1. Cycles in the Environment
Topic #5

2. The Carbon Cycle Every single living organism contains carbon (C)
Plankton are microscopic plants and animals that float in the ocean.
Once they are dead, decomposing plankton are buried and compressed over time and changed into fossil fuels
These fossil fuels will contain the carbon that was present in the original organisms

3. The Carbon Cycle (cont.)
Carbon is necessary for all life to exist
Plants use carbon dioxide from the air in order to make their food
Moose, mice and many other organisms eat the plants and release the carbon dioxide when they exhale
Wolves, foxes and other organisms eat the moose, mice and other organisms and obtain their stored carbon. They also exhale carbon dioxide CO2

4. The Carbon Cycle (cont.)

5. The Carbon Cycle (cont.)
The carbon cycle includes:
photosynthesis – plants creating food
decomposition of living things – death and decay
respiration – breathing
extraction and burning of fossil fuels (coal, gas, etc)
dissolved carbon dioxide in oceans, lakes, rivers
plus all the carbon dioxide in the atmosphere
NO carbon molecule is ever destroyed – just reworked and moved throughout the carbon cycle

6. The Water Cycle Like carbon, all living things require water
An apple is 84% water, a carrot is 88% water, a tomato is 94% water
Human bodies are 60-70% water
Water is used for carrying food to cell’s in an organism’s body and for carrying away waste

7. The Water Cycle (cont.)
The water cycle is the continuous movement of water through an ecosystem

8. The Water Cycle (cont.) The water cycle involves 4 main processes
The first two processes (evaporation and transpiration) move water up from the Earth into the atmosphere
Evaporation is the process in which liquid water changes into water vapour (gas)
Transpiration is the process in which water that is taken through a plant’s roots, evaporates from the leaves, stem and flowers.

9. The Water Cycle (cont.)
The second set of processes (condensation and precipitation) return water to the Earth.
Condensation is the process in which water vapour (gas) changes into a liquid. Warm air cools the vapour. As the air cools, it is able to hold less water and water is released, forming clouds, fog or dew
Precipitation is the process in which liquid water forms from condensation occurring inside clouds and then falls as rain, sleet, snow or hail.

10. The Water Cycle (cont.)
The other components of the water cycle are ground water and run-off
Ground water is the water in the soil and rocks below the surface of the Earth. People reach ground water by digging wells.
Run-off is water that doesn’t soak into the ground. It runs off the ground into lakes, rivers, streams and oceans.