Water, Air, Land ResourcesChapter 4.3

The Water Planet

Water covers over 70% of the Earth’s surface

Fresh water is a daily necessity for humans.

Less than 1% of all water on Earth is usable fresh water.

Pollution is a major threat to freshwater resources on Earth.

Point source pollution: pollution that comes from a known source and specific location.

Nonpoint source pollution: pollution that does not have a specific point of origin.

Runoff: the water that flows over the land rather than seeping into the ground.

http://www.rrwatershed.org/map/

Earth’s Blanket of Air

Earth’s atmosphere is a blanket of nitrogen, oxygen, water vapor, and other gases.

The atmosphere cycles material as well, making nutrients available to living things.

Ozone layer: layer in the stratosphere where ozone (O₃) is concentrated, these gases protect us from harmful UV-B rays, which can cause sunburns and lead to skin cancer.

O₃ was being depleted greatly by ozone-depleting chemicals such aschlorofluorocarbons (CFCs).

Greenhouse gases (GHGs): gases in the atmosphere that trap heat and help maintain warm temperatures on Earth.

Too many of these greenhouse gases has led to increased temperatures and overall global warming.

Air pollution can change the chemical composition of the atmosphere and disrupt its natural cycles.

http://www.sparetheair.org/Air Pollution in China

Land Resources

Earth’s land provides soil and forests, minerals, and energy resources.

Removing and using land resources from Earth’s crust can have a big environmental impact.

Soil degradation: an effect where soil is degraded due to heavy usage and poor management.

Deforestation involves clearing forested land to convert it to farming, ranch, or urban areas. Deforestation