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Human Geography By James Rubenstein. Chapter 2 Key Issue 3 Why is Population Increasing at Different Rates in Different Countries?. Demographic Transition. The five stages of change in populations through which society progresses. Stages of Demographic Transition. Stage 1: Low Growth
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Human GeographyBy James Rubenstein Chapter 2 Key Issue 3 Why is Population Increasing at Different Rates in Different Countries? S. Mathews
Demographic Transition The five stages of change in populations through which society progresses. S. Mathews
Stages of Demographic Transition • Stage 1: Low Growth • Stage 2: High Growth • Stage 3: Moderate Growth • Stage 4: Low Growth • Stage 5: Negative Growth* * not in text S. Mathews
World Populations and Growth Rates S. Mathews
Stage 1: Low Growth S. Mathews
Stage 1 Characteristics • Humans were hunters and gatherers • NIR was essentially zero • WP was perhaps ½ million • The WP increased and decreased with the availability of food S. Mathews
Agricultural Revolution A time, between 8000 B.C. and 1750 A.D., when human beings domesticated plants and animals. S. Mathews
Effects of the Agricultural Revolution • A larger, more stable supply of food • More people could survive • WP increased from about 5 to 800 million • War and disease still took toll • Still Stage 1 until 1750 A.D. • No country is at stage 1 today S. Mathews
Stage 2: High Growth S. Mathews
Industrial Revolution A conjunction of major improvements in industrial technology that transformed the process of manufacturing goods and delivering them to market. S. Mathews
Stage 2 Characteristics • Unprecedented level of wealth • Increased agricultural production fed the rapidly growing population • people freed to work in factories • Improved sanitation and personal hygiene S. Mathews
Medical Revolution Medical technology invented in Europe and North America, diffused to LDCs of Africa, Asia, and Latin America. S. Mathews
Medical Revolution • Edward Jenner developed a smallpox vaccination in 1796 • Penicillin and other vaccines and insecticides were developed to combat diseases S. Mathews
Effects of the Industrial and Medical Revolutions • CDR suddenly plummeted • WP grew 10 times faster • At first, accelerating population growth • then, growth rate slowed, but large gap remained between births and deaths. S. Mathews
Stage 2 Transition Dates • Europe and North America about 1800 • Africa, Asia, and Latin America about 1950 S. Mathews
Stage 3: Moderate Growth S. Mathews
Stage 3 Characteristics • Begins with a sudden decline of CBR • CBR is still greater than CDR • The NIR is more modest than Stage 2 • CDR declines due to new technology • CBR changes due to social changes S. Mathews
Social Changes • People choose to have fewer children • Delayed reaction to decline in IMR S. Mathews
Economic Changes • Children living on farms shared the chores • As technology improved, people moved from the farm to the city • Children living in the cities are not economic assets to their families • Urban homes too small to accommodate large families S. Mathews
Stage 3 Transition Dates • Europe and North America moved in the first half of the twentieth century • Asia, and Latin America in recent years • Africa still in Stage 2 S. Mathews
Stage 4: Low Growth S. Mathews
Zero Population Growth (ZPG) When the CBR and CDR are near equal, the NIR approaches zero (measured by a lack of change in the TFR over a long period). S. Mathews
Stage 4 Characteristics • A country with many immigrants must decrease TFR to achieve ZPG • CBR can be slightly higher then CDR, with some females dying before they reach childbearing years. S. Mathews
Stage 4 Transition Dates • Most of Europe reached Stage 4 since 1970s • The United States TFR went below ZPG (replacement level of 2.1) in 2000, but immigration prevents them from reaching Stage 4 S. Mathews
Social Customs in Stage 4 • More women enter work force • Working parents must employ preschool care during work hours • Wider variety of birth-control • Participation in entertainment and recreational activities not suitable for children S. Mathews
Stage 5:Negative Growth S. Mathews
Negative Growth The CBR is lower than the CDR S. Mathews
Negative Growth as result of fifty years of Communism in some Eastern European, most notably; • Russia • Hungary • Germany (Eastern) S. Mathews
Reasons for Negative Growth • Very strong family planning programs • Deep-seated pessimism about having children in an uncertain world S. Mathews
The Demographic Transition in England • England has reached Stage 4 • 1000 years of population information available • Boundaries unchanged • Migration limited S. Mathews
Stage 1 Characteristics • In 1066, population was 1 million • In 1250, the population declined from 4 to 2 million • By 1750, the population had reached only 6 million S. Mathews
Stage 2 Characteristics • By 1800, the CBR remained high, but CDR declined • Industrial Revolution increased food supply and improved health care • By early 1900s, population increased from 6 to 30 million (NIR = 1.4%) S. Mathews
Stage 3 Characteristics • Between 1880 and early 1900s • While CDR declined, the CBR declined rapidly • Between 1880 and 1970, the population increased from 26 to 49 million (NIR = .07%) S. Mathews
Stage 4 Characteristics • Since 1970s, CBR has varied between 12 to 14 per 1000, while CDR has varied between 10 to 12 per 1000 • Population has increased due to immigration from former colonies • Population is currently around 52 million S. Mathews
Population Pyramids A country’s stage of demographic transition gives a distinctive population structure which can be easily viewed in a population pyramid. S. Mathews
Population Pyramids A bar graph that displays a country’s population by age and gender groups. S. Mathews
Characteristics of Population Pyramids • population shown in five-year age groups • length of the bar represents % of total population in that group • males shown on left side and women on right S. Mathews
Age Distribution Structure of populations are important in understanding similarities and differences among countries. S. Mathews
Dependency Ratio The number of people who are too young or too old to work, compared to the number of people in their productive years. 0 – 14 (too young) 15 – 64 (productive years) 65+ (too old) S. Mathews
Dependency Ratio in Demographic Transition • 1:1 dependency in stage 2 • 1:3 dependency in stage 4 • 10:1 young to old in stage 2 • 1:1 young to old in stage 4 S. Mathews
Population Under 15 • In LDCs 1/3rd of population are under 15 (stage 2) • In European and North America, 1/5th of population under 15 (in/near stage 4) S. Mathews
The large percentage of children in stage 2 countries strain the resources to provide needed services to the dependent group. S. Mathews