Upload
lawrence-greer
View
217
Download
4
Embed Size (px)
Citation preview
Demography & Population
APES Ch 7
2
Two Demographic Worlds
Developing countries are poor (15%), young, and rapidly growing. India, China, Bolivia (S. America), Congo (Africa)
Contain 81% of world population, and will account for 90% of projected growth.
Incomes of 3$/person/day and less
Developed countries are wealthy (85%), old, and mostly shrinking. United States, Japan, France
Populations often expected to decline.
Developing Countries
Developing countries tend to have severe overpopulation. This leads to:
Deforestation
Bare soil
Native animals driven to extinction
Malnutrition, starvation, disease
About 81% of the world’s population falls in this category
Only use 12-25% of the world’s resources
3
Developed Countries
Developed countries, while smaller in size and growth, consume resources at a greater rate.
About 19% of the world’s population uses 88% of its resources. Creating 75% if the world’s waste.
Higher life expectancy, wealth, energy use, pollution and waste.
4
Developing and Developed Countries
5
Source: Holt Environmental Science, Arms, 2007
6
Estimated Human Population Growth
7
Measurements of Population Growth
Birth Rates - Number of births per 1000 women per year.
Developing countries = ~20
Developed countries = ~10
Total Fertility Rate –
Congo = 4.41 (developing)
India = 2.68 (developing)
U.S. = 2.1 (developed)
The replacement level is when you have 2.1 – 2.5 children per couple.
Theory of Demographic Transition
A four phase process that describes the transition of a country as it moves from a subsistence economy to industrialization and increased affluence, it undergoes a predictable shift in population growth. Phase 1: Slow Population Growth
Phase 2: Rapid Population Growth
Phase 3: Stable Population Growth
Phase 4: Declining Population Growth
Phase 1 – Slow Growth
Phase 1 (Pre-industrial):
Steady state – population will not change quickly
High birth & death rates (match each other)
Short life expectancy is short due to difficult and dangerous working conditions
High Infant mortality rate due to disease, lack of health care, & poor sanitation
Children are an asset – do jobs for family
Lesotho is in Phase 1 due to HIV/AIDS
Phase 2 – Rapid Growth
Phase 2 – Transitional Death rates decline while birth rates remain
high
CBR remains high due to population momentum as families still have many children & lag time to implement education & birth control measures.
Better sanitation, clean drinking water, increased access to food & health care reduce infant mortality rate CDR.
India is in phase 2 today
Phase 3 - Stable
Phase 3 – Industrial
Economy & educational systems improve
Family income increases; have fewer children & CBR falls
Having large numbers of children becomes a financial burden but cultural, societal, and religious norms may play a part
Both CBR and CDR decrease & population growth levels off.
USA and Canada are Phase 3
Phase 4 - Declining
Phase 4 – Post Industrial Declining population, high level of affluence
& economic development
Higher proportion of elderly people. Few people in labor force, pension programs, social security puts a tax burden on the working population
Japan, UK, Germany, Russia, and Italy are in phase 4
TFR increases after hitting a low. Such patterns can be seen in Norway, Italy, & US
Family Planning
Fertility rates decrease when:
Family income increases
Higher levels of education/affluence. Especially among females.
Delaying first pregnancy till older
Why?
Delay having children due to demands of school & work
Better access to birth control
Interact with partners as equals
Family planning – regulate the number and spacing of offspring
Family Planning
Effective family planning campaigns:
Kenya in 1970’s reduced TFR by half (from 8 to 4) in the 1990’s
Gov’t encouraged smaller families appealing to the idea that overpopulation lead to unemployment and use of condoms.
Thailand in 1970’s gov’t encouraged couples to practice birth control
Contraceptive use increased from 15 to 70% w/in 15 years
Growth rate fell from 3.2 to 1.6%; today rate is 0.6%
Family Planning Reduces Birth Rates and Abortion Rates
Advantages of Family Planning:
Increase the proportion of married women in developing countries who use birth control
50% drop in TFR since 1950
Reducing the number of legal and illegal abortions
Decreasing the risk of death form pregnancy
Unfortunately,
42% of all pregnancies in LDC’s are unplanned and 26% end in abortion.
Many women, 250-350 million, want to limit the number and determine the spacing of their children, but they lack access to services.
Family Planning Reduces Birth Rates and Abortion Rates
Future Goals:
Expanding family planning to include teenagers and sexually active unmarried women who are often excluded.
Pro-choice and pro-life groups to join forces in greatly reducing unplanned births and abortions, especially among teenagers
Programs to educate men about having fewer children and taking more responsibility for raising them
Increased research on developing new, more effective, and more acceptable birth control methods for men
Empowering Women to Reduce Birth Rates
Women tend to have fewer children when they have access to education and jobs outside the home and live in societies in which their rights are not suppressed.
Most analysts believe that women everywhere should have full legal rights and opportunity to become educated and earn income outside the home.
Not possible without a great deal of social changes in many of the male-dominated societies of today.
Population & the Environment
Population & economic development are not equally distributed around the world thus, human impact on natural resources are also unequally distributed.
People in developed countries may have 2 to 10 times the environmental impact as people in developing countries
Population disparity between rich & poor has accelerated in recent years
9 of the 12 most populous nations are developing countries
Populations of impoverished countries are increasing rapidly while affluent countries are stable or declining
Ecological footprint measures the effect of affluence (money, goods, property) on the planet. Measured in hectares.
The IPAT Equation
To estimate the impact of human lifestyles on Earth, environmental scientists developed the IPAT Equation:
Impact = Population x Affluence x Technology
IPAT Equation Conceptual representation of the factors that
influence environmental impact:
Population – straightforward effect on impact. Two people consume more than one
Affluence – not straightforward effect on impact. The more affluent a society is, the higher the environmental impact.
Technology – complicated; can either degrade an environment or create solutions to minimize impact.
CFC’s = safe & effective refrigeration but destroyed ozone
Electric cars reduce impact on environment
Millennium Ecosystem Assessment
Blue Print for sustainable development:
Completed in 2005 at request from UN
Global analysis of the effects of human population on ecosystem services such as clean water, forest products, and natural resources
Conclusions:
Human demand for ecosystem services led to a large and irreversible loss of biodiversity
Ecosystem sustainability threatened in population continues along current path
If we establish sustainable practices, we may be able to improve standard of living for a large number of people