Unit IIPopulation (13-17%)

A.P. Human Geography

A. Geographical Analysis of Population

• Density, distribution, and Scale

Distribution

Population Clusters, DensityPopulation Density Population per unit of land area; for example, people per

square mile or people per square kilometer of arable land.

Arithmetic Density – the total number of people per a unit of land area. U.S. = 76/mi2; NYC=1,000,000/mi2; Australia = 7/mi2

Physiological Density – the total number of people per a unit of arable (farmable) land.

World and Country Population Totals

Distribution and Structure: 3/4 of people live on 5% of earth's surface!Total: 6.8 billion on planet as of March 5, 2010Current World Population Counter from U.S Census Bureau Five most populous regions and countries

REGION POPULATION COUNTRY POPULATION

• East Asia 1.6 billion China 1.3 billion• South Asia 1.5 billion India 1.1 million• Europe 1 billion U.S. 300 million• SE Asia 600 million Indonesia 250 million• E N. America &

Canada 275 million Brazil 188 million

How many shorties will the Luby’s have? Mmmm . .

Hog Wild

Scale

2. Consequences of various densities and distributions

An Aging WorldDiscussion

What are the implications of an aging population for:

1. The U.S. housing market?

2. Social security and pension funds?

3. Public financing of colleges and universities?

4. Global migration flows?

Overpopulation• When consumption of

natural resources by people outstrip the ability of a natural region to replace those natural resources.

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Technology, Energy Consumption, and Environmental Impact

There has been a dramatic increase in:• individual energy use over time: 3,000 kcal/person - 300,000 kcal/person• the power of technology to change the environment: think stone axe versus bulldozer versus atomic bomb.• The scope and severity of environmental impacts.

Luby’s future Softball team

3. Patterns of composition: age, sex, race, and ethnicity

Population J-Curve

4. Population and natural hazards: past, present, and future

B. Population growth and decline over time and space

1. Historical trends and projections for the future• Population Growth • The dominant issue in population geography remains growth. The world's

population is currently growing at a rate that is more than ten times the total estimated world population at the beginning of the Holocene and the bulk of this growth is occurring in the world's poorer countries.

• The Earth's environments and natural resources are strained as never before by the needs of a mush-rooming human population, a population that has more than doubled in the last 50 years.

• Problems resulting from unprecedented population growth became especially acute in the twentieth century. A continued high rate of population growth in the twenty-first century can have a calamitous impact, causing irreversible damage to the natural systems on which we depend for our existence and survival.

2. Theories of population growth, including the Demographic Model

Demographic Transition Model

Demographic Transition Model• Stage one (preindustrial/pre-agricultural)

– Crude birth/death rate high– Fragile, but stable, population

• Stage two (improved agriculture and medicine)– Lower death rates– Infant mortality rate falls– Natural increase very high

• Stage three (attitudes change)– Indicative of richer developed countries– Higher standards of living/education– Crude birth rate finally falls

• Stage four – Crude birth/death rates low– Population stable– Populations aging

Problems with the Demographic Transition

Model• based on European experience, assumes all countries will progress to complete industrialization• many countries reducing growth rate dramatically without increase in wealth – TV and family planning seem to be at work• on the other hand, some countries “stuck” in stage 2 or stage 3, particularly in Sub-Saharan Africa and Middle East

Thomas Malthus on Population

Malthus, responding to Condorcet, predicted population would outrun food supply, leading to a decrease in food per person.

Assumptions• Populations grow

exponentially.• Food supply grows

arithmetically.• Food shortages and chaos

inevitable.

An Essay on the Principle of Population, 1798

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Food

Food Population2 24 48 16

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(1743 – 1794)

• predicted that innovation, resulting increased wealth, and choice would provide food and resources in the future and lead to fewer children per family• believed that society was perfectible

Jean Antoine Condorcet

3. Patterns of fertility, mortality, and health

• Fertility The actual reproductive performance of an individual, a couple, a group, or a population. See general fertility rate.

• Mortality Deaths as a component of population change.

World Death Rates• Infectious diseases

– HIV/AIDS– SARS

• Degenerative diseases– Obesity– Tobacco use

• Epidemiological transition– Communicable diseases/pathogens in less developed

countries– Degenerative diseases in more developed countries

(obesity, heart disease, diabetes, cancer)

Life Expectancy

Life Expectancy

• Infant mortality rate

• Antibiotics/immunization

• Rapid increase throughout world

Adults and Children Living with HIV/AIDS, mid-2006

Infant Mortality Rate – the number of deaths of children under the age of one per thousand live births. The rate ranges from as low as 3 (Singapore, Iceland) to as much as 150 (Sierra Leone, Afghanistan). The U.S. rate is just over 6. High infant mortality tends to result in higher fertility rates as families seek “insurance” for the loss of children.

4. Regional variations of demographic transition

• Most current and future growth is taking place in developing countries, which have experienced only a partial demographic transition.

                                                                                  

Figure 7: Projected World Population Growth

5. Effects of Population Policies

New Influences on Birth Rates

Family planning programs Contraceptive technology Role of mass media

Population Control Obstacles

– Manufacture/distribution expense

– Religion– Low female status– Preference for male

children

C. Population Movement

• 1. Push and Pull Factors

• "Push-Pull" Hypothesis A migration theory that suggests that circumstances at the place of origin (such as poverty and unemployment) repel or push people out of that place to other places that exert a positive attraction or pull (such as a high standard of living or job opportunities).

2. Major voluntary and involuntary migrations at different scales

Involuntary

Trail of Tears 1830-35

Voluntary