E.  Population

1.  Population growth dynamics

• Population growth has been slow through most of human history

• Accelerated in the last 200 years

• Particularly rapid in developing countries

Global population growth and projections, 1750 - 2100

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• Growth rate is declining, but annual increase in population is higher than 1950s - 1970s

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• Population growth will be most rapid in the poorest and most hard-pressed countries

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• Neo-Malthusian perspective - human population on a collision course with natural world, leading to catastrophic ecological consequences and an increase in the death rate

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2.  Predicting future growth

• Look at population age profile

• Population momentum - the tendency for a population to continue to grow, even if fertility rate drops to replacement level, as long as a high proportion of the population is in young age cohorts

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• Fertility rate - average number of live births per woman

• Replacement fertility level - fertility level that would result in a stable population (a little over 2 live births per woman)

• Fertility rate high in developing countries - Niger (7.6), Mali (6.4), Nigeria (5.7), Afghanistan (5.1), Iraq (4.6), Guatemala (3.3)

• Profiles can be affected by education

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3.  Demographic transition

• Death rates fall before birthrates as a society develops economically, leading population growth rates to first increase and eventually decrease

a.  Stage I - high birthrates and high death rates

• Large families, but poor healthcare cause children to die young

• Population stable

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b.  Stage II - death rates fall rapidly

• Industrialization leads to improved standard of living, public health, and medical care

• Families still large - children a source of support both in the present and in the future

• Population grows rapidly

• Could be okay in a country has resources and social institutions that can handle the population growth

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c.  Stage III - birthrates decline

• Changing social and cultural atmospere means smaller families seen as more desirable

• Part of change is that women are empowered => opportunity cost of childbearing is increased

• Starts with most educated part of society and then spreads

• Population growth rates decline

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d.  Stage IV - low birthrates and low death rates

• Continuation of Stage III

• Population stable

• Concern in some countries about the birthrate being too low => population will decline in the future

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4.  Population growth and economic growth

• What is the impact of population growth on economic growth?

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a.  Cobb-Douglas production function

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• Law of diminishing returns if capital is fixed and population grows

• Can be overcome if more capital is added (capital formation) and / or there is technological progress

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b.  Natural resource limitation

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c.  Negative economic impacts of population growth

(1)  Increased dependency ratios - high proportion of children not in workforce

(2)  Increase income inequality - increased supply of labor drives down wages, could lead to unemployment increasing

(3) Natural resource limitation - leads to diminishing returns

(4)  Market failure - common resource leads to overuse, as does not factoring in negative externalities

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5.  Ecological perspective

• Standard economics assumes no limit on population or output growth

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a.  Carrying capacity

• The level of population and consumption that can be sustained by the available natural resource base

• Ecological approach views growth is limited by the carrying capacity

• Humans have been able to expand carrying capacity - fertilizers, fossil fuel and nuclear energy

• Significant ecological cost to expanding carrying capacity, which could ultimately reduce it:

(1)  Climate change

(2)  Buildup of long-lived toxic waste

(3)  Erosion and degradation of topsoil

(4)  Overuse and pollution of fresh water supplies, including depletion of aquifers

(5)  Loss of biodiversity

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b.  Impact of population, affluence, and technology

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• Population, affluence, and technology could be related to one another instead of being independent

• Unequal distribution of consumption throughout the world => some focus should be on inequality

• As development occurs, per capita demand on resources and pollution will result

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6.  Population policies

• Compulsory government population control has been attempted

Ex. - One child policy in China

• Link between high fertility and poverty => dealing with poverty could have a side benefit in dealing with population

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a.  Policies

(1)  Promotion of education and other social programs

(2)  Improvement in the status of women

(3)  Improved nutrition and health care, including contraception

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b.  Impact on urban areas

• Major social and infrastructure problems

(1)  Inadequate housing and sanitation

(2)  Congestion

(3)  Air and water pollution

(4)  Deforestation

(5)  Solid waste problems

(6)  Soil contamination

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