Environment

1. Pollution

1.1. Plastics

1.1.1. Monomer and polymer

1.1.2. Hottest temperature

1.1.3. Pressure

2. Nature

2.1. Water

2.1.1. Rivers

2.1.2. Oceans

2.1.3. Rain

2.2. Dirt

2.2.1. Vegetation

2.2.2. Plants

2.2.3. Forest

2.2.3.1. Trees

2.3. Ecosystems

2.3.1. Animals

2.3.2. Gaps

2.3.3. Sun

2.3.4. Fruits

2.3.4.1. Vegetables

3. Natural resources

3.1. Fossil Fuels

3.1.1. Oil

3.1.2. Gasoline

3.1.3. Gas

3.2. Ozone layer

3.2.1. Greenhouse Effect

4. Extinction

4.1. Contamination

4.2. Deforestation

4.3. Overpopulation

4.4. Wildfires

4.5. Droughts

4.6. Global warming

5. Natural phenomena

5.1. Earthquake

5.1.1. Tsunami

5.1.1.1. Floods

5.2. Landslide

5.3. Volcanic eruption

5.4. Sky

5.4.1. Clouds

5.4.2. Rainbow

5.5. Weather

5.5.1. Hot

5.5.2. Could

5.6. Seasons

5.6.1. Spring

5.6.2. Summer

5.6.3. Fall

5.6.4. Winter

6. Environmentalism

6.1. Recycle

6.2. Care for the natural resources

6.3. Use the bike

7. Destruction of the environment

7.1. Construction

7.2. Nuclear disasters

7.3. Extraction of fossil fuels