2. Cycles of Matter

3. All matter cycles...it is neither created nor destroyed... The Earth is essentially a closed system with respect to matter, we can say that all matter on Earth cycles.

4. Biogeochemical cycles: the movement (or cycling) of matter through a system. We will look at 4 cycles.

5. Hydrological or Water Cycle

6. Many processes work together to keep Earth's water moving in a cycle. There are six processes:

7. Condensation Precipitation Runoff Infiltration (seepage) Evaporation Transpiration

8. Condensation: process of water changing from a vapor to a liquid

9. Precipitation is water being released from clouds as rain, sleet, snow, or hail.

10. Infiltration (seepage): water that seeps into the ground. Precipitation that reaches the surface of the Earth but does not infiltrate the soil is called runoff.

11. Evaporation: water changing from a liquid to a gaseous form. Transpiration: H 2 0 evaporating from plant leaves.

12. Water cycle

13. Carbon Cycle 4 different processes involved in the Carbon Cycle: 1) Biological photosynthesis, respiration & decaying of plants and animals.

14. 2) Geochemical release of carbon dioxide gas (CO 2 ) by volcanoes.

15. 3) Mixed biogeochemical fossil fuels

16. 4) Human activity burning fossils fuels, burning and cutting forests

17. Nitrogen Cycle All organisms need nitrogen to build amino acids. Nitrogen gas (N 2 ) is the most abundant form of nitrogen 78% of Earth’s atmosphere

18. However only certain bacteria can use N 2 so they convert nitrogen gas into ammonia (nitrogen fixation) which then other bacteria make nitrates and nitrites which can be used to make proteins

19. Decomposers: Return nitrogen to the soil in the form of ammonia…it can be taken up again or…

20. Go through a process called denitrification. Bacteria in the soil convert nitrates (NO 3 - ) and (NO 2 - ) into nitrogen gas (N 2 ).

21. Phosphorus Cycle

22. The largest reservoir of phosphorus is in sedimentary rock.

23. The cycle starts with the introduction of phosphate (PO 4 ) into soils from the weathering of rocks which then enter the ecosystem through plants.

24. Plants Animals Herbivores Carnivores Phosphate (PO 4 ) Movement of Phosphorus PO 4

25. Carnivores Soil Movement of Phosphorus PO 4 Urine & Feces Decomposition of dead animals Dead plants PO 4

26. Primary Productivity: rate of organic matter that is created by producers What limits production? Availability of nutrients

27. Limiting nutrient: when growth is limited by a single nutrient that is scarce. Examples?

28. Algal bloom: Lots of nutrients = Lots of algae grow = Lots of food, but what if there are not enough consumers? Look at pg. 494/ 16.3 What is it called when lakes & ponds slowly begin to fill?