1. Science and the Environment
Chapter 1
Science and the Environment

2. Understanding Our Environment
Environment: a complex web of relationships that connects us with the world we live in
Environmental Science: the study of how humans interact with the environment

3. Goals of Environmental Science
To understand and solve environmental problems
We must be able to identify causes and describe solutions

4. Human Impact
Humans live within the world’s ecosystems and therefore change them as a result of population growth, technology, and consumption
Problems: habitat destruction, pollution, atmospheric changes, over fishing the oceans, poaching, etc.

5. Consequences
If environmental problems are not addressed, ecosystems will be irreversibly damaged
Human populations NEED natural resources in order to maintain and improve their existence

6. Misconception
News stories often focus on efforts to save threatened or endangered species
There can also be problems with overpopulation of species within an ecosystem
Ex: zebra mussels, house sparrows, European starlings, fire ants, kudzu vine

7. Many Fields of Study
Environmental science is an interdisciplinary science (involves many fields of study)
ECOLOGY: the study of how living things interact with each other and with the nonliving environment

8. Major Fields of Study Biology: study of living organisms
Earth Science: study of the Earth’s nonliving systems and the planet as a whole
Physics: study of matter and energy
Chemistry: study of chemicals and their interaction
Social Science: study of human populations

9. Scientists as Citizens
Studying our environment is vital to maintaining a healthy and productive society
Observations by nonscientists are often the first step of addressing a problem

10. Our Environment Through Time
Humans have always altered the environment to suit their needs, often without a regard for its long-term impacts
Early humans were hunter-gatherers (H-G)
(they obtained food by collecting plants and by hunting animals or scavenging their remains)

11. Hunter-Gatherers (H-G)
Early H-G groups were small and migrated from place to place depending on food abundance
Some H-G societies today include aborigines and tribes in New Guinea

12. Extinction
Rapid climate change and over-hunting of some species led to their extinction
Examples: mastodons and mammoths

13. Conservation
Some H-G groups were very aware of the need for conservation
Native Americans did not kill what they could not use
Although they hunted buffalo, it was the American settlers who slaughtered them nearly to the point of extinction

14. Agricultural Revolution
H-G began collecting seeds to plant and domesticating animals to raise food
Agriculture began more than 10,000 years ago

15. Agricultural Revolution
Through agriculture, an area of land was able to support 500X as many people
As populations grew, they began to concentrate in smaller areas which placed pressure on surrounding environments

16. Slash-and-Burn Agriculture
Causes many areas to become unusable after a few years
Common in rainforest areas

17. Industrial Revolution
Mid 1700’s: shift from energy sources such as animal muscle and running water to fossil fuels (coal, oil, natural gas)
Caused major changes in society
Increased the efficiency of agriculture, transportation, and industry

18. Industrial Revolution (I-R)
Large-scale production of goods became common
Farm machinery decreased the amount of human workers needed
Cotton picked by slaves vs. cotton gin

19. Environmental Consequences
Transportation rapidly developed allowing products to be distributed over greater distances
As people experienced a new standard of living, the environment suffered at our expense

20. Salt and Pepper Moth (Biston betularia)
H.G. Kettlewell’s study: both white and black moths exist
BEFORE I-R, white moths were more common (camouflaged on white tree bark with lichens)
AFTER I-R, black moths were more common (camouflaged on soot covered tree bark)

21. Improving Quality of Life
I-R introduced many changes that improved human lives such as indoor plumbing, nutrition, and medical care
As human populations grow, environmental problems increase

22. Rachel Carson
By the 1900’s, pesticides were widely used and caused many health problems that were ignored
Rachel Carson wrote Silent Spring (1962) which called attention to the misuse of pesticides and began the environmental movement

23. Spaceship Earth
Earth is compared to a ship traveling through space that cannot dispose of waste or take on new supplies
Closed system: the only thing that enters is solar energy and the only thing that leaves is heat

24. Closed System Resources can be used up!
Wastes are produced faster than we can dispose of them

25. Environmental Problems
Exist on three different scales: local, regional, and global
LOCAL: Columbiana County
REGIONAL: Northeast Ohio
GLOBAL: Affects the world

26. Main Environmental Problems
Resource depletion
Pollution
Extinction

27. Resource Depletion
Natural resources: any natural substance that living things can use
Examples: air, water, sunlight, soil, minerals, plants, animals, forests, and fossil fuels
When a resource is used up faster than it can be replaced, it will become depleted!

28. Renewable Resources Resources that are continually being replaced
Examples: solar energy, water, soil, air, crops, livestock, trees
Can still be depleted if not managed properly

29. Nonrenewable Resources
Resources that cannot be replaced…once depleted, they are gone FOREVER!
Examples: metals such as iron, copper, and aluminum, minerals such as salt, sand, and clay, fossil fuels

30. Pollution
Contamination of our air, water, or soil that affects the health, survival, or activities of humans or other organisms
Human byproducts are the main causes of pollution
Examples: pesticides, radiation, petroleum products, PCB’s, mercury, CO2

31. Biodegradable Pollutants
Pollutants that can be broken down by natural processes
Example: human sewage

32. Nondegradable Pollutants
Pollutants that do not break down easily
Accumulate in the environment at dangerous levels
Examples: pesticides, mercury, lead, PCB’s

33. Loss of Biodiversity
Biodiversity: the number and variety of species that live in an area
Many species become extinct due to habitat destruction or polluted ecosystems

34. Extinction
Every last individual of a species has died and the species is gone forever
Examples: dodo, passenger pigeon, great auk
Animals and plants are natural resources that we depend on to exist

35. Biosphere
All life on Earth AND the physical environment that supports it
Damage to any part of an ecosystem can have a ripple effect that can negatively impact the entire biosphere
What can YOU do to help protect the world?