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  • Please examine the world map of wealth and poverty. What are some examples of relatively

  • wealthy nations across our globe? On the other hand, where are poorest nations located? Now

  • that you have established the pattern of wealth and poverty on our planet, take a look at

  • population growth rates. By comparing the two maps, identify the relationship between

  • population growth and wealth. Is there a relationship?

  • Growth rates are usually higher in poorer nations due to a variety of factors. The most

  • significant of which is that many of the poorer nations rely on agriculture for survival.

  • Agrarian, or agricultural based, societies need more laborers to work the fields and

  • therefore families typically have more children. On the other hand, wealthier societies typically

  • have lower birth rates since children aren't necessary for basic survival.

  • There are many more people in the developing world, but the level of impact per person

  • is relatively low. However, in the developed world, population growth is low, but due to

  • their relative wealth, each person's affect on the environment is much more substantial.

  • As this illustration demonstrates, there is a major difference in how developing and developed

  • countries affect our environment. As you can see, developing and developed nations both

  • put a strain on our environment's ability to sustain life, just in different ways.

  • The actual number of people on our planet is also a major concern. Take a look at how

  • population has grown over time:

  • Notice that after the Agricultural Revolution, population began to increase. It took almost

  • 10,000 years for the population to reach one billion, then only 130 years to double to

  • two billion, but it took only 45 years to double again to four billion. So at today's

  • doubling rate, it will only take 54 years for us to once again double the world's population.

  • -- that would be 13 billion people on our planet. Now let's think: Can we sustain that

  • number? Are we doing a great job of sustaining the 6.5 billion we have today? We will discuss

  • this further in class where I'll introduce the Malthusian theory.

  • A population pyramid, or an age structure diagram, is a chart that describes population

  • by age and gender. These diagrams usually describe the population of a nation; however,

  • this one combines all Less Developed Countries on the left and the More Developed Countries

  • on the right. Please note the different structure of the diagrams. First, let's examine the

  • diagram for the Lesser Developed Countries. Notice there are far more people in their

  • adolescent years than in their elderly years. Why do you think this might be the case? Think

  • about the factors that lead to birth and death rates within the Less Developed Countries.

  • Now examine the diagram for the More Developed Countries and ask the same questions.

Please examine the world map of wealth and poverty. What are some examples of relatively


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B1 中級

地理。人口 (Geography: Population)

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    黃駿祐 發佈於 2021 年 01 月 14 日