environmental history chapter 2. early history earth has existed for an estimated 4.6 billion years...
TRANSCRIPT
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- Environmental History Chapter 2
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- Early history Earth has existed for an estimated 4.6 billion years Homo sapiens have been on earth only about 60,000 years Until about 12,000 years ago men were mostly hunter-gatherers.
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- Major Cultural Changes Agricultural revolution Industrial revolution Information and globalization revolution
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- Hunter-gatherers Survived by eating edible wild plants, fishing, hunting, and scavenging meat killed by other animals Lived in small bands Were nomads They discovered: Which plants and animals could be eaten and used as medicine Where to find water How plant availability changed throughout the year How game animals migrated
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- Advanced hunter gatherers Used more advanced tools and fire Contributed to the extinction of some animals (saber-toothed tiger) Altered distribution of plants by carrying seeds OVERALL IMPACT ON THE ENVIRONMENT WAS LOW DUE TO: Small population Low resource use/person Migration allowed ecosystem to repair itself Lack of technology
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- Agricultural revolution 10,000-12,000 years ago Also called Neolithic revolution Gradual shift from nomads to settling in agricultural communities Domesticated animals and cultivated wild plants
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- Slash-and- burn cultivation Clear forest (mainly in the tropics) Burn vegetation and underbrush This adds nutrients to the soil which is often nutrient poor Led to Shifting cultivation
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- 3 Harvesting for 2 to 5 years 1 Clearing and burning vegetation 2 Planting 4 Allowing to revegetate 10 to 30 years
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- Most early farmers practiced SUSTAINABLE CULTIVATION Had little impact on the environment because: Depended on human muscle power and crude tools Low population size and density Land was available for movement to other areas
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- The Industrial Revolution
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- Began in England Based on dependence on coal (nonrenewable fossil fuel) rather than renewable wood Invention of the steam engine Switched from small-scale localized production to large-scale production of machine-made goods. Movement from rural to cities Often very bad living and working conditions
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- Resulted in: Fossil-fuel powered farm machinery New plant-breeding techniques increasing yield per acre More reliable food supply Longer life spans Increase in population size
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- Information and Globalization Revolution Many new technologies telephone, computers, tv, etc Automated data bases Remote sensing satellites
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- Positively Helps us understand earth, economics, etc. Allows use of remote sensing satellites Enables use to develop computer models Can reduce pollution and environmental degredation Negatively: Information overload Confusion and a sense of hopelessness Increases environmental degradation and decrease in cultural diversity
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- History of United States Tribal Era Occupied by indigenous people, called Indians now called Native Americans Had a fairly low environmental impact
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- Frontier Era (1607-1890) Began with European colonists settling North America Had a FRONTEIR ENVIRONMENTAL WORLDVIEW The wilderness was there to be conquered and cleared. Kill the dangerous animals and Native Americans
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- Conservation Era (1870-1930) Concern over resource use; Federal governments responsibility to protect public lands. (Forest Reserve Act 1891) Public health initiatives Environmental restoration projects
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- Important Figures of the Conservation Era Henry David Thoreau John Muir Theodore Roosevelt Alice Hamilton Franklin Roosevelt
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- Environmental Era (1960 -2000) The environmental movement The science of ecology Spaceship Earth worldview: caretakers of the planet 1980s:anti-environmental movement 1990s: environmental awareness
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- Important Figures in Environmental Era Rachel Carson (Silent Spring 1962) Richard Nixon: EPA, ESA Jimmy Carter: DOE, Superfund Ronald Reagan: anti-env. Bill Clinton: env. concerns a priority George W. Bush: drilling in ANWAR Barack Obama: few laws, okd offshore drilling in VA.