1. Cycling of Matter 4.3 “biogeochemical” cycles 1.WATER 2.CARBON-OXYGEN 3.NITROGEN 4.PHOSPHORUS

2. WATER (H 2 0) CYCLE The continual movement of H 2 0 from the Earth’s surface and oceans to the atmosphere and back to the surface and oceans again. Powered by the sun (solar energy) which causes evaporation & transpiration (water loss from plants). Cells: 70-90% water…Earth: 75% water …water is a KEY factor in terrestrial ecosystems!!

3. DRAW IT!! Poster… BLUE ARROWS precipitation (forms: rain, snow, sleet, hail, fog) transpiration (aka evapotranspiration) evaporation runoff water vapor percolation (water into soil) ground water (water in soil)

4. CARBON (C) CYCLE CO 2 to plants  photosynthesis (requires sunlight and H 2 0 too!)  carbohydrates carbohydrates  consumers (AND PLANTS!)  respiration respiration  back to CO 2 and biomass.

5. PHOTOSYNTHESIS stores solar energy in the form of C-C bonds in organic compounds (glucose!). RESPIRATION releases chemical bond energy and makes it available (“usable”) to cells…cells need energy to grow, develop, reproduce, respond, maintain homeostasis, etc. Sources: all organisms (including decomposers), natural burning, power plant / factory / vehicle emissions.

6. DRAW IT!! FoldNotes… BLACK ARROWS –Photosynthesis –Cellular respiration (CR) –Decomposition (CR): bacteria & fungi in soil –Combustion –Food chain (consumers…part of CR) –CO 2, O 2, H 2 0, Sun

7. NITROGEN (N) CYCLE Air contains ~78% N 2 gas N 2 gas must be converted into other compounds (nitrates) before it can be used by plants called nitrogen fixation (done by bacteria)  then by other living things. Plants use the nitrogen compounds they absorb through their roots (a process called assimilation) to make amino acids, proteins, and other important substances. Animals get the nitrogen they need by consuming plants or organisms that consume plants.

8. Others! Decomposers play an important role by breaking down N-containing animal wastes and the remains of dead organisms  similar process to nitrification. Another type of bacteria converts some of the ammonia and nitrates into free N 2 gas  back into atmosphere…this is called denitrification.

9. DRAW IT!! FoldNotes… GREEN ARROWS Ammonia N 2 (nitrogen gas), H 2 0 Nitrogen fixation Denitrification Nitrogen-fixing bacteria Nitrates Assimilation (occurs through plant roots) Denitrifying bacteria Decomposers Death/waste

10. PHOSPHORUS (P) CYCLE P is a component of ATP (energy storing compound used by cells) and is a component of DNA (genetic code) Found in soil and rock as calcium phosphate which dissolves in H 2 0 to form phosphate  plants absorb through their roots  animals eat plants (P is transferred)  animals and plants die  phosphorus is returned to soil.

11. http://www.marietta.edu/~biol/102/ecosystem.html#top

12. DRAW IT!! FoldNotes…RED ARROWS Key words on previous slide.