1. Chapter 3
Ecosystem Management

2. Humans and Their Environment
People have always lived in an environment
In the past, our impact was smaller
hand tools, smaller populations, etc.
With technology, our impact has increased

3. Managing Natural Resources
Active role in caring for environment
Need to understand how environment works
Must gather information about environment health

4. Managing Natural Resources
Environmental issues require their own solutions
Each issue is different
Each issue should be considered separately

5. Natural Resources Everything in environment is natural resource
Any object used to perform work
Any object with potential to perform work

6. Natural Resources Nonexhaustible resources Examples could last forever
continuously renewed
does not mean they are not limited
Human misuse can still damage resource
Examples
water and air

7. Natural Resources Renewable resources
Resource can be replaced by human efforts
Use should be restricted
used no faster than can be regenerated
Does not mean it will never be used up
Examples
forests, fish populations, wildlife populations

8. Natural Resources Nonrenewable or exhaustible resources
resources that cannot be replaced or reproduced
exist in finite amounts
do not renew themselves
We can learn to
conserve, use less, and recycle

9. Natural Resources
Although a natural resource may be finite, it is not necessarily limited

10. Nonrenewable and Exhaustible Resources
Examples
oil, lead, cobalt, zinc
even soil
constantly being formed
Why not a nonexhaustible resource?
Nature makes soil too slowly

11. Nonrenewable and Exhaustible Resources
Nonrenewable also means renewed too slowly

12. Balance of Nature No such thing as balance of nature
Forces of nature constantly produce change: continuous and natural
It is essential that change be gradual
Managing resources wisely requires careful use
using resources slowly and gradually

13. Carrying Capacity Population Carrying capacity
number of individuals in given area
Carrying capacity
population level an ecosystem can support
number of individuals that can get resources
Populations that exceed carrying capacity
experience disease, predation, starvation

14. Human Population Human population through the years
6000 B.C. = approximately 10 million people
Birth of Christ = approximately 300 million
A.D = almost 1 billion people
1900 = 1.6 billion
1979 = 4.3 billion
1999 = 6 billion

15. Human Population
What is the Earth’s carrying capacity?

16. Conservation Protecting natural resources against harm and waste
Involves
using less so resource available in future
not using resources wastefully or carelessly

17. Conservation Resources are not to be set aside should be used
should be managed for future use, too

18. Conservation Soil necessary for farms, human use
maintaining wildlife habitats
Soil erosion greatest source of water pollution

19. Conservation Soil conservation protecting soil from wind and water
minimizing erosion
keeping soils fertile and productive

20. Preservation Maintaining resource in natural state
simply because we value it
We must balance our desires
for preservation with needs as a people

21. Questions for this generation:
Preservation
Questions for this generation:
Can we set aside certain resources?
Which is more important:
economic growth or preservation?

22. Protecting Resources Pollution must find origin and reduce release
may even involve cleanup

23. Protecting Resources Water Pollution
mostly from untreated sewage and industrial waste
Clean Water Act of 1972
did much to reduce water pollution

24. Protecting Resources Air pollution acid rain smog
caused by weak acids forming in rain
smog
pollution reacts with UV radiation
forms cloud of polluted air

25. Protecting Resources Main sources of air pollution
exhaust
coal and petroleum combustion
Must reduce amount of exhaust and combustion products