2. Chapter 1 Fundamental issues in Environmental Science

3. What is Environmental Science? A group of sciences that attempt to explain how life is sustained, what leads to problems and how they can be solved. Earth is a system with a set of parts that function together as a whole.

5. Environmental science: how the natural world works Its goal: developing solutions to environmental problems An interdisciplinary field –Natural sciences: information about the natural world –Social sciences: study human interactions and behavior

6. Environment: the total of our surroundings All the things around us with which we interact: Living things Animals, plants, forests, fungi, etc. Non-living things Continents, oceans, clouds, soil, rocks Our built environment Buildings, human-created living centers Social relationships and institutions

7. Fundamental Issues Earth is isolated in the universe and has limited resources Limited resources can only support a limited population

8. Natural resources: vital to human survival Perpetually available: sunlight, wind, wave energy Renewable over short periods of time: timber, water, soil, wildlife? These can be destroyed Non-renewable resources: Oil, coal, minerals These can be depleted substances and energy sources needed for survival

9. Sustainability Overall general idea is to use it but not to use it up. Sustainable society- A way to live our lives and use earths resources in a way that will be able to support future generations Carrying capacity – maximum number of individuals of a species that can be sustained by the environment without lessening the environments ability to sustain that same number of individual in the future.

10. Global Perspective Future generations deal with these issues The actions of many different groups affects everyone else Non-human life affects the planet as well Gaia Hypothesis – life has profoundly changed the planet and that these changes improve the chances that life on Earth will continue. Example – Algae – influences CO 2 and rainfall thus influencing climate

11. Ecological footprint This is the total area each person requires based on the resources we use and the waste we produce

12. The “ecological footprint” The environmental impact of a person or population –Amount of biologically productive land + water –For resources and to dispose/recycle waste Overshoot: humans have surpassed the Earth’s capacity to support us We are using 30% more of the planet’s resources than is available on a sustainable basis!

13. Ecological footprints are not all equal

14. Environmental science Can help us avoid mistakes made by past civilizations –Human survival depends on how we interact with our environment. –Our impacts are now global. –Many great civilizations have fallen after depleting their resources. The lesson of Easter Island: people annihilated their culture by destroying their environment. Can we act more wisely to conserve our resources?

15. What do we know about Earths Past??????

16. Cities Affect the Environment In developed countries =75% of pop. Is urban and 25% is rural In developing countries = 40% of pop. Is urban and 60% is rural Urban centers are commonly locate near rivers

17. People and Nature Principle of environmental unity – the idea that everything affects everything else. Nature provides service functions. Ex. Worms make fertile soil Bees pollinate foods

18. Value on the Environment Utilitarian Justification – valuable because we can use it Ecological Justification – valuable because it is essential to larger life support functions Aesthetic Justification – valuable because its beautiful Moral Justification – value based on ones view of right and wrong

19. Human Population The number of people on this planet has doubled in last 35 years. This is known as a “population bomb” Current estimates put it at 7.2 Billion

20. Exponential growth – increasing by a constant percentage rather a constant amount Doubling time – time it takes pop. to double Exponential growth is incompatible with sustainability

21. Ecosystem This is a community of organisms and that community’s nonliving matter (chemical cycles)in which cycles and energy flow Ex – Rain forest, deep ocean, prairie

22. Balance of Nature These are natural systems that persist in a steady state Humans and natural events disturb this balance

23. Precautionary Principle States that if there is a serious threat we should not wait for scientific proof before acting Ex. Use of chemicals, pesticides, herbicides and drugs Use of fossil fuel Conversion of land Management of wildlife, fisheries and forests

24. The Precautionary Principle is proactive rather that reactive This means that to react when we see trouble coming instead of reacting after the trouble hits.