EcologyEcology

E 2.2 Cycles in NatureE 2.2 Cycles in Nature

Cycles in NatureCycles in Nature

The amount of water, carbon, The amount of water, carbon, nitrogen, oxygen and other materials nitrogen, oxygen and other materials for life are fixed within the Earth’s for life are fixed within the Earth’s biosphere.biosphere.

Evaporation – liquid water changes Evaporation – liquid water changes into water vaporinto water vapor

This occurs from lakes, rivers, plants, This occurs from lakes, rivers, plants, exhaling, and animal wastes.exhaling, and animal wastes.

Cycles in NatureCycles in Nature

Condensation – water vapor forms Condensation – water vapor forms tiny dropletstiny droplets

Water Cycle – model that shows the Water Cycle – model that shows the movement of water from the surface movement of water from the surface to the atmosphere and backto the atmosphere and back

Cycles in NatureCycles in Nature

Nitrogen Cycle – transfer of the nitrogen Nitrogen Cycle – transfer of the nitrogen from the atmosphere, to the soil, to living from the atmosphere, to the soil, to living organisms, an back to the atmosphereorganisms, an back to the atmosphere

Nitrogen Fixation – bacteria in the soil Nitrogen Fixation – bacteria in the soil forms nitrogen compounds that plants needforms nitrogen compounds that plants need

Most fertilizers contain nitrogen Most fertilizers contain nitrogen compounds.compounds.

Cycles in NatureCycles in Nature

Carbon Cycle – model that shows the Carbon Cycle – model that shows the movement of carbonmovement of carbon

Carbon dioxide is released into the Carbon dioxide is released into the atmosphere.atmosphere.

Carbon dioxide is taken into plants and Carbon dioxide is taken into plants and supplies the carbon that it needs.supplies the carbon that it needs.

Photosynthesis uses carbon to make Photosynthesis uses carbon to make sugar and respiration uses sugar to make sugar and respiration uses sugar to make carbon dioxide.carbon dioxide.

Cycles in NatureCycles in Nature

Water cycleWater cycle EvaporationEvaporation CondensationCondensation Nitrogen cycleNitrogen cycle Nitrogen fixationNitrogen fixation Carbon cycleCarbon cycle