end (1998) it will approach
100 million. At this rate the world will have almost a billion more people (roughly the
population of China) by the year 2001.
Population and development are closely aligned. In Population: A Megalopolis is
Born, Melvyn Weslake sees these factors as being inextricably linked and having an
immeasurable impact on the future of this planet. He stated:
World Population will increase each year during the 1990 s by the equivalent of
Mexico s. This growth, which is overwhelming in the South, poses a threat to the
environment and stable development.
But what does this dynamic rate of growth really mean? Can we visualize its
impact? What can be done to impede its rate of growth/or reduce the fallout? And what is
being done?
Implications
The Brundtland Commission (1987) suggests the population is about not just
numbers of people, but how those numbers relate to available resources. The Commission
concluded that sustainable development could only be pursued if demographic
developments are in harmony with the changing productive potential of the ecosystem.
This question of balance is seen at the root of the problem. The capacity to
support a rapidly growing world population is thought to be clearly insufficient. This
despite advance in productivity made through developments in technology, most notably
the Green Revolution .
The truth may be that the prophecies of some visionaries may be more realistic
than we would like to believe:
h
h The Malthusian vision sees population growth ultimately overwhelming the food supply (unless checked by rising death rates brought on by famine, pestilence, disease, or war), and
h Garrett Hardin s dire parable in The Tragedy of the Commons demonstrates how social values and over-population can contribute to the degradation of the physical environment (Science, 1968).
What Drives Population Growth?
Modern demographers make projections about the growth of the human species in
much the same way that our friend Thomas Malthus did in the early 19th century,
but with some significant differences. Today, projections are based on sound
census data. And we now calculate population growth in the millions with
medium variants of absolute population for the 21st century in the billions.
The science of demographics has clarified population growth into understandable
components. The basic elements are:
h Birth and death
h Life expectancy, and
h Fertility (fecundity)
While these in turn determine:
h Growth rates
h The age distribution of the population, and
h The absolute population size.
These factors are useful for understanding what drives growth and for targeting
programs for population control. However, when demographic projections are
tied to impact, more meaningful information results. It is only when we relate
population data to a particular context can we appreciate its importance on future
and global development.
Now I ll briefly talk about population growth in the developing world, placing it
in the context of environmental sustainability, economic development and the
urban challenge.
The Developing World
The rate of population growth in the developing world is a very real concern and
will have repercussions long into the future. The population of developing
countries has more than doubled in 35 years, increasing from 1.7 billion in 1950
to 4.1 billion in 1990. By the year 2000, it will grow to nearly 5 billion (out of an
expected world total of 6.26 billion).
This means that as much as 97 percent of global population growth is
projected to take place in developing countries in Africa, Asia and Latin America
between now and the year 2020-within countries least able to absorb growing
numbers of people.
Cynthia Green found that consumption patterns and preferences are as
important as numbers of consumers. (The Environmental and Population Growth:
Decade for Action). Both Green and the Commission point to the developed
world as a larger threat to our world in the near and medium future than
population growth.
Environmental Sustainability
Cynthia Green had identified how pressure exerted by expanding population (and
their economic behavior) impact on the environment of developing countries. The
overall result is characterized by serious resource depletion. She found that the
pressure to grow more food and cash crops led to clearing the land that resulted in
degradation, loss of top soil, erosion, desertification, as well as, atmospheric and
climate change. She also concluded that:
h The subsequent pressure on ecosystems promotes massive losses of trees, plants and animals, and threatens biodiversity.
h Over-grazing and the destruction of range lands result with the movement onto marginal and even fragile lands.
h Over-fishing is experienced
h Aquifers are tapped which can replenish only gradually
h Fuel needs drive deforestation and greater use of non-renewable mineral resources, and
h Increased water pollution becomes the product of agricultural run off, sewage, etc. and
Green s work highlights just a few of the dramatic changes being experienced as a
result of population growth. In Sharon Camp s paper Population: The Critical
Decade, she states:
The quality of life on earth increasingly threatened by a powerful and growing
ecological force. We humans are that force, ever more of us using ever more
materials, assaulting the environment with ever more machines, chemicals,
weapons, and waste.
