1. Science & The Environment
Section #1:
Understanding Our Environment

2. What exactly does the term ENVIRONMENT mean?
includes everything around you
natural world
things produced by humans
more that just what can be seen by the naked eye
complex web of relationships – everything is connected to everything else

3. Discussion Question:
It is often difficult for people to reach an agreement about environmental issues.
Why?

4. What is Environmental Science?
the study of how humans interact with the environment
major goal = to understand & to solve environmental problems
focus on how we use natural resources & how our actions alter our environment

5. Fields of Study
Biology – living organisms (zoology, botany, microbiology, ecology)
Earth Science – nonliving systems (geology, paleontology, climatology, hydrology)
Physics – matter & energy (engineering)
Chemistry – chemicals & their interactions (biochemistry, geochemistry)
Social Sciences – human populations (geography, anthropology, sociology)

6. An Interdisciplinary Science
One field plays a key role . . .
Ecology – the study of how living things interact with each other and with their nonliving environment

7. How Have We Changed Our Environment Over Time?

8. How Have We Changed Our Environment Over Time?
Hunter-Gatherers
small groups that migrated to find food
burned prairies to maintain open grasslands for some species
spread plants to other areas
over-hunting lead to disappearance of some species (mass graves)

9. How Have We Changed Our Environment Over Time?

10. How Have We Changed Our Environment Over Time?
Agricultural Revolution (10,000 yrs. ago)
stopped migrating, staying in one place
smaller areas could support greater populations leading to rapid population growth
saved seeds of the “good” plants, leading to the domestication of wild plants
slash & burn destroyed habitats, leading to soil loss, flooding, water shortages
over time the fields lost fertility

11. How Have We Changed Our Environment Over Time?

12. How Have We Changed Our Environment Over Time?
Industrial Revolution (mid 1700s)
shift in animal power to fossil fuels
how did this change society?
how did this change the efficiency of
agriculture
industry
transportation

13. Discussion Question:
How have the things that make life easier also lead to more problems?
What are some more recent problems we’re facing as technological advances continue?

14. What is a CLOSED system?
Earth – it cannot get rid of used material nor can it take on new supplies
What problems do you see on a
local scale?
regional scale?
global scale?

15. Compare the differences in population growth in the past 50 years
Compare the differences in population growth in the past 50 years. Why do you think this is happening?

16. Population Growth
being able to produce more food & transport that food to a sprawling nation has spurred a growth in the world’s population
improvements to modern medicine & sanitation have also added in the survival rate

17. Graph – Population Growth

18. What are Our Main Environmental Problems?
Resource Depletion
Pollution
Loss of Biodiversity

19. Resource Depletion Renewable vs. Nonrenewable
Any natural resource, renewable or nonrenewable, can become depleted when a large fraction of the resource has been used up

20. Pollution
An undesired change in air, water, or soil that adversely affects the health, survival, or activities of humans or other organisms
Name some forms of pollution from human activites

21. 2 Types of Pollutants
Biodegradable = can be broken down by natural processes (ex. include human sewage & a stack of newpapers)
Nondegradable = cannot be broken down by natural processes (ex. include mercury, lead, some types of plastic)

22. Loss of Biodiversity
Extinctions, even mass extinctions, are a natural process & have occurred many times in Earth’s history
Some scientists believe the rate of current extinctions is high & this may cause problems for humans down the road