AP HUMAN GEOGRAPHY CHAPTER 5

CLASS NOTES

Processes and Cycles of Population Change

The Population Explosion of the 20th Century

• 2.5 million years for the world’s pop. to reach 1 Billion,

• Only 200 more years to reach 6 billion

• Key to reducing population growth rates?

• WOMEN!!!– education– rights

Thomas Malthus ???

• British Economist

• Essay on Population, 1798

• World’s Population is increasing faster than the food supplies needed to sustain it

Malthus Theory

• Population increases at an Exponential rate

• Means of Subsistence (food supply) increases at an Arithmetic rate

Growth Types

Linear (Arithmetic) Growth

• Constant

• (arithmetic rate) 1, 2, 3, 4, 5, 6, etc.

Exponential (Geometric) Growth

• Compounded (doubling)

• 2, 4, 8, 16, 32, 64, 128, etc.

Pick a Side• Neo-Malthusian: Supports ideas of

Malthus– Inevitable stage in history– Human suffering greater than M. predicted

• Anti-Malthusian: not in agreement– Food production not linear> has become

exponential as well• Cultivated land increased• New seeds and fertilizers used (biotech, yield)

Natural Increase (pop.) ???

• Difference between # of births and # of deaths in a period

– Crude Birth Rate (CBR): live births per year per 1,000

– Crude Death Rate (CDR): # of deaths per 1,000 (mortality

rate)

High Birth & Death Rate

• High BR: • S. Asia, SW Asia, Sub-Saharan Africa

(50 per 1000) • Highest DR: • Africa

– Deteriorating health conditions– No Access

• Infant Mortality Rate: ???• die before 1st BDay

Low Birth Rate

• Low BR: Europe (15 per 1,000), N. America, Australia, China, Japan

• Low BR =

• modernization, industrialization, urbanization, education (women)

Total Fertility Rate (TFR)

• # of children born to women of child bearing age

• TFR’s are declining all over the world– China’s fell from 6.1 to 1.7 in just 30 years

• A TFR of 2.1 is needed to maintain stable population over time (60 countries below)

Past Limits on Population Growth (until 19th Century)

• (Malthus said we needed to check Pop.)

– Epidemics & Plagues (Black Death, AIDS)– Famines (weather)– Wars

• (Khmer Rouge killed 3 of 7 million people)

After 1800s…

– Marked increase in Pop. Growth rate in Europe

– 2nd Agricultural Revolution• Farming methods improved• Tools

– ***Industrial Revolution***• Sanitation, vaccines,

Demographic Change FormulaTo figure out the total POP. change• TP = OP + B – D + I – E

– TP : total population– OP: original population– B: births– D: deaths– I: Immigration– E: Emigration

Living Old…

• DEPENDENCY RATIO –

• Ratio of # of people either too old or too young to provide for themselves to the # of people who must support them through their own labor

• n : 100– n = the number of dependents

POPULATION PYRAMIDS(“Age – Sex” Pyramids)

• Instantly conveys the demographic situation in a country

• See what age group (of M & F) has what share of the population

POPULATION PYRAMIDS(“Age – Sex” Pyramids)

World POPULATION

What does this tell us???

What is happening to POP in each???

Nigeria 1963

Nigeria 2003

Demographic Transition Cycle MODEL

Demographic Transition (Cycle)4 STAGES MODEL

Development : BR / DR(Based on Europe Model of Growth (UK))

1. High Stationary Stage –

high fertility (BR), high mortality (DR), little long term POP growth

Farming, Mining

(poor, underdeveloped countries)

Demographic Transition Cycle MODEL

2. Early Expanding Stage –

high BR, declining DR

POP growth rate high

Food Supply & Country Stable, Trade

DTC con.

3. Late Expanding Stage -

Now declining BR, already low DR so continued POP growth

Industrialization, Urbanization

4. Low Stationary Stage –

low fertility, low mortality,

low POP growth rate

Modernization, Education, Women Rights

= CORE COUNTRIES (Rich, Industrialized)

Key Questions…• Why Unwise to assume

that ALL countries’ growth follows DTCM (Europe)?

• Stationary Population Level (SPL) (DTM Stage 5?)

• World’s pop. will stop growing in 21st Cen. (Will Stabilize)

–Why??? How???