1. Chapter 7
The Human Population

2. The Environmental Implications of China’s Growing Population
Human population size, affluence and resource consumption
Example – China
Current population estimate: 1.35 billion
What has China done?  One Child Policy
CONTROVERSIAL!!
Successful in reducing fertility rate
As China’s standard of living improves…

3. Human Population
Exponential growth and limiting factors

4. Scientists Disagree on Earth’s Carrying Capacity
Thomas Malthus
Concluded?
What is carrying capacity of humans?
Graphs show theoretical models of food supply and population size

5. Projecting Future Populations
Population clock:
Population is increasing
Growth rate (r) has started to decline
Projections for 2050
Low = 7.7 billion
High = 10.6 billion
Most likely = 9.1 billion

6. 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

7. Changes in Population Size
Factors that increase a population:
Factors that decrease a population:
If inputs are greater than outputs, population goes up
In human history

8. Changes in Population Size
Let’s look at immigration and emigration first…
Difference…
Net migration rate – be able to calculate!!
Positive net migration vs. Negative net migration
Important to still look at where they are going

9. Changes in Population Size
Crude birth rate (CBR)
Crude death rate (CDR)
Some important formulas:
Global population growth rate = (CBR- CDR)/ 10
National population growth rate = [(CBR+ immigration) - (CDR + emigration)] / 10
Doubling time (in years) = 70/ growth rate

10. Fertility ~ Terminology
Total fertility rate (TFR)- 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

11. Fertility and HDC vs. LDC
Developed countries- countries with relatively high levels of industrialization and income
Replacement level fertility?
Developing countries- countries with relatively low levels of industrialization

12. Fertility ~ TFR Influences
Major influences on total fertility rate
Cultural traditions
Social & economic status of women
Education of women
Family planning
Government Policies

13. Fertility ~ TFR Influences Cultural Traditions
Culture influences and controls individuals’ behaviors
Gender- important part of culture
Marriage age
Family size expectations
High infant and child mortality rates
Children often work in family business (gender)
Religious values

14. Fertility ~ TFR Influences Social & Economic Status of Women
Gender inequality is common worldwide  lead to higher TFR
Disparities
Political participation
Education
Social status
Economic status
Legal rights
Employment and earnings

15. Fertility ~ TFR Influences Education
Link between education and TFR.. Why?
Control of fertility
Women with more education
Marry later
Have fewer children
Spouse as partner

16. Fertility ~ TFR Influences Family Planning
Family planning- the regulation of the number or spacing of offspring through the use of birth control
Focus on maternal and child health
Difficulties - Gender inequality and cultural constraints
Examples of family planning campaigns:
Kenya
Thailand

17. Fertility ~ TFR Influences Government Policies and Fertility
Government involvement includes:
Determine the minimum age people may marry
Amount of compulsory education
Budgets for family planning services, education, health care, old-age security, incentives for smaller or larger family size
Tax structure- additional charges or allowances based on family size
78 developing countries have recognized they must limit population growth in recent years
Most common example – CHINA
India, Nigeria, Europe

18. 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
Resource consumption?
Reported in 3 ways:
Overall population
Males only
Females only

19. Life Expectancy - Factors
Infant mortality rate
Child mortality rate
IMR and CMR may be drastically different for a portion of a population

20. Life Expectancy – Factors
CDR and life expectancy not directly linked
When you have a higher number of elderly in a population, CDR is higher
Disease helps to regulation human population
In the past – TB and malaria were biggest threats
Now – HIV

21. Age Structure
Age structure diagrams- visual representations of age structure within a country for males and females
Aka: population pyramids
Generalized:

23. Age Structure
Population momentum – continued population growth that does not slow in response to growth reduction measures

24. The Demographic Transition
Theory of the demographic transition - as a country moves from a subsistence economy to industrialization and increased affluence, it undergoes a predictable shift in population growth
Does not adequately describe population growth patterns
Industrial activity does not link to population size

25. The Demographic Transition

26. The 12 Most Populous Countries in the World

27. Economic Development
Population disparity between rich and poor counties has accelerated in recent decades

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

29. The IPAT Equation
IPAT – estimates the impact of human lifestyles on Earth
Conceptual representation
Formula: I = PAT
I – environmental impact
P – population
A – affluence
T – technology
Some use “destructive technology” instead of technology

30. Local, Global and Urban Impacts
Impacts can occur on multiple scales (region/city, country, global)
Local impacts:
Can lead to overuse or resources and environmental degradation
Global impacts:
Examples: reduction in atmospheric CO2 uptake

31. Urban Impacts
Urban area – one that contains more than 1000 people per square mile
More than 75% of people in developed countries
Challenges to environment

33. The Impact of Affluence
Gross domestic product (GDP) - the value of all products and services produced in a year in that country
Made up of consumer spending, investments, government spending, and exports minus imports
Country’s GDP and pollution levels
Why is this important?  best way to save environment:
Rising income = falling birth rates
Can afford environmental improvements / increased efficiency of resources

34. Sustainable Development is a common, if elusive goal
Many people believe we cannot have both economic development and environmental protection
So how can sustainable development be achieved?
Millennium Ecosystem Assessment project (2005) – global analysis of effects of human population on ecosystem services (clean water, forest products, natural resources) and offer a blueprint for sustainable development
Conclusions…