1. Environmental Problems and Their Causes
Population, Resources, Environmental Degradation, and Pollution

2. What is The “Environment”?
Environment - all external conditions and factors (living and non-living) that affects all organisms

3. What is The “Environment”?
Two Major Components of the Environment
Biotic - living organisms
Abiotic - non-living (chemicals, energy)

4. What is “Environmental Science”?
Environmental Science - the study of how we and other species interact with one another and with the abiotic environment of matter and energy

5. Sustainable Living All life on earth depends on two forms of capital:
Solar Capital - energy from sun
Earth Capital - air, water, soil wildlife, minerals, natural recycling

6. Sustainable Living
The “Environment” is comprised of solar and earth capital
Sustainability - the ability of a system to survive for some specified (finite) time

7. Sustainable Living
Sustainable Society - a society that manages its economy and population size without depleting earth capital and thereby jeopardizing the prospects of current and future generations of humans and other species

8. Sustainable Living
Sustainable Living - living off the income without depleting the capital that supplies the income
$1 million 10% annual interest = $100,000 annual income

9. Growth and Wealth Gap
Linear (Arithmetic) Growth - growth in which a quantity increases by a constant amount per unit of time
Example: an automobile accelerates by 1 mph every second

10. Growth and Wealth Gap
Exponential (Geometric) Growth - growth in which a quantity increases by a fixed percentage of the whole per unit of time
Example: an automobile doubles its speed very second (1, 2, 4, 8, 16, …)

11. Growth and Wealth Gap 2n where n = time
Formula for Exponential (Geometric) Growth 2n
where n = time

12. Doubling Time = 70 ÷ percentage growth rate
Growth and Wealth Gap
Doubling Time - the time it takes for a quantity growing exponentially to double
Rule of 70
Doubling Time = 70 ÷ percentage growth rate

13. Growth and Wealth Gap Example of Doubling Time
Annual global population growth rate = 1.47%
70/1.47 = 48 years
Population will double in 48 years

14. Growth and Wealth Gap Human Population Growth
Global Population Time (yrs)
1 billion 1 million
2 billion
3 billion 30
4 billion 15
5 billion 12

15. Growth and Wealth Gap
Environmental Impacts of Exponential Human Population Growth
73% of the habitable area of the earth has been altered by human activities

16. Growth and Wealth Gap Economic Growth
An increase in the ability of an economy to provide goods and services
The increase in the real value of all final goods and services produced by an economy

17. Growth and Wealth Gap
Gross National Product - market value in current dollars of all goods and services produced by an economy for final use during a year
Increasing GNP indicates economic growth

18. Growth and Wealth Gap
Economic growth achieved by increasing throughput of matter and energy resources used to produced goods and services
Increased throughput achieved through population growth and/or increased consumption per person

19. Growth and Wealth Gap Per Capita GNP - GNP divided by total population
United Nations Classification of World’s Countries
Developed (MDCs)
Developing (LDCs)

20. Growth and Wealth Gap MDCs 20% world’s population
Highly industrialized
High per capita GNP (>$4,000)
85% of world’s wealth
Consume 88% of world’s natural resources

21. Growth and Wealth Gap MDCs Generate 75% of world’s pollution
U.S., Germany, Japan account for > 50% of world’s economic output

22. Growth and Wealth Gap LDCs 80% world’s population
Low to moderately industrialized
Low to moderate per capita GNP
15 to 20% of world’s wealth
Consume 12% of world’s natural resources

23. Growth and Wealth Gap LDCs Account for 9 of every 10 babies born
Account for 98% of all infant and childhood deaths
1 million people added every 4 days
35% of population is under age 15

24. Growth and Wealth Gap
Development - change from a society that is rural, agricultural, illiterate, and poor with a rapidly growing urban population to one that is mostly urban, industrial, educated, and wealthy

25. Growth and Wealth Gap The Wealth Gap Widening gap since 1960
Environmental Impacts
High population growth rates
Widespread urbanization
Resource depletion
Famine (~20 million people annually)

26. Resources and Environmental Degradation
Resource - anything we get from our environment to meet our needs and wants
Classification of Resources
Renewable
Potentially Renewable
Nonrenewable

27. Resources and Environmental Degradation
Renewable Resource - a resource that is virtually inexhaustible on a human time scale

28. Resources and Environmental Degradation
Potentially Renewable Resource - a resource that can be replenished fairly rapidly (hours to decades) through natural processes
Sustainable Yield - the highest rate at which a potentially renewable resource can be used without reducing its available supply

29. Resources and Environmental Degradation
Potentially Renewable Resource - a resource that can be replenished fairly rapidly (hours to decades) through natural processes
Environmental Degradation - depletion or destruction of a potentially renewable resource by using it faster than it is naturally replenished

30. Sustainable Yield
The Sustainable Yield “Teeter-Totter”
Use
Renewal

31. Environmental Degradation
Use
Renewal

32. Resources and Environmental Degradation
Nonrenewable Resource - a resource that exists in a fixed amount in various places in the earth’s crust and has the potential for renewal only by geological, physical, and chemical processes taking place over hundreds of millions to billions of years

33. Resources and Environmental Degradation
Nonrenewable Resource
Economical Depletion - occurs when the cost of exploiting the resource exceeds it economic value

34. Resources and Environmental Degradation
Nonrenewable Resource
Options to deal with economical depletion
Recycling
Reuse
Waste less
Use less
Develop a substitute

35. Resources and Environmental Degradation
Nonrenewable Resource
Recycling - collecting and processing a resource into new products
Reuse - using a resource over and over in the same form

36. Pollution
Pollution - an undesirable change in the characteristics of air, water, soil, food that can adversely affect health, survival, and activities of living organisms

37. Pollution
Sources of Pollution
Point Sources
Non-point Sources

38. Pollution Factors Determining the Harmfulness of Pollutants
Chemical Nature
Concentration
Persistence

39. Pollution Solutions to Pollution Input Pollution Control
Pollution prevention strategy based on:
Reduce
Reuse
Recycle

40. Pollution Solutions to Pollution Output Pollution Control
Pollution cleanup strategy
Problems:
Often a temporary bandage
Removes pollutant from one area and transfers it to another area
Often too expensive to reduce pollutants to acceptable levels