1 / 41

Decoding Earth's Carrying Capacity: The Human Population Puzzle

Explore the factors and impacts of human population growth, fertility rates, and demographic transitions. Learn about family planning, migration, and the global population's future. Dive into discussions on life expectancy, age structure, and sustainable development. Unravel the complexities of Earth's carrying capacity through data, theories, and real-world examples.

cmessina
Download Presentation

Decoding Earth's Carrying Capacity: The Human Population Puzzle

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 7 The Human Population

  2. Scientists Disagree on Earth’s Carrying Capacity Figure 7.1

  3. Scientists Disagree on Earth’s Carrying Capacity • The following graphs show theoretical models of food supply and population size.

  4. 1. The current world population is closest to which of the following? a. 1 million b. 500 million c. 1 billion d. 7 billion e. 20 billion

  5. Factors that Drive Human Population Growth • Demography- the study of human populations and population trends. • Changes in Population Size • Fertility • Life Expectancy • Age Structure • Migration

  6. Changes in Population Size • Immigration- the movement of people into a country • Emigration- the movement of people out of a country. • Net migration rate- the difference between immigration and emigration in a give year per 1,000 people in the country.

  7. Changes in Population Size • Crude birth rate (CBR)= the number of births per 1,000 individuals per year. • Crude death rate (CDR)= the number of deaths per 1,000 individuals per year. • Global population growth rate = (CBR- CDR)/ 10 • National population growth rate = (CBR+ immigration) - (CDR + emigration)/ 10 • Doubling time (in years)= 70/growth rate

  8. Crude Birth Rates Compared • >30- considered high • < 18- considered low • Global = 20 • Germany = 8 • Niger =50 • US= 14

  9. Fertility • Total fertility rate- an estimate of the average number of children that each woman in a population will bear. • Replacement level fertility- the total fertility rate required to offset the average number of deaths in a population and for the current population size to remain stable.

  10. Fertility • Developed countries- countries with relatively high levels of industrialization and income. • Developing countries- countries with relatively low levels of industrialization and income of less that $3 per person per day.

  11. Female education and TFR • Female literacy and school enrollment are correlated with total fertility rate. • More-educated women have fewer children.

  12. 2. RLF for a couple is • 1.0 • 2.0 • 2.1 • 3.0 • Varies depending on country

  13. Life Expectancy • Life expectancy- the average number of years that an infant born in a particular year in a particular country can be expected to live, given the current average life span and death rate of that country.

  14. Life Expectancy • Infant mortality rate- the number of deaths of children under 1 year of age per 1,000 live births. • Child mortality rate- the number of deaths of children under age 5 per 1,000 live births.

  15. Age Structure • Age structure diagrams (population pyramids)- visual representations of age structure within a country for males and females.

  16. Migration • High migration rates can also cause a country to grow. • US: 3.3/ 1000 • Figi: -8/ 1000

  17. 3: Which country is undergoing rapid population growth? C B A

  18. The Demographic Transition • The theory of the demographic transition is the theory that as a country moves from a subsistence economy to industrialization and increased affluence, it undergoes a predictable shift in population growth.

  19. The Stages of the Demographic Transition • Phase 1(Pre-Industrial): Slow population growth because there are high birth rates and high death rates which offset each other. • Phase 2(Transitional): Rapid population growth because birth rates remain high but death rates decline due to better sanitation, clean drinking water, increased access to food and goods, and access to health care. • Phase 3 (Industrial): Stable population growth as the economy and educational system improves and people have fewer children. • Phase 4 (Post- Industrial): Declining population growth because the relatively high level of affluence and economic develop encourage women to delay having children.

  20. 4. 5.

  21. 6. Using the demographic transition model, which stage would be characteristic of death rates falling while birth rates remain high? • Pre-industrial • Industrial • Post-industrial • Transitional • None of the above

  22. 7: In a human population undergoing the demographic transition, which of the following generally decreases first? Birth rate Death rate Avg. family size Life expectancy Level of education

  23. Family Planning • Family planning- the regulation of the number or spacing of offspring through the use of birth control.

  24. What Is Family Planning? Definition Measures (tools) enabling parents to control the number of children they have (if they so desire) Goals of Family Planning Not to limit births For couples to have healthy children For couples to be able to care for their children For couples to have the number of children that they want

  25. Population Momentum • A population will continue to grow for a period of time after efforts to reduce birth rates because there will still be high numbers of women in their reproductive years.

  26. The 12 Most Populous Countries in the World

  27. The relationship between economic development and population growth rate for developing nations.

  28. 8. The number of children an average woman would have, assuming that she lives her full reproductive lifetime, is known as the – a. Birth rate b. Crude birth rate c. TFR d. RLF e. Zero population growth

  29. Ecological Footprints • Affluence - having a lot of wealth such as money, goods, or property.

  30. 9. The average American’s ecological footprint is approximately • The size of a shoe • 0.5 acres • 3 acres • 5 acres • 9 acres

  31. The IPAT Equation • To estimate the impact of human lifestyles on Earth we can use the IPAT equation: • Impact= Population X Affluence X Technology

  32. The wealth gap • Residents of developed nations have larger houses, more possessions, and more money than residents of developing nations. • The richest 20% of the world’s people consumes 86% of its resources, and has > 80 times the income of the poorest 20%.

  33. Three Most Populous Countries • China- 1.3 Billion • India- 1.2 Billion • Positioned to surpass China by 2030 • More people living in India than the entire western hemisphere • US- 300 Million

  34. The Impact of Affluence • Gross domestic product (GDP)- the value of all products and services produced in a year in that country. • GDP is made up of consumer spending, investments, government spending, and exports minus imports. • A countries GDP often correlates with its pollution levels.

  35. 10. Which of the following would most likely have the greatest positive impact on the quality of the natural environment worldwide? • Discovery of new reserves of fossil fuel in coastal areas • Increased agricultural production on marginal desert lands • Increased life expectancy in more developed nations • Increased reliance on food from ocean ecosystems • Stabilization or reduction of the size of the human population

  36. 11. Which of the following factors is associated with the highest potential for population growth? • High percentage of people under age 18 • High percentage of people in their 30’s • High percentage of people in their 50’s • High percentage of people in high-income groups • High percentage of people in low-income groups

More Related