Human Population Growth; Past, Present, and Future

1. Human Population Growth; Past, Present, and Future Applying the principles of population dynamics and sustainability to the growth of the human population

2. World’s 10 Most Populated Countries

3. Population projections For the next 20 years

4. Population Growth by Continents

5. Current Population Trends • World population = 7.35 billion (6,400,000) in 2017 • More than doubled since 1963 = 3.2 billion • In 2050 could be 9 – 10.6 billion • Amplifies all environmental problems • Largest increase expected in developing countries (approximately 97%) • Decreasing in some developed countries • Rate actually decreased between 1963-2004, but the population has still doubled from 3.2 –6.4 billion

6. Factors Affecting Human Population Size Population change equation Population change = (Births + Immigration) – (Deaths + Emigration) Crude birth rate = births per 1000 people in population per year Crude death rate = deaths per 1000 people in population per year

7. Total Fertility Rate(TFR) - Number of children a woman has during her lifetime, averaged for population. • same as biotic potential (r) • Replacement Level Fertility - Number of children needed to replace everyone in the population. • Varies between regions • 2.1 with low infant mortality • 2.5 with high infant mortality • Zero Population Growth - Birth rate equals death rate.

8. Sex Ratio - Age Distribution • Sex Ratio- Relative number of males and females in a population • Age Distribution - Number of individuals of each age in a population • Together they tell how a population will grow

9. Population Age Structure Developing Countries Developed Countries Growth is determined by teenagers – the population wave of the future. 30% of pop’n <15 years = 1.9 billion more into reproductive years.

10. Developed Countries Low infant mortality rate Life expectancy 77 years Total fertility rate = 2.0 21% population <15 12% population >65 Per capita GDP = $36,110 Developing Countries High infant mortality rate Life expectancy 52 years Total fertility rate = 5.7 44% population <15 3% population >65 Per capita GDP = $800 Population Trend Comparisons

11. Human Population Issue • Several factors determine the impact of a society on natural resources. • Population size • Population density • Degree of technological development • Demography - Study of populations and their characteristics. • Larger ecological footprint in U.S. than in developing countries. Why?

12. Factors Affecting Birth Rates and Total Fertility Rates • Children in Labor Force • Cost of raising and educating children • Availability of pension systems • Urbanization • Education and employment for women • Infant mortality rate • Average marrying age • Abortion • Availability of birth control

13. Major social factor determining family size is the role of women in society. • Early marriages foster high fertility rates. • Lack of education opportunities for women reduces their options. • When level of education increases, fertility rates fall. • The most important factor is the ability of women to control the size of their family. • Access to birth control is key.

15. United States Population Picture • US population has a post-war baby boom period, significantly affecting pop. trends. • 20 yr period following WWII • By 2030, 20% of US pop will be over 65

16. Demographic Transition As countries become industrialized, death rates, then birth rates decline.

17. Overpopulation Concerns

18. Global Megacities Number of large cities growing. World’s urban population will increase from 3.1 billion to 5 billion from 2004-2030.

19. US metropolitan areas

20. Undesirable Impacts of Urban Sprawl

21. Loss of crop land, forest land, and wetlands

22. Fragmenting fish and wildlife habitats

23. Increased impervious surfaces means more flooding

24. And soil erosion

25. Environmental Impact

26. Growth Management Act1990 • The GMA requires state and local governments to manage Washington’s growth by identifying and protecting critical areas and natural resource lands, designating urban growth areas, preparing comprehensive plans and implementing them through capital investments and development regulations. • GMA is passed to help protect areas critical for natural resources by concentrating growth in urban areas

27. And a larger ecological footprint

28. Cutting Global Population Growth • Family planning • Improve health care • Elevate the status of women • Increase education • Involve men in parenting • Reduce poverty • Sustainability

29. Population Control • SMALL GROUP ACTIVITY-- • Debate: Should abortion be used as a means to control population growth? Why or why not? Explain your answer in a one page essay. Use research to quote sources and argue your point of view on this subject.

30. Review Questions • What are the world’s ten most populated countries? • For the year 2025, what are the population projections for China, India, and the USA? • Which continent will experience the largest population growth? Which continent will experience the least growth? • As of 2017, what is the population of the whole world? • What are some factors that affect population growth?

31. Review Questions (continued) 6. What is sex ratio? 7. What is age distribution? 8. What are some countries that have rapid population growth? What are some countries that have slow population growth? 9. What is the major social factor determining family size? • What are three factors that determine the impact of a society on natural resources? • List nine factors that affect birth rates and total fertility rates.

32. Review Questions (continued) • What are five social factors determining family size in society? • By the year 2030, how much of the U.S. population will be over 65 years old? • What is demography? • Name five of the world’s Megacities. • How much will the world’s urban population increase from 2004 to 2030? • What is the Growth Management Act of 1990? • What are some ways to cut global population growth?