1. Understanding Our Environment

2. What is Environmental Science?
Environmental Science is the study of the air, water, and land surrounding an organism or a community

3. Goals of Environmental Science
Understand and solve environmental problems
To do this scientist must study
How our actions alter our environment
The use of natural resources

4. Many Fields of Study
Environmental science is an interdisciplinary science, which means it involves many fields of study
Ecology, the study of interactions of living organisms with one another and their environment, is important to the foundation of environmental science

5. Hunter-Gatherers
Humans have changed the environment by hunting, growing food, and settling
Hunter gathers are people that obtain food by collecting plants and hunting wild animals or scavenging the remains.
Hunter gathers have affected their environment by:
Native American tribes hunted bison
Native Americans set fires to burn the prairies and prevent growth of trees

6. Agricultural Revolution
Agriculture is the raising of crops and livestock for food or other products.
Started in many areas over 10,000 years ago
Allowed populations to grow at unprecedented rate
Changed the food we eat
Many habitats were destroyed as grasslands, forest, and wetlands were replaced with farmland
Caused soil loss, floods, and water shortages

7. Industrial Revolution
Involved a shift from energy sources such as animals and running water to fossil fuels such as coal and oil
Increased efficiency of agriculture, industry, and transportation
Quality of life was improved
Increased sanitation, nutrition, and medical care
Introduced new environmental problems
Pollution and habitat loss
1900s, societies began using artificial substances
We now have plastics, artificial pesticides, and fertilizers
Many of these made life easier, but caused environmental problems

8. Population Growth
The industrial revolution, modern medicine, and sanitation all allowed the human population to grow faster than it ever had before
Producing enough food for large populations has environmental consequences
Habitat destruction
Pesticide pollution
Scientist think the population will double in the 21st century

9. What are the Main Environmental Problems?
Resource Depletion
Pollution
Loss of Biodiversity

10. Supply and Demand
The Law of Supply and Demand is a law of economics that states as the demand for a good or service increases, the value of the food or service also increases.

11. Ecological Footprints
Ecological footprints are calculations that show the productive area of Earth needed to support one person in a particular country.
Estimates:
Land used for crops, grazing, forest products, and housing
Ocean area used to harvest seafood
Forest area needed to absorb the air pollution by fossil fuels

12. Ecological Footprint