1. THE CARBON CYCLE

2. CARBON Carbon is the key element for living things. It can be found in almost any part of nature, from plants to animals, and from the ground to the atmosphere.

3. THE CARBON CYCLE The movement of carbon on Earth creates a cyclical pattern as it transmits through different forms between the biosphere, atmosphere, geosphere and hydrosphere.

4. THE CARBON CYCLE

5. There are 5 main factors that contribute to the carbon cycle:

6. 1. PHOTOSYNTHESIS Plants “capture” carbon from the atmosphere in the form of CO 2 to make carbohydrates. Some of these sugars are converted into fats or protein.

7. 2. RESPIRATION Animals AND plants (in the absence of light) use carbohydrates as energy and produce CO 2 through cellular respiration. This is a very detailed and complex process.

8. 3. DECOMPOSITION Decomposers break down plant and animal materials. During this process, CO 2 is released into the atmosphere.

9. 4. FOOD CHAINS Carbon is passed through trophic levels as organisms feed on each other. Carbon moves up the food chain quite easily.

10. 5. COMBUSTION Over time, detritus settles into the ground much like sediments on the bottom of oceans and lakes. Carbon compacts over geologic time (eons of years). This process creates fossil fuels which are burned for energy.

11. 5. COMBUSTION Along with deforestation and volcanic action, combustion of fossil fuels releases CO 2 back into the atmosphere.

12. CARBON RESERVOIRS Carbon is stored in various forms on Earth in reservoirs. Most of Earths CO 2 is stored in oceans and lakes. Plants and algae use it for photosynthesis.

13. CARBON RESERVOIRS Most of it ends up as sediment, which eventually becomes rock. Limestone traps carbon until volcanic actions release CO 2, as they can break down sedimentary rock. Acid rain also causes the release of CO 2.

14. CARBON RESERVOIRS Living organisms also store carbon. Fortunately (or unfortunately), all living things die, and decomposition eventually returns carbon back to the atmosphere.

15. THE CARBON CYCLE