1. Cycling of Matter 13.5

2. Hydrologic Cycle
Hydrologic cycle: circular pathway of water on Earth from the atmosphere to the surface, below ground, and back
4 pathways

3. 4 Pathways
1.) Precipitation: rain or snow falls to ground from the atmosphere
2.) Evaporation: water reenters the atmosphere
3.) Transpiration: evaporation that occurs between plant leaves and the atmosphere
4.) Condensation: water vapor condenses and forms clouds which return water back to the surface

4. Hydrologic Cycle precipitation condensation transpiration evaporation
Surface
runoff
seepage
groundwater

5. Biogeochemical Cycles
Movement of a particular chemical through the biological (living) and geological (nonliving) parts of an ecosystem
- Oxygen cycle
- Carbon cycle
- Nitrogen cycle
- Phosphorus cycle

6. Oxygen Cycle
Oxygen cycles indirectly through an ecosystem by the cycling of other nutrients
The main processes involved in the oxygen cycle are photosynthesis and respiration

7. Plants release oxygen as a waste product during photosynthesis
Humans & other organisms take oxygen in and release it as CO2 through respiration

8. Oxygen Cycle
oxygen
photosynthesis
respiration
Carbon
dioxide

9. Carbon Cycle
Carbon is the building block of life—it is an essential component of carbohydrates, proteins, fats, & other organic molecules in our bodies
Carbon moves from the atmosphere through photosynthesis then through the food web

10. Carbon is returned to the atmosphere as CO2 by respiration or the decomposition of dead organisms
The burning of fossil fuels also adds carbon to the atmosphere

11. Carbon Cycle CO2 In air respiration combustion photosynthesis
Decomposition of
organisms
Fossil
fuels

12. Nitrogen Cycle Most of the nitrogen cycle takes place underground
Nitrogen fixation: bacteria convert gaseous nitrogen from the atmosphere into ammonia NH3

13. Some nitrogen fixing bacteria live on the roots of plants while others live in the soil
Denitrifying bacteria release nitrogen gas back into the atmosphere

14. plants Nitrifying bacteria
animals
Nitrogen in atmosphere
plants
Denitrifying
bacteria
Nitrogen-fixing bacteria in roots
nitrates
decomposers
Nitrifying bacteria
Nitrogen-fixing bacteria in soil
nitrites
ammonium

15. Phosphorus Cycle
Takes place at & below ground level—does not include the atmosphere
Phosphate is released by the weathering of rocks
Phosphorous moves through food web and returns to soil during decomposition

16. Phosphorus leaches into groundwater from the soil and is locked in sediments
Weathering of phosphate
In rocks
Plants & animals
Phosphate
In soil
leaching
decomposers
Sedimentation forms
New rocks

17. Cycles of Matter Posters
Create a poster with your group illustrating your assigned cycle. Your poster boards should include:
Elements essential to the cycle
The processes involved in each cycle
The direction of the flow of nutrients
The information is the most important part of your poster. Get it down first, then add pictures. You may draw these or cut them out from magazines