1. Environmental Science
Understanding and solving environmental problems

2. Humans through history
Hunter-gathers- caused some animals to become extinct
Agricultural revolution-caused human population to grow and destroyed land.
Industrial revolution- shift to fossil fuels. Improved quality of life for people but allowed for urban areas to flourish.

3. The Earth is a closed system
Limited resources
Population increase causes a strain on resources
We produce wastes (pollution) that we can not get rid of.
We have local and global environmental issues.

5. What are our main Environmental Problems?
Resource depletion- Using our resources up faster that they can be replaced.
Natural resource- any natural resource that is used by humans
a. renewable resource- resources that can be replaced relatively quickly
ex. Trees, water, soil, air and crops
b. Nonrenewable resource- can not be replaced quickly
Ex. Fossil fuels, minerals, and metals

6. What are our main Environmental Problems?
2. Pollution- undesired change in air, water or soil that has adverse affects.
a. biodegradable pollutants- can be broken down by natural processes.
ex. Human sewage and paper
b. nonbiodegradable pollutants- can not be broken down by nature.
ex. Mercury, lead, and some types of plastic

7. What are our main Environmental Problems?
3. Loss of biodiversity- refers to the number and variety of species that live in an area.
Endangered species-A species that is in danger of becoming extinct
Threatened species-a species that numbers are falling rapidly

8. Endangered species

9. Tasmanian
tiger
Declared
Extinct
In 1986

10. Threatened species