1. Key Themes in Environmental Sciences
Chapter 1
Key Themes in Environmental Sciences

2. Major Themes of Environmental Science
Human population growth
An urbanizing world
Sustainability of our population and all of nature
People and nature
A global perspective
Science and values

3. Human Population Growth
The human population grew at a rate unprecedented in history in the twentieth century.
Population growth is the underlying environmental problem.
Famine is one of the things that happen when a human population exceeds its environmental resources. An example is African Famine.

4. Population change since 1950 projected to the year 2150 for major areas of the world, medium fertility scenario. The population of Africa will nearly quadruple. The only major area whose population is projected to drop over time is Europe – from 728 million to 595 million, a decline of 18% over 155 years.
© 2008 John Wiley and Sons Publishers

5. Sustainability and Carrying Capacity
What is the maximum number of people the Earth can sustain? (What is the sustainable human carrying capacity of the Earth?)
We are using our renewable environmental resources faster than they can be replenished.

6. Sustainability Sustainable resource harvest Sustainable ecosystem
An amount of a resource that can be harvested at regular intervals indefinitely
Sustainable ecosystem
An ecosystem that is subject to some human use, but at a level that leads to no loss of species or of necessary ecosystem functions

7. Understanding Sustainability
Sustainability means for an unspecified long period of time.
Sustainable growth is an oxymoron as any steady growth (fixed percentage growth per year) produces large numbers in modest periods of time.
Botkin & Keller
Environmental Science 5e

8. A Sustainable Global Economy must include:
Populations (humans and other organisms) living in harmony
An energy policy that doesn’t pollute, cause climate change or present unacceptable risk
A plan for renewable and nonrenewable resources that doesn’t deplete or damage resources
A social, legal, and political system that is dedicated to sustainability
Botkin & Keller
Environmental Science 5e

9. A Sustainable Global Economy is achieved by:
Developing an effective population-control strategy.
Completely restructuring our energy programs.
Instituting an economic plan, which includes a tax structure that encourages population control and wise use of resources.
Implement social, legal, political and educational changes that maintain a quality local, regional, and global environment.
Botkin & Keller
Environmental Science 5e

10. Moving toward Sustainability
A sustainable future requires an evolution in our values that involves our lifestyles as well as social, economic, and environmental justice.
Sustainability must include all people of Earth.
Sustainability involves planning for change (population problems, resource shortages).
People must be attracted to sustainability because it is right and just (sound scientific argument and appropriate values).
Botkin & Keller
Environmental Science 5e

11. Environmental Science 5e
Carrying Capacity
The maximum number of individuals of a species that can be sustained by an environment without decreasing the capacity of the environment to sustain that same amount in the future.
Depends in part on our values.
Botkin & Keller
Environmental Science 5e

12. Environmental Science 5e
A Global Perspective
Global versus local food production
Transportation of food
Nonhuman life affects the environment of our whole planet
Civilization can change the environment at global levels
Emissions
Fossil fuel consumption
Gaia hypothesis
Botkin & Keller
Environmental Science 5e

13. An Urban World
When the impact of technology is combined with the impact of population, the impact on the environment is multiplied.
In an increasingly urban world, we must focus much of our attention on the environments of cities and on the effects of cities on the rest of the environment.

14. Environmental Science 5e
People and Nature
Path One: assume environmental problems are the result of human actions and that the solution is simply to stop these actions
People separate from nature
Confrontation and emotionalism
Path Two: begin with a scientific analysis of an environmental controversy
Cooperative problem solving
Connection between people and nature
Botkin & Keller
Environmental Science 5e

15. Science and Values
To make decisions about an environmental problem we must:
Know what is possible based on science
Choose the best option based on our values
Find a way to attain that goal

16. Precautionary Principle
Precautionary Principle states that we should not wait for scientific proof before taking action to prevent environmental damage.
Ex. San Francisco

17. Value and the Environment: Justifications
Utilitarian: benefits individuals economically (materialistic)
Ecological: ecosystem is necessary for the survival of some species of interest to us (mangroves)
Botkin & Keller
Environmental Science 5e

18. Environmental Science 5e
Justifications
Aesthetic: appreciation of the beauty of nature
Recreational: hiking, camping, photography
Inspirational: to benefit our “inner selves”
Botkin & Keller
Environmental Science 5e

19. Environmental Science 5e
Justifications
Moral: various aspects of the environment have a right to exist and it is our moral obligation to allow them to continue and persist
Cultural: religious beliefs and practices (diet, number of children) can influence how many value their environment
Botkin & Keller
Environmental Science 5e