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Transcript of Malthus s theory - 1.cdn.edl.io · Malthus’s theory The debate about population and resources...
Malthus’s theory
The debate about population and
resources originated in the work of an
English named Thomas Robert Malthus
(1766—1834), whose theory of
population relative to food supply
established resources as the critical
limiting condition upon population
growth.
Population growth grows geometrically while food
production increases arithmetically
Year Population Food Supply
1 100 100
20 200 200
40 400 300
60 800 400
80 1600 500
100 3200 600
120 6400 700
140 12800 800
160 25600 900
carrying capacity: the maximum number of users that
can be sustained by a given set of natural resources.
Population continues to rise in
certain areas of the world because
• Some people have limited access
to contraception
• Medical Revolution
• Some countries are still in stage 2
of the demographic transition with
a declining death rate
In many places there is not enough food
(world hunger, widespread famine)
• Failure to adopt modern agricultural
techniques
• Environmental degradation
(desertification, overgrazing,
clearcutting, soil erosion)
Population growth has NOT been
rising in many places
• declining birth rate
• expanded use of contraception
• political policies (one child)
• education/empowerment of women
• Many countries in 4th, &/or 5th
stages DTM
There is enough food
• mechanization, use of chemicals,
irrigation, Expansion of agricultural
lands
• (new technologies is too vague)
There has also been an increase in trade: ability
to distribute food to areas of need is much
greater than during Malthus’ time
• Improvements in transportation (highways,
containerization, refrigerated trucks)
• Improvements in food preservations
(refrigeration, packing, processed food)
3 Sides to the Population Debate
1. Neo-Malthusians (Antinatalist): High fertility
rate is one of the biggest problems facing the world
today
Developing countries have large numbers of
children and youth that will swell the
childbearing ranks for years to come
(Demographic momentum) causing economic,
social and environmental problems.
Negative Social aspects of rapid
population growth:
• Population growth may
outstrip a country’s ability to
provide social services to its
entire population.
• Poor education
• Housing shortages (squatter
settlements)
• Inadequate health care
• Crime
• War (caused by overuse/lack
of resources)
A forest once stood here, and Sumatran tigers hunted wild pigs and deer in its glades. As forests are cleared
for oil palm plantations, like this one near Longkib, Indonesia, tigers migrate in search of wild prey—or
target farm animals.
Government policies to address high
fertility rates:
• investments in family planning or
access to contraceptives
• investments in the education of girls
• Improve equality/rights of women
• investments in reproductive and child
health (if infant mortality decrease so
will the natural increase)
1990
• 58.8%
• 21.5
• 16.1
• 21.2
• 8.5
• 12.1%
• 79.4
• 9.4
• 5.4
• 5.2
• 0.5
• 20.5
Asia
China
India
Other Asia
Latin America
Africa
Sub-total
Europe
Former USSR
North America
Oceania
Sub-total
2100
•53.5%
•12.6
•16.7
•24.2
•9.6
•26.2%
•89.3
•3.9
•3.6
•2.8
•0.6
•10.9
.
2. Cornucopians:
Continued progress can be met by
advances in technology.
Fundamentally they believe that
there is enough matter and energy on
the Earth to provide for the
estimated peak population of about
9.22 billion in 2075.
Human creativity and innovation will provide
opportunities for people to overcome the limitations of
their environment.
Hydroponics
Ester Boserup argued
that population
determines agricultural
methods.
Farmers will adopt new
and modern methods to
keep up with demand
caused by an
increasing population
A major point of her book is that "necessity is the
mother of invention". It was her belief that humanity
would always find a way and was quoted saying "The
power of ingenuity would always outmatch that of
demand.”
The world population explosion is a thing of the past.
People should be having more children.
falling fertility rates have caused
• aging populations
• shrinking workforces
• inadequate demand for goods and
services
• intergenerational conflict
• immigration tensions(someone has to
work and pay taxes but they often bring a
different culture).
Paying for retirement is easy when the
population is growing and people don’t
live long. When it isn’t, there are three
unwanted choices
1. Raise taxes of workers (middle cohort)
2. Decrease benefits
3. Raise retirement age
What government can do to raise fertility rates:
• money for having children or tax breaks
• longer maternity leaves
• subsidized (government pays) day care
• day care at places of work
• shorter work days for women or part time
• telecommuting
Niger 10 million people the country with the
highest fertility rate 7.5 population will double by
2025 20.4 million
48 percent is ages 15 or younger
2 percent over 65
Bulgaria
8.2 million people with
the lowest
fertility rate 1.09
lose 1.2 million people
during the same
period, falling to 7
million.
17 percent under 15
16 percent of all
Bulgarians are ages 65
or older
This is geography: Different parts of the world have different rates of growth
Where people live influences how many children people have.
3. Marxist: Population is a political
issue group:
governments lack the
will to redistribute
wealth or the resources
to reduce poverty
4 Stages of epidemiological transition
Epidemiology is the study of the patterns, causes, and
effects of health and disease conditions in defined
populations
1.The Age of Pestilence and Famine: Where mortality is high
and fluctuating, precluding sustained population growth,
with low and variable life expectancy, vascillating between
20 and 40 years.
2. The Age of Receding Pandemics: Where mortality
progressively declines, with the rate of decline accelerating as
epidemic peaks decrease in frequency. Average life
expectancy increases steadily from about 30 to 50 years.
Population growth is sustained and begins to be exponential.
3. The Age of Degenerative and Man-Made Diseases:
Mortality continues to decline and eventually approaches
stability at a relatively low level. Life expectancy rises and
exceeds 50 years.