Human Populations Book, Principles of Environmental Science, Inquiry and Applications By Cunningham and Cunningham Presented by Doug Snyder
For every complex problem there is an answer that is clear, simple, and wrong. –H. L. Mencken
Is the World Overcrowded?
Views 1.We will exceed the carrying capacity of the planet 2.We will have more workers and smart people to solve our problems 3.We should have enough for everyone because it is only social justice problems that are causing some to be poor
History Population Explosion in the last 200 years. Today 7 Billion Global Human Population -grew fast recently 3 billion in 1960 to 6 billion in 1999 Maximum carrying capacity – probably 10-12 billion people – but suffering Malthus (1766-1834) - showed exponential growth with food shortages predicted
Karl Marx (1818-1883) - population growth results from poverty, resource depletion, pollution, social problems.
More Views on a Growing Population Technology increased the carrying capacity of the planet
But, food production has been based on cheap resources – production and transport Formula I=PAT, I= Impact, P=Population, A=Affluence, T=Technology Americans too much impact. 5 Planets! Ecological Footprint = land required to support a lifestyle (goods and services) P.79, What do you think? o Ethics o Intergenerational justice
Good for the economy? China.
o Economies of scale o Intelligent ingenious educated people o Larger consumer markets
What Makes Populations Grow? Demography: “…encompasses vital statistics about people, such as births, deaths, and where they live, as well as total population size.” 2 main categories of populations: o Young, poor, and growing o Old, rich, and shrinking
Conflict, economics, polities, and religion can keep contraceptive use low (Sub-Saharan Africa and Middle East) – ex. Chad and Congo, <10% use it Russia – economy down, pollution, hyperinflation, crime, corruption – death rates up, birth rates down and more birth defects. Africa – AIDS epidemic – 200 million person decline by 2050
Fertility Rates – Some definitions Fecundity = “…ability to reproduce.” Fertility = “…the actual production of offspring.” Crude Birth Rate = “…number of births in a year per thousand persons.”
Total Fertility Rate = “…the number of children born to an average woman in a population during her entire reproductive life.” – 12 or even 25 -30! Zero Population Growth (ZPG) = “…when births plus immigration in a population just equal deaths plus emigration.” – replacement rates from 2.1 to 5 or more. China’s One Child Policy – successful but abortions, infanticide, and abducted brides. boys to girls 140:100 in some regions
Mortality Offset Births and Life Expectancy Crude Death (Mortality) Rates = “…deaths per thousand persons in any given year.” Usually 4 to 20 per 1,000 Rising global population in last 300 years mostly due to declining mortality Life Expectancy = “…the average age that newborn infant can expect to attain in any given society.” Life Expectancy rose from 40 to 67.2 in the last 100 years due mostly to nutrition, sanitation, clean water, and education Disability Adjusted Life Years – accounts for premature death and loss of health Globally, above annual income $4,000 USD GNP, longevity flattens out , Fig. 4.8 Dependency Ratio – number of workers vs non-workers
Life Expectancy is Related to Income
Projection of Shifting Dependency Ratios
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Fertility and Culture Pronatalist Pressures – factors that cause people to want to have more children o Support for parents when parents are old o High infant mortality rates o Higher status in society o Income or work around the house o Cultures often value fertility o Male pride
In Low-tech Agricultural Areas Children are Additional Laborers
Fertility Rates by Country
Fertility and Culture Continued Education and Income Effects o Ed and freedom lead to women limiting fertility o Career and job opportunities o Money earned important o In developed countries, raising children is expensive
Demographic Transition Usually from high birth and death rates to low rates of both Fig. 4.13, Stages 1.Pre-modern 2.Urbanizing/industrializing 3.Mature/Industrial – high population growth here 4.Post Industrial
Death rates fall before birth rates do, so populations grow in stage 3
Stages of Demographic Transition
What stabilizes populations? 1.Growing prosperity and social reforms 2.Technology 3.Less developed nations can learn from other countries 4.Modern communication
Total Fertility Declines as Women’s Education Increases
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How to Complete the Transition Views View 1 - Focus on justice first (hunger, poverty, violence, environmental degradation, and overpopulation are usually the result of an unjust society)
o Ex. Kerala India, resources distributed fairly to all – success o If focus on population only, this leads to racism and hatred of the poor
View 2 – Focus on birth control
Andra Pradesh – incentives for sterilizations
Views from 1994 Conference on Population and Development
o Economic development, education, and empowerment of women, and health care needed o Must lower child mortality to lower birth rates o Increased income does not always equal benefits for children
Family Planning Parents control number and spacing of kids through rational decisions Birth control – anything (from celibacy and contraception to abortions)
What we do now affects the future Changes needed:
o Improved social, educational, and economic status for women o Improved status for children o Making decisions (calculated choice) o Social security and political stability (secure future) o Knowledge, availability, and use of birth control
Two Ways to Complete the Demographic Transition P. 88 • The Indian states of Kerala and Andra Pradesh exemplify two very different approaches to regulating population growth. • In Kerala, providing a fair share of social benefits to everyone is seen as the key to family planning. • The leaders of Andra Pradesh, on the other hand, have adopted a strategy of aggressively emphasizing birth control, rather than promoting social justice. • Both states have slowed population growth significantly. 4-28
World Population Projections
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