Sustainability Impacts and Consequences

Lecture Outlines

Chapter 8 Environment: The Science behind the Stories 4th Edition Withgott/Brennan

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This lecture will help you understand:

• Human population growth • Different viewpoints on this growth • Population, affluence, and technology’s effects • Demography • Demographic transition • Factors affecting population growth • The HIV/AIDS epidemic • Population and sustainable development

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Case study: China’s one-child policy

• In 1970, China’s 790 million people faced starvation • The government instituted a one-child policy - The growth rate plummeted - The policy is now less strict • The successful program has unintended consequences: - Killing of female infants - Black-market trade in teenage girls

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Our world at seven billion

• Populations continue to rise in most countries - Particularly in poverty-stricken developing nations • Although the rate of growth is slowing, we are still increasing in numbers

It would take 30 years, counting once each second, to count to a billion! It would take 210 years to count to 7 billion!

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The human population is growing rapidly

• Our population grows by over 80 million each year • It took until 1800 to reach 1 billion • In 1930 (130 years later) we reached 2 billion • We added the most recent billion in 12 years

Due to exponential growth, even if the growth rate remains steady, population will continue to grow

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Rates of growth vary from region to region

• At today’s 1.2% global growth rate, the population will double in 58 years (70/1.2 = 58) • If China’s rate had continued at 2.8%, it would have had 2 billion people in 2004

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Is population growth a problem?

• Technology, sanitation, medication, and increased food increase population - Death rates drop, but not birth rates • Population growth was seen...