That s in the long-term, in the short-term he projected that:
h Rapid population growth may force scarcity problems upon us (before substitutes or new technologies are put in place)
h An insufficient demand for labor may cause serious employment problems, and
h Weak economies unable to absorb labor may see greater migration to urban centres-and ultimately the exodus of a nation s intellectual wealth to more developed countries.
Population Policies
The results of massive population growth have caused most developing countries
to formulate national population polices. Today there are 128 countries, which
provide direct support for family planning, and 17, more which provide indirect
support.
These polices vary in scope. They range from simply addressing the
demographic statistics (e.g. balancing rural and urban populations, slowing the
actual birth rate) using simple incentives and disincentives, to more advanced
policies which address the macro-issues focussing on the links to economic and
social development. The assumption that economic development and fertility
decline are causally linked forms a basis for most population programming.
Countries which have adopted population polices, whatever their nature,
have registered significant reductions in fertility rates. Several sources concur
with this finding including an article in the December 1993 issue of the Scientific
American by Bryant Robey, Shea Rutstein and Leo Morris entitled The Fertility
Decline in Developing Nations. These authors have concluded that the greatest
successes occur when programs are supported by:
h Political leadership
h Business and commercial interests
h Religion
h Intellectual and community leadership, and
h From the people at large.
In countries with a more holistic approach to planning, the success may be
more sustainable. Networks of community health workers and clinics,
which pay close attention to primary health care, preventive medicine and
family planning, characterize such programs.
Another important focus for family planning is the target group
approach (i.e. focusing on women). A gender perspective emphasizing the
role of women in the society, in the family planning choices and in
realizing their full potential in society through education and employment
programs has also proved very successful (e.g. Kabeer 1992). The success
of family planning worldwide is laudable; birth rates have declined by one
third since the mid-1960s, from an average family size of 6.1 children to
3.9. Regardless, more than one-half of the developing world s population
will be under 25 in the year 2000.
Family Planning Techniques
The use of modern family planning techniques had grown from less than
10 percent in the 1960s (predominately by married couples) to 51 percent
today. However, there is still an unmet need for family planning with:
h An estimated 90-160 million couples affected in 1992, and
h 20-30 percent of married women wanting to avoid pregnancy yet not using contraception.
Sterilization is the most popular method followed by inter uterine devices
(IUD) and hormonal contraceptives. These three methods account for
about 75 percent of all use worldwide. Unfortunately for AIDS campaign,
only 4 percent of married couples in developing countries use condoms.
The options for an unwanted pregnancy in the developing world
are very harsh: an estimated 36 to 53 million induced abortions occur
annually worldwide, at least half of them developing countries, and about
33 million are legal abortions (with some 15 million in developing
countries) suggesting that 3 to 10 million are performed illegally in
developing countries.
Complications from abortion alone kill an estimated 200,000
women per year in developing countries, amounting to 20 percent of all
material deaths (Outlook, Impact of Unsafe Abortion in the Developing
World, volume, 7, number 3, 1989).
Who s doing what?
Total funding for population is estimated by UNFPA at about $4.5 billion.
The UN projects that such funding will have to double by the end of the
century to keep growth on track.
Developing countries currently spend approximately $3.5 billion.
International population assistance from all donors amounts to an
additional $757 million (1989). This represents about 1.3. percent of total
ODA. About 129 developing countries receive international population
assistance.
According to UNFPA research, maintaining current rates of
population growth will require the extension of family planning services to
an additional 186 million couples (services are now provided to only 381
million couples). The best reference for sources of International
Population Assistance is produced by the United Nation Population Fund
(UNPF) Guide to Sources of International Population Assistance. An
accompanying volume entitled Inventory of Population Projects in
Developing Countries Around the World provides an overview of
population programming.