World Geography: Human/Environment Interaction

Human Changes to the Environment

Humans can positively and negatively affect the environment. When you have an effect, or leave your mark, on the environment, you are said to leave your “footprint.”

Negative changes affecting the environment include the following:

• Overpopulation
• Polluted air and water
• Deforestation
• Depleting the atmosphere’s ozone level

Results of negative changes are given in this table.

Overpopulation	Using too many natural resources, making more living space while reducing greenspaces, damaging ecosystems, depleting forests, using too many fossil fuels, increasing levels of gases in the air to cause global warming and climate change
Polluted air and water	Smog, coral reefs die, garbage in waters causes impure waters, marine life starves and dies from plastics in waters, acid rain due to too much carbon dioxide in air
Deforestation	More greenhouse gases, removal of animals’ habitats, depleted soil, loss of building materials
Ozone depletion	Atmosphere unable to absorb ultraviolet light, more gases in atmosphere, eye damage, skin cancers

Humans also affect the environment in positive ways, such as the following:

• Protecting endangered species
• Recycling
• Establishing parks and wildlife preserves
• Developing greenspaces
• Establishing government agencies such as the Environmental Protection Agency
• Avoiding littering
• Reforesting

BE CAREFUL!
The footprint you leave on Earth depends on the way you interact with the environment. It may be positive or negative!

Example

When Earth’s ozone level in the atmosphere is decreased, _______________.

A. acid rain occurs
B. soils become more acidic

C. greenspaces are difficult to establish
D. people may be at higher risk of skin cancer

The correct answer is D. Ultraviolet rays cannot be properly absorbed when the ozone layer is depleted. Ultraviolet rays can cause skin cancer.