BIOGEOCHEMICAL CYCLES

Biogeochemical

Big word; simple idea Bio = life Geo = earth Chemical = substanceSo biogeochemical = substances involved with life on earth.

Water Cycle

Water Is Everywhere

75% of the earth’s surface is covered with water.

All living things contain water.

There is water in the atmosphere.

Water on the Move

Water continually cycles from the earth to the atmosphere and back again.

Evaporation

Water evaporates (changes from a liquid to a gas).

Condensation

Water condenses (changes from a gas to a liquid).

Precipitation

Water returns to earth’s surface in the form of rain, sleet, snow or hail.

The Very Simple Version

Evaporation

Condensation

Precipitation

It’s more complicated than that.

Transpiration

Plants return water to the atmosphere.

Plant sucks in water through roots

Plant loses water through leaves

Perspiration

Animals return water to the atmosphere when they sweat, pant, breathe, etc.

Infiltration

Water goes into the ground. It filters through soil, rocks, etc.

Diagram courtesy of the U.S. Geological Survey

Runoff Some water moves along the surface of the ground collecting in low areas.

Diagram courtesy of the U.S. Geological Survey

Ground Water

Water filters into soil and rock until it comes to rocks it cannot pass through.

Water may fill spaces in rocks and soil.

An aquifer is a pool of underground water.