Chapter 5. Human Population

Geog415

Dr. Hengchun Ye

Population dynamics: increases due to births and immigration and decreases through deaths and emigration.

Birth rate (crude birth rate): the number of deaths per 1000 people in a population in a given year.

Death rate: the number of deaths per 1000 people in a population in a given year.

Both birth rates and death rates are coming down worldwide, but death rates have fallen more sharply than birthrate. 219,000 birth/day with 97% in developing countries.

Annual rate of population change: (birth rate-death rate)/100person *100%

Developing countries have higher net birth rate (23-8) than developed countries (11-1).

Exponential population growth has not disappeared but is occurring at a slower rate.

Good news: the annual population growth dropped by almost half between 1963-2004.

But during the same period, the population base doubled from 3.2 billion to 6.4 billion.

Population growth in developing country was 1.5%, in developed country it was 0.1% (15 times difference)

The average world population growth is 1.3% (81 million=add another New York city every month= add another Germany every year)

Three countries with the largest number of people:China (1.3 billion in 2006; 1 in every 5 people in the world); India (1.1 billion; 1

in every 6 people), United States (300 million; 4.5% of world population).The medium projection for population in 2050 is 8.9 billion, Can the world

provide an adequate standard of living without causing widespread environmental damage in 2050?

Global Fertility rateFertility: the number of birth that occur to an individual woman or in a population1. replacement-level fertility: the number of children a couple must bear to

replace themselves (2.1 in developed countries and 2.5 in some developing countries; mostly because

some female children die before reaching their reproductive years)2. Total fertility: the average number of children a woman typically has during her

reproductive years (2.8 global average; 1.6 in developed countries and 3.1 in developing countries)

During 1957, the peak of the baby boom after the World War II, the total fertility rate was 3.7 children per woman. Then declined and remain at or below the replacement level.Baby Boom period: 1946-64.

Life style changes in the United States during 20 century that lead to dramatic increases in per capita resource usage and larger ecological footprint

10 Factors affecting birth rates and fertility rates

1. Importance of children as a part of the labor force (in developing countries in rural areas)

2. Cost of raising and educating childern (more costly in developed countries because they enter labor force in late teens or 20s)

3. Availability of private and public pension systems (pensions eliminate parents need to have many children to help support them in old age)

4. Urbanization (people in urban have better access to family planning services and no need children’s support in work)

5. Educational and employment opportunities available for women (education and outside paid employment reduces birthrate). (In developing countries, non-educated country side woman has 2 more children than these have a secondary school education)

6. Infant mortality rate (lower mortality rate areas have smaller number of children)7. Average age at marriage (or average age at which women have their first child)

(woman had first child at 25 years or older has fewer children)8. Availability of legal abortion (190 million woman become pregnant, about 46

million of these get abortions; 26 million are legal and 20 million illegal)9. Availability of reliable birth control methods10. Religion beliefs, traditions, and cultural norms

Factors affecting decreased death rate

1. Increased food supplies

2. Better nutrition

3. Advances in medicine

4. Improved sanitation and personal hygiene

5. Safer water

Indicators for overall health of people in a country or regions

1. Life expectancy: average number of years a newborn infant can expect to live2. Infant mortality rate: the number of baby of every 1000 born who die before their first birthday Good news: global life expectance increased from 48 to 67 years (76 in developed countries and 65

in developing countries) between 1955-2004. In United States from 47 to 77 and projected to reach 82 by 2050.

Bad news: Africa, poorest and least developed country is 49 years or less (due to AIDS)Infant Mortality is the best measure of a society’s quality of life because it reflects the general level of

nutrition and health care.High infant mortality rate indicates insufficient food (undernutrition), poor nutrition (malnutrition) and a

high incidence of infectious disease (from contaminated drinking water and weakened disease resistance from undernutrition and malnutrition)

Good News: infant mortality rate dropped from 20 per 1000 live birth to 7 in developed countries and from 118 to 62 in developing countries between 1965-2004.

Bad News: 8 million infants (most in developing countries) die of preventable causes during the first year of live (22000 per day)

In US, infant mortality rate is 6.7 in 2004. Some 40 countries had lower rate than U.S.Factors: 1. inadequate health care for poor women during pregnancy and for their babies after birth2. Drug addiction among pregnant women3. A high birth rate among teenagers.

Immigration issuesCurrently legal and illegal immigration account for

about 41% of the country’s annual population growth. By 2050, Latinos are projected to make up one of the every four people in the United States.

Cons: providing immigrants with public services makes

that US a magnet for the world’s poor; if reduced, allow US stabilizes its population sooner and help reduce the country’s environmental impact

Pros: growth and cultural diversity of the US; reduce

immigration would diminish the historical role of the US as a place of opportunity for the world’s poor and oppressed; take low paying jobs and create jobs. It is projected that higher immigration levels will be needed to supply enough workers as baby boomers retire after 2020.

Population structure

Age structure: the distribution of males and females in each age group.

