Population boom
• falling death rates and longer lives from better nutrition, sanitary conditions, and healthcare
Demographic Transition
• After initial population explosion, birth rates drop in more urban affluent societies
Population policy
• “development = population control”• family planning programs• US retreating under Bush—abstinence only
• female literacy/education• China’s experiment• 1979 one-child policy• 250 million fewer births• a success?
Problems of population slowing
• growth of dependent portion of population• will be especially acute in developing world• It took 50 ys for US average age to increase 5 ys—
Mexico’s will go up 20.
Problems of population growth
• polluting and exhausting resources• Example: Rwanda
• is the problem population, or unsustainable practices?
• example--eating higher on the food chain
water• US water used for glass of milk, burger, small
steak?• 200 gallons• 800 gallons• 1300 gallons
• depleting aquifers, falling production
Soil degradation and desertification
• “New Lands”--Aral Sea• Local life expectancy from 65 to 51• Highest rate of cancer of esophagus in world• http://www.films.com/id/12468/Killing_the_Aral_Sea_Catastrophe_by_Design.htm
Rainforest destruction
• From logging, slash and burn, fuel wood, cash crops, and ranching
• http://www.voanews.com/english/2006-06-09-voa48.cfm
Soil erosion
• 99% of world’s food from soil, but losing soil—25 m. acres per year
• from slash and burn and unsustainable farming, logging, and grazing
• Lost to water, wind
Some Solutions
• Technology• Green Revolution?• Problems: needs expensive inputs, and more water• GM?
A special case: the sea• problems of stewardship of a collective
good• the failure of international agreements to
protect fisheries• 1995 wild fish harvest peaked, despite more
intensive fishing• Aquaculture fastest growing animal
husbandry
Consequences- raising sea levels, causing droughts and storms, and
disrupting ecosystems, crop productivity, ocean acidification
- self-sustaining processes:- melting polar ice-caps cool less and reflect less light/heat- thawing permafrost releases more g.h. gasses
Kyoto
• 1997 Kyoto Protocols, formally in effect since 2004
- U.S. and other developed countries were to reduce g.h. gasses below 1990 levels by 2012
• 1997-’01 Senate fails to ratify the treaty• 2001 Bush dismisses Kyoto Protocols• cites insufficient evidence, too great costs• Developing countries, like China and India exempted
What can be done?
• Gas tax• cleaner and alternative forms of energy• California’s “Pavley Law”, and beyond• Northeast states’ cap and trade• Ethanol—and Brazil’s cellulosic ethanol• nuclear?
• carbon sequestration
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