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Explore the history and consequences of China's One-Child Policy, shifts in population demographics, the Two-Child Policy, and global implications of human population growth.
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Environment & Ecology 007 Human Population
Human population: 7.5 billion (2017) Woodstock
2015 China: 1.38 billion India: 1.31 billion USA 356 million
1949 population 541.7 million • Mao Zedong saw population growth as a good way to fight the Soviet Union and the United States. • The Communists called on women to “breed for the motherland”. • The population grew very quickly after 1949.
Family Planning Prior to the One Child Policy • Early 1970s: “later-longer-fewer program”. • End of 1970s: “One is best, at most two, never a third”
Family PlanningOne Child Policy • 1981- population 1 billion • Regulations of the policy • Employers and neighborhood committees had to enforce guidelines. • Young people needed permission to get married. • The government monitored women’s menstrual cycles. • The use of birth control was required by the government. • All pregnancies must be authorized
Family PlanningOne Child Policy • Incentives • Monthly allowances • Free education and medical services • Disincentives • Fines • Repay awards
China’s natural rate of change has fallen China’s rate has fallen with fertility rates. It now takes the population 4 times as long to double as it did 25 years ago.
Consequences • Population growth slowed • Aging population • Imbalanced sex ratio • Psychological consequences: • Currently around 70 million single child. • 4-2-1 syndrome (4 grand parents – 2 parents – 1 child)
Age structure: “Graying populations” Demographers project that China’s population will become older over the next two decades.
Age structure: “Graying populations” China’s aging population will mean fewer working-age citizens to finance social services for retirees.
Sex ratios 100 females born to 106 males China: 100 females born to 117 males
Family PlanningTwo Child Policy • Oct. 2015 • Married couples would be allowed to have a second child, • Only 12% of eligible families applied to have a second child http://www.bbc.com/news/world-asia-34665539
How did we reach 7,500,000,000 people?
A few milestones • 10,000 b.c. agriculture • 1500’s new crops from Americas reach Europe • 1798 vaccinations • 1850 sewers were separated from drinking water, which was filtered and chlorinated • 1884 contraception • 1930 better nutrition, sanitation, health care • 1960 Green Revolution
Aloha Stadium holds 50,000 # of H. sapien 200,000 ybp 10,000
10,000 ybp 2.4 million people 1.8 million Not 1.8 million
Rise of agriculture • Syria-Palestine 9-10,000 years ago • Central American about 4-9,000 years ago • Chinese center about 8,500 years ago • New Guinean about 10,000 years ago • South American about 6,000 years ago • North American (Mississippi basin) between 2-4,000 years ago
Jenner & vaccination 1800
Contraception 1900-1950
A Square Meal Creamed, canned and frozen 1930’s Great Depression
Green revolution Higher yields Pesticides Heavy equipment Fertilizer Lots of irrigation
Growth Curves ? Exponential or logistic curve ? paramecium
The human population is still growing rapidly 1350 Agricultural Revolution Hunter/ Gatherer Industrial Revolution
https://ourworldindata.org/grapher/world-population-1750-2015-and-un-projection-until-2100?shown=Our%20World%20In%20Data%20-%20World%20Population%20over%2012000%20yearshttps://ourworldindata.org/grapher/world-population-1750-2015-and-un-projection-until-2100?shown=Our%20World%20In%20Data%20-%20World%20Population%20over%2012000%20years
World population has risen sharply “baby boom” • Global human population was <1 billion in 1800. • Population has doubled just since 1963. • We add 2.5 people every second (79 million/year).
United States birth rate (births per 1000 population) Baby boom 1946-1964 1939-1945 WWII 1909 1919 1929 1939 1949 1959 1969 1979 1989 1999 2009
Result of Large Populations pollution Greater need for resources starvation Reduction in biodiversity
Rates of growth vary from region to region At today’s 1.2% global growth rate, the population will double in 58 years
Factors Affecting Birth Rates and Total Fertility Rates • Children in Labor Force • Cost of raising and educating children • Availability of pension systems • Urbanization • Education and employment for women • Infant mortality rate • Average marrying age • Abortion • Availability of birth control
Is population growth really a problem? Population growth results from technology, medical care, sanitation, and food. Death rates drop, but not birth rates. Some people say growth is no problem. New resources will replace depleted ones. But some resources (i.e., biodiversity) are irreplaceable. Quality of life will suffer with unchecked growth. Less food, space, wealth per person
Demography studies human populations Demography: the application of population ecology to the study of human populations Population size Density and distribution Age structure, sex ratio Birth, death, immigration, and emigration rates
Population size and density Predictions of population size depend on different assumptions about fertility rates.
Age Pyramid United States 2016 • The United States’ “baby boom” is evident in age bracket 50–60. U.S. age structure will change as baby boomers grow older.
The demographic transition • Refers to the transition from high birth and death rates to low birth and death rates as a country develops from a pre-industrial to an industrialized economic system.
Demographic transition: Stages • The demographic transition consists of several stages: • Pre-industrial stage: high death rates and high birth rates • Transitional stage: death rates fall due to rising food production and better medical care. Birth rates remain high, so population surges. • Industrial stage: birth rates fall, as women are employed and as children become less economically useful in an urban setting. Population growth rate declines. • Post-industrial stage: birth and death rates remain low and stable; society enjoys fruits of industrialization without threat of runaway population growth.
Is the demographic transition universal? • It has occurred in Europe, U.S., Canada, Japan, and other nations over the past 200-300 years. • But it may or may not apply to all developing nations. • Failure in transition could occur in cultures… • That place greater value on childbirth or • Grant women fewer freedoms For people to attain the material standard of living of North Americans, we would need the natural resources of four and a half more Earths.
Empowering women reduces growth rates • More educated women have fewer children.
Population growth depends on various factors Birth Death Immigration Emigration Technological advances led to dramatic decline in human death rates. Widening the gap between birth rates and death rates resulting in population expansion