3 age categories: pre-reproductive (0-14); reproductive (15-44), and post-reproductive (45 and up)

The number of people under age 15 is the major factor determining a country’s future population growth. About 30% of people in the planet were under 15 years old in 2004.

For US, baby boom affects age structure. It makes up half of all adult American. The retirement of baby boomers is likely to create a shortage of workers in US. Smaller number of people in the baby-bust generation that followed them to pay higher income, health-care, and Social Security taxes. On the other hand, baby-buster generation have an easier time for competing for educational opportunities, jobs, and services, wages will be up due to labor shortage for jobs requiring education or technical training beyond the high school.

Rapid population decline can lead to severe economic and social problems. It induces sharp rise in proportion of older people, they consume an increasing larger share of medical care, social security funds, and other costly public services funded by a decreasing number of working taxpayers.

AIDS tragedy: disrupts a country’s social and economical structure by removing large numbers of young adults from its age structure

Comparison of key demographic indicators for three countries

Controversy: population control

Can the world support the adequate standard of living for 2.5 million more people without causing widespread environmental damage?

1. The earth is overpopulated2. Encourage population growth to help stimulate economic growth by having more consumers.

Cons:population control is violation of religion beliefs; intrusion into their privacy and the personal freedom;

or genocide to keep their numbers and power from rising in some minorities in developed countries or developing countries.

Pros: we fail to provide the basic necessities for one out of six people on the earth, how can we do it with

more people? Higher death rate because of declining health and environmental conditions (Africa); increased resources use and environmental harms produce increased large ecological footprints (China, India, etc). Increase environmental stresses such as infectious disease, biodiversity losses, loss of tropical rainforests, fisheries depletion, increasing water scarcity, pollution of the seas, and climate change. Intensifying existing environmental and social problems.

Accepted Opinion:People should have freedom to produce as many children and they want, but only if it does not

reduce the quality of other people’s lives now and in the future, either by impairing the earth’s ability to sustain life, or by causing social disruption. Limiting the freedom of individuals to do anything they want, in order to protect the freedom of other individuals.

Economic development help reduce birth ratesDemographic transition: a hypothesis of population change: as countries become

industrialized, first their death rates, then their birth rates decline. Transition takes place in 4 distinct stages.

1. Preindustrial stage: little population growth (harsh living conditions; high birth rate and high death rate)

2. Transitional stage: death rates drop and birth rates remain high, rapid population growth

3. Industrial stage; slower population growth. Birth rate drops and approaches the death rate (medical advances, modernization widespread) (most developed countries and a few developing countries are at this stage)

4. Postindustrial stage: birth rate declines further, equaling the death rate and reaching zero population growth; then birth rate falls below the death rate and population decreases slowly (40 countries or 14% of the world population have entered this stage

Concerns: rapid increase in population will outstrip economic growth and overwhelm some local life support systems. This would cause some countries to be caught in demographic trap at stage 2 (Africa due to HIV/AIDS epidemic are falling back to stage one)

Lack of skilled workers needed to produce the high-tech products necessary to compete in today’s global economy and lack of capital and other resources that allow rapid economic development (sharp rise in debt to developed countries, income are used to pay interests rather for improving social, health, and environmental conditions)

Solution for population increase:1. Family planning: educational and clinical services that help couples choose

how many children and when to have them2. Education, job and rights for woman: education, paying job outside the

home, and living in societies where their rights are not suppressed will help women to have fewer and higher quality children. This will reduce poverty and slow environmental degradation.

Case studies in India and ChinaIn India, modest success in population

control after over 5 dedads of effort. Indian women have an average of 3.1 children. Strong preference for male children; only 43% women use modern birth control

In China, (since 1970 government-enforced program to cut birth rate in half and sharply reduce its fertility rate), free sterilization, contraceptives, abortion, more than 83% married women use modern contraception.

Bad: gender imbanance in China’s population (projected 30-40 million surplus of men by 2020)

Population distribution problemsUrban growth and problems: half of the world people live in densely populated urban

areas as rural people have migrated to cities to find jobs, food, housing, better life, entertainment, and freedom from religious, racial, and political conflicts. Some are pushed from rural areas by factors such as poverty, lack of land to grow food, declining agricultural jobs, famine, and war.

Trends:1. The proportion of the global population living in urban area is increasing2. The number of large cities is mushrooming3. Urban growth is much slower in developed countries4. Poverty is becoming increasing urbanized as more poor people migrate to urban

areas, mostly in developing countries.Urban Sprawl: growth of low-density development on edges of cities and towns, gobbles

up surrounding countryside-frequently prime farmland or forests-and increases dependences on cars.

Bad: unsustainable, huge outputs of solid wastes, heat, pollutants, greenhouse gases, noise, etc.

Good: concentrating most of the population in urban areas has helped protect the country’s biodiversity by reducing the destruction and degradation of wildlife habitat

Offer more job opportunities and better education and health (better access to medical care, family planning, education, social services, recycling is more economically feasible)

Population problems and solutions in the news

http://www.msnbc.msn.com/id/44990504/ns/us_news-life/