1. Science and the Environment
Understanding Our Environment

2. Section Objectives
List the five major fields of study associated with Environmental Science
Describe the major effects of hunter-gatherers, the Agricultural Revolution, and the Industrial Revolution.
Distinguish between renewable and nonrenewable resources
Classify environmental problems into three major categories

3. Environmental Science
The study of air, water, and land surrounding an organism or a community
Included:
Impact of humans
Small areas
Earth’s biosphere

4. Interdisciplinary Science

5. Environmental Science
To understand and solve environmental problems
Studies human use of resources
Studies impact of human use

6. Environment Through Time
Hunter-gatherers- Obtained food by collecting plants, hunting and/or scavenging animals
Burned grasslands
Killed buffalo in large numbers
Over hunting caused extinctions of:
Giant sloth
Giant bison
Mastadons
Cave bears
Saber-toothed cats

7. Hunted to Extinction

8. Hunter-Gatherers

9. Environment Through Time
The Agricultural Revolution- Growing and raising food for human consumption
Started over 10,000 years ago
Human populations increased dramatically
Concentrations of people affected environment
Domesticated plants from wild plants
Slash and burn
Causes soil loss, floods, and water shortage
Poor farming practice rendered = useless land

10. The Agricultural Revolution

11. Environment Through Time
Industrial Revolution- Shift to using fossil fuels
Efficiency of agriculture, industry, and transportation
Mass production = lower cost
Machinery reduced land and human labor needed
Human populations grew at an extraordinary rate
Urban areas grew = more pollution and habitat loss
Improvements:
Inventions- Light bulb, plastics, pesticides, fertilizers
Sanitation
Nutrition
Medical care

12. The Industrial Revolution

13. Local

14. Spaceship Earth Earth is a closed system
Nothing enters but energy from sun
Nothing leaves except for heat
Some resources are limited
Waste produced faster than disposal

15. Today’s Problems Local problems- Landfills
Regional problems- River water shortage
Global problems- Ozone depletion & global warming

16. Resource Depletion Resource depletion- Large fractions used up
Natural resources-
Renewable- Can be replaced within a human lifetime
Nonrenewable- Can’t be replaced within a human lifetime

17. Pollution
Undesirable change in environment caused by introducing harmful substances, excessive waste, heat, noise or radiation
Biodegradable-Can be broken down by natural processes
Build up faster than broken down
Nondegradable-Can’t be broken down by natural processes
Build up at dangerous levels

18. Pollution

19. Loss of Biodiversity
Biodiversity- Variety of organisms in a given area
Genetic variety in a population
Variety of species in community
Variety of communities in ecosystem
Extinction- none left
Preservation important