Chapter 1: Key Themes in Environmental Sciences

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

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

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 • 1992 - 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. The value of the environment based on 8 justifications Utilitarian Ecological Aesthetic Recreational Inspirational Creative Moral Cultural Placing a Value on the Environment

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.