1. Ecology E 2.2 Cycles in Nature

2. Cycles in Nature  The amount of water, carbon, nitrogen, oxygen and other materials for life are fixed within the Earth’s biosphere.  Evaporation – liquid water changes into water vapor  This occurs from lakes, rivers, plants, exhaling, and animal wastes.

4. Cycles in Nature  Condensation – water vapor forms tiny droplets  Water Cycle – model that shows the movement of water from the surface to the atmosphere and back

7. Cycles in Nature  Nitrogen Cycle – transfer of the nitrogen from the atmosphere, to the soil, to living organisms, an back to the atmosphere  Nitrogen Fixation – bacteria in the soil forms nitrogen compounds that plants need  Most fertilizers contain nitrogen compounds.

9. Cycles in Nature  Carbon Cycle – model that shows the movement of carbon  Carbon dioxide is released into the atmosphere.  Carbon dioxide is taken into plants and supplies the carbon that it needs.  Photosynthesis uses carbon to make sugar and respiration uses sugar to make carbon dioxide.

11. Cycles in Nature  Water cycle  Evaporation  Condensation  Nitrogen cycle  Nitrogen fixation  Carbon cycle