Demographic Concepts and Population Transition Stages in Human Geography

MDC (More Developed Country)

A country with high economic development, industrialization, and standard of living. Example: USA, Germany, Japan

LDC (Less Developed Country)

A country with low economic development, high birth rates, and lower standards of living. Example: Afghanistan, Niger, Haiti

Demography

The scientific study of human populations, including size, structure, and distribution

Overpopulation

When the number of people exceeds the capacity of the environment to support them. Example: parts of India or Bangladesh

Humans distributed across Earth's surface

Humans are unevenly spread; some areas densely populated, others sparsely populated

Concentration vs Density

Concentration = how population is spread (clustered vs dispersed); Density = number of people per area; both show population distribution

Four major population regions (2/3 of world population)

East Asia, South Asia, Europe, Southeast Asia

Other population clusters

Northeastern USA, Nigeria, Brazil's southeastern coast

Ecumene

Portion of Earth's surface occupied by permanent human settlement

Arithmetic Density

Total population ÷ total land area

Physiological Density

Population ÷ arable land

Agricultural Density

Number of farmers ÷ arable land

CBR (Crude Birth Rate)

Number of live births per 1,000 people per year

CDR (Crude Death Rate)

Number of deaths per 1,000 people per year

NIR (Natural Increase Rate)

CBR − CDR = population growth rate (excluding migration)

Doubling Time

Time it takes for a population to double at current NIR

NIR in LDCs vs MDCs

LDCs = high NIR due to high birth and declining death rates; MDCs = low NIR

Total Fertility Rate (TFR)

Average number of children a woman will have in her lifetime

Infant Mortality Rate (IMR)

Number of infant deaths (under 1 year) per 1,000 live births

Life Expectancy

Average number of years a person is expected to live

Demographic Transition Model (Stage 1: Low growth)

High birth & death rates → population stable

Demographic Transition Model (Stage 2: High growth)

High birth, declining death → population grows rapidly

Demographic Transition Model (Stage 3: Moderate growth)

Declining birth, low death → population growth slows

Demographic Transition Model (Stage 4: Low growth)

Low birth & death → population stable or declining

Agricultural Revolution

Development of farming → allowed human populations to grow

Industrial Revolution

Technological advances → economic growth and urbanization → lower death rates

Medical Revolution

Modern medicine → reduced mortality → increased life expectancy

Zero Population Growth (ZPG)

When CBR = CDR → NIR = 0

Population Pyramid

Graph showing population by age and sex

Dependency Ratio

Ratio of non-working (young + old) to working-age population

Sex Ratio

Number of males per 100 females in a population

Malthus & Overpopulation Hypothesis

Population grows faster than food supply → famine likely; critics argue food production can increase faster than population

Declining Birth Rates

Caused by urbanization, education, and access to contraception

Epidemiology

Study of diseases and their effects on populations

Epidemiologic Transition (Stage 1)

Pestilence & famine (example: Black Death)

Epidemiologic Transition (Stage 2)

Receding pandemics (example: Cholera in 1800s Europe)

Epidemiologic Transition (Stage 3)

Degenerative diseases (heart disease, cancer)

Epidemiologic Transition (Stage 4)

Delayed degenerative diseases (modern medicine prolongs life)