Core Idea ESS3: Earth and Human Activity- ESS3.A: Natural Resources/Human Footprint

1. Ocean

1.1. The entire body of saltwater that covers about 71% of Earth.

2. We need to focus on the three R's:

2.1. Reduce

2.1.1. Reuse

2.1.1.1. Recycle

3. Changes to land

3.1. Humans sometimes drain wetlands or cut down forests to build houses and other structures. They sometimes turn fields into landfills for trash. These changes may help humans find shelter and get rid of waste, but they can harm other living things in the environment.

4. Changes to air

4.1. Cars, buses, trains, and other types of transportation use fuels that pollute the air. Factories also pollute the air when they burn chemicals and release gases into the air.

5. Agriculture

5.1. The science, art, and business of cultivating soil, producing crops, and raising livestock.

6. Stream

6.1. A small body of freshwater that flows into a river.

7. Changes to water

7.1. Sometimes humans take too much freshwater from their environment. As a result, a river or stream might dry up, which kills the organisms that once lived there as well as those that may have depended on that water downstream. Humans also dump trash and harmful chemicals into freshwater and saltwater environments, often making the environment unfit for organisms to survive.

8. Changes to living things

8.1. Overhunting and overfishing can harm or destroy populations of organisms. On the East Coast, fish called cod used to be very common. Overfishing caused these populations to decline so much that they are now very rare in these areas. The larger predatory fish that depended on these fish had to move or find other sources of food.