2. Flow of Matter (2.3)
State Standard
SB4B. Explain the flow of matter and energy through ecosystems by
Explaining the need for cycling of major nutrients (C, O, H, N, P).

3. CYCLES IN THE BIOSHPHERE
Chapter 2
Principles of Ecology
2.3 Cycling of Matter
CYCLES IN THE BIOSHPHERE
Energy is transformed into usable forms to support the functions of an ecosystem. There must be a constant supply.
Unlike energy, matter is constantly being recycled & reused.
The cycling of nutrients in the biosphere involves both matter in living organisms and physical processes found in the environment such as weathering.

4. Chapter 2
Principles of Ecology
2.3 Cycling of Matter
THE WATER CYCLE

5. Chapter 2
Principles of Ecology

6. Freshwater constitutes only about 3 percent of all water on Earth.
Chapter 2
Principles of Ecology
2.3 Cycling of Matter
THE WATER CYCLE CONT’D
Approximately 90 percent of water vapor evaporates from oceans, lakes, and rivers; 10 percent evaporates from the surface of plants through a process called transpiration.
Freshwater constitutes only about 3 percent of all water on Earth.
About 69 percent of all freshwater is found in ice caps and glaciers.

7. THE CARBON & OXYGEN CYCLES
Chapter 2
Principles of Ecology
2.3 Cycling of Matter
THE CARBON & OXYGEN CYCLES

8. Chapter 2
Principles of Ecology

9. Carbon and oxygen often make up molecules essential for life.
Chapter 2
Principles of Ecology
2.3 Cycling of Matter
THE CARBON & OXYGEN CYCLES CONT’D
Carbon and oxygen often make up molecules essential for life.
Carbon and oxygen recycle relatively quickly through living organisms.
The carbon & oxygen cycles are closely connected.

10. Carbon has both long & short-term cycles. Long-term Cycle
Chapter 2
Principles of Ecology
2.3 Cycling of Matter
THE CARBON & OXYGEN CYCLES CONT’D
Carbon has both long & short-term cycles.
Long-term Cycle
Organic matter converted to peat, coal, oil, or gas deposits (fossil fuels) – involves C only
Calcium carbonate (limestone) – involves C&O
Short-term Cycle
Photsynthesis/Cellular Respiration (C&O)
Burning fossil fuels - involves C only

11. Chapter 2
Principles of Ecology

12. Nitrogen does not have a long-term cycle!
Chapter 2
Principles of Ecology
2.3 Cycling of Matter
THE NITROGEN CYCLE
Nitrogen does not have a long-term cycle!
The capture and conversion of nitrogen into a form that is usable by plants is called nitrogen fixation.

13. Chapter 2
Principles of Ecology
2.3 Cycling of Matter
THE NITROGEN CYCLE CONT’D
Nitrogen enters the food web when plants absorb nitrogen compounds from soil.
Consumers get nitrogen by eating plants or animals that contain nitrogen.

14. Nitrogen is returned to the soil in several ways:
Chapter 2
Principles of Ecology
2.3 Cycling of Matter
THE NITROGEN CYCLE CONT’D
Nitrogen is returned to the soil in several ways:
Animals urinate.
Organisms die.
Organisms convert ammonia into nitrogen compounds.
Denitrification
process by which fixed nitrogen compounds are converted back
Into nitrogen gas & released

15. THE PHOSPHOROUS CYCLE Chapter 2 Principles of Ecology
2.3 Cycling of Matter
THE PHOSPHOROUS CYCLE

16. Chapter 2
Principles of Ecology

17. Chapter 2
Principles of Ecology
2.3 Cycling of Matter
THE PHOSPHOROUS CYCLE CONT’D
Phosporous has both long & short-term cycles.
Short-term Cycle
Phosphorus is cycled from the soil to producers and then from the producers to consumers.
Long-term Cycle
Weathering or erosion of rocks that contain phosphorus slowly adds phosphorus to the cycle.

18. SUMMARY 1
Biogeochemical cycles include the exchange of important elements between the abiotic & biotic parts of an ecosystem.
The carbon & oxygen cycles are closely intertwined.

19. SUMMARY 2
Nitrogen gas is limited in its ability to enter biotic portions of the environment.
Nitrogen is the only 1 that does not have a long-term cycle.

22. Chapter 2
Principles of Ecology
Chapter Diagnostic Questions
What is a chemical substance that an organism must obtain from its environment to survive?
biomass
energy
matter
nutrient D C B A
CDQ 3

23. What type of organism returns nutrients to an ecosystem?
Chapter 2
Principles of Ecology
2.3 Formative Questions
What type of organism returns nutrients to an ecosystem?
decomposer
primary producer
secondary producer
top level consumer D C B A
FQ 7

24. Chapter 2
Principles of Ecology
2.3 Formative Questions
What type of scientist studies water found underground, in the atmosphere, and on the surface of the earth?
biochemist
ecologist
geologist
hydrologist D C B A
FQ 8

25. Chapter 2
Principles of Ecology
2.3 Formative Questions
Which biogeochemical cycle involves evaporation, transpiration, precipitation and runoff?
carbon cycle
nitrogen cycle
phosphorus cycle
water cycle D C B A
FQ 9

26. combustion of fossil fuels deposition of dead material
Chapter 2
Principles of Ecology
2.3 Formative Questions
Which process in this cycle converts carbon dioxide and water into carbohydrates?
photosynthesis
respiration
combustion of fossil fuels
deposition of dead material D C B A
FQ 10

27. Use the image below to explain how decomposers
Chapter 2
Principles of Ecology
Chapter Assessment Questions
Use the image below to explain how decomposers
supply phosphorus to soil, groundwater, oceans,
lakes, ponds, and rivers.
CAQ 3

28. Answer: All organisms contain phosphorus.
Chapter 2
Principles of Ecology
Chapter Assessment Questions
Answer: All organisms contain phosphorus.
When organisms die or produce
waste products, decomposers
return the phosphorus to the soil
where it can be used again.
CAQ 4

29. The diagram shows how carbon cycles through the environment.
Chapter 2
Principles of Ecology
Chapter Assessment Questions
The diagram shows
how carbon cycles
through the
environment.
Describe how
photosynthesis is
involved in the
carbon cycle.
CAQ 5

30. Answer: During photosynthesis, green plants and algae convert carbon
Chapter 2
Principles of Ecology
Chapter Assessment Questions
Answer: During photosynthesis, green
plants and algae convert carbon
dioxide and water to carbohydrates
and release oxygen into the air.
The plants use the carbohydrates
for energy. Carbon dioxide is
released back into the air through
cellular respiration.
CAQ 6

31. Which process returns nitrogen to the food web?
Chapter 2
Principles of Ecology
Standardized Test Practice
Which process returns nitrogen to the food web?
decomposition
denitrification
nitrification
nitrogen fixation D C B A
STP 5