1. Chapter 1: Key Themes in Environmental Sciences

2. Major Themes of Environmental Science
Our population has more than doubled in the last 40 years
6.8 billion people alive today
Continuing on this trend would lead to 9.4 billion by 2050
How many people can the Earth sustain?
Depends on science and value
Also question of people and nature

3. Human Population Growth
John Eli Miller Family
Example of family population explosion

5. Human Population Growth
Miller family emphasizes a major factor in modern population explosion
Modern technology
Modern medicine
Supply of food, clothing and shelter
All decrease the death rate and increase net growth rate

6. Population changes since 1950 and projected to the year2150.

7. Our Rapid Population Growth
Human population growth is the underlying issue of the environment.
Damage is directly or indirectly due to pop inc

8. Famine and Food Crisis
Famine occurs when human pop exceeds its environmental resources
Sahel region of Africa in 1970s
½ million people starved to death
Millions affected by malnutrition
Emerging global food crisis
Due to rise in fuel cost = higher food cost

9. Famine and Food Crisis

10. Food Crisis

11. Sustainability and Carrying Capacity
What is the maximum number of people the Earth can sustain?
Much of this book will help answer that ?
Currently we are using resources unsustainably.
Faster that they can be replenished.

12. Sustainability: The Environmental Objective
Is Earth very survival really in danger?
Earth will go on w/o us
Quality of human enviro at risk

13. Sustainability
Sustainability refers to resources and their environment.
Sustainable resource harvest
Same quantity of that resource can be harvested each year for an unlimited amount of time.
Sustainable ecosystem
An ecosystem from which we are harvesting a resource that is still able to maintain its essential functions/properties.

14. Sustainability Two points to understanding sustainability
Sustainability means for an unspecified long period of time.
Sustainable growth is an oxymoron.

15. Sustainable Global Economy
Population of humans living in harmony w/ natural support systems.
An energy policy that does not pollute, cause climate change or present unacceptable risk.
A plan for renewable resources that will not deplete the resources or damage ecosystems.

16. Sustainable Global Economy
A plan for nonrenewable resources that does not damage region or global environ.
And provides a share for future generations
A social, legal, and political system that is dedicated to sustainability.

17. Sustainable Global Economy
To achieve we must
Develop an effective population-control strategy.
Completely restructure our energy programs.
Institute economic planning that will encourage pop control and wise use of resources.
Implement social, legal, political and eductional change.

18. Moving Toward Sustainability
The new paradigm
Evolutionary rather than revolutionary.
Inclusive, not exclusive.
Proactive, not reactive.
Attracting, not attacking.
Assisting the disadvantage, not taking advantage.

19. Carrying Capacity of the Earth
Defined as
the maximum number of ind of a species that can be sustained by an environment
w/o decreasing the capacity of the environ to sustain that same amount in the future

20. A Global Perspective
The actions of many groups of people at many locations affects the environment of the entire world.
Gaia hypothesis
James Lovelock and Lynn Margulis
Life affects the environment at a global level

21. An Urban World We are becoming an urban species In developed countries
75% live in urban area
Developing countries
40%

22. An Urban World Megacity
Urban area with at least 10 million inhabitants

23. People and Nature We depend on nature directly for
Wood
Water
Air
And indirectly for “public services functions”
E.g. soil formation

24. Soil Fertility and Structure

25. People and Nature
People and animals alter and change their environment.
Dichotomy of 20th century is giving way.
New unity
Sustainable environ and economy compatible.

26. Science and Values We must choose what we want the environment to be
Value judgment regarding the world’s human population problem
Choice between desire to have large family and the need to limit the human population.
The more high tech and powerful our civilization, the more knowledge is required.

27. Fishing for Salmon

28. Precautionary Principle
Rio Earth Summit on Sustainable Development
Defined PP – when there is a great threat of serious environ damage we should not wait for scientific proof before taking precautionary steps to prevent potential harm.

29. Precautionary Principle
PP is a proactive, rather than a reactive, tool.
Adopted by the city of SF and the European Union

30. Placing a Value on the Environment
The value of the environment based on 8 justifications
Utilitarian
Ecological
Aesthetic
Recreational
Inspirational
Creative
Moral
Cultural

31. Placing a Value on the Environment
Utilitarian- the environment has value because it benefits individuals economically or is necessary for human survival.
Ecological- ecosystem is necessary for survival of some species of interest or that the system itself provides benefit.

32. Placing a Value on the Environment
Aesthetic- has to do with our appreciation of the beauty of nature.
Recreational- viewing organisms in a natural setting.
Inspirational- to benefit the inner self
Creative- aid to human creativity

33. Placing a Value on the Environment
Moral- the belief that various aspects of the environment have the right to exist and it is our obligation to allow them to continue.