Chapter 55

1.
2.
3.
4.
5.
I can explain how energy regulates the amount and sizes of trophic levels.
1.
2.
3.
4.
5.
I can describe the fundamental relationship between autotrophs, heterotrophs and decomposers in an ecosystem.
I can explain how decomposition connects all trophic levels in an ecosystem.
I can explain why the amount of energy used in photosynthesis is so much less than the amount of solar energy that reaches the Earth.
I can summarize the 10% rule.
I can explain why worldwide agriculture could feed more people if all humans consumed only plant material.
I can explain how limiting factors affect ecosystem dynamics.
1.
2.
3.
4.
I can explain how nitrogen and phosphorous limit the structure of an ecosystem.
I can explain how cultural eutrophication can alter freshwater ecosystems.
I can explain how it is that eutrophic bodies of water are both nutrient rich and oxygen poor.
I can use my understanding of photosynthesis to explain how light limits ecosystems.
I can explain how primary productivity impacts the ecosystem structure.
I can describe how to calculate gross and net productivity.
1.
2.
3.
4.
I can compare gross to net productivity
I can explain the influence of cellular respiration on net productivity.
I can design a lab that measures gross and net productivity.
I can explain how nutrients cycle through an ecosystem.
1.
I can describe how water, nitrogen, carbon, and phosphorous cycle.
2.
3.
4.
5.
I can identify the reservoirs of nitrogen, phosphorous and carbon.
I can describe how living organisms assimilate and release the different nutrients in each cycle.
I can explain the role of bacteria in the nitrogen cycle.
I can explain how the phosphorous cycle is local.
I can describe the role of photosynthesis, and cellular respiration in the carbon cycle.


Trophic efficiencies:10% rule
◦ Generally, only 10% of energy is transferred between trophic levels
◦ Remaining 90% is lost as heat from metabolism

1.
2.
3.
4.
5.
I can explain how energy regulates the amount and sizes of trophic levels.
1.
2.
3.
4.
5.
I can describe the fundamental relationship between autotrophs, heterotrophs and decomposers in an ecosystem.
I can explain how decomposition connects all trophic levels in an ecosystem.
I can explain why the amount of energy used in photosynthesis is so much less than the amount of solar energy that reaches the Earth.
I can summarize the 10% rule.
I can explain why worldwide agriculture could feed more people if all humans consumed only plant material.
I can explain how limiting factors affect ecosystem dynamics.
1.
2.
3.
4.
I can explain how nitrogen and phosphorous limit the structure of an ecosystem.
I can explain how cultural eutrophication can alter freshwater ecosystems.
I can explain how it is that eutrophic bodies of water are both nutrient rich and oxygen poor.
I can use my understanding of photosynthesis to explain how light limits ecosystems.
I can explain how primary productivity impacts the ecosystem structure.
I can describe how to calculate gross and net productivity.
1.
2.
3.
4.
I can compare gross to net productivity
I can explain the influence of cellular respiration on net productivity.
I can design a lab that measures gross and net productivity.
I can explain how nutrients cycle through an ecosystem.
1.
I can describe how water, nitrogen, carbon, and phosphorous cycle.
2.
3.
4.
5.
I can identify the reservoirs of nitrogen, phosphorous and carbon.
I can describe how living organisms assimilate and release the different nutrients in each cycle.
I can explain the role of bacteria in the nitrogen cycle.
I can explain how the phosphorous cycle is local.
I can describe the role of photosynthesis, and cellular respiration in the carbon cycle.



If there is not enough of a resource available, the organisms in the ecosystem are impacted
◦ Nitrogen, phosphorus deficiencies
◦ Used by plants in photosynthesis
◦ Reduced PS = reduced plants = reduced animals
If there is too much of a resource available, the organisms in the ecosystem are impacted
◦ Eutrophication – addition of sewage, fertilizer run off to aquatic ecosystems
◦ Boom in algae, cyanobacteria = less dissolved oxygen for other organisms (fish) = death of fish

1.
2.
3.
4.
5.
I can explain how energy regulates the amount and sizes of trophic levels.
1.
2.
3.
4.
5.
I can describe the fundamental relationship between autotrophs, heterotrophs and decomposers in an ecosystem.
I can explain how decomposition connects all trophic levels in an ecosystem.
I can explain why the amount of energy used in photosynthesis is so much less than the amount of solar energy that reaches the Earth.
I can summarize the 10% rule.
I can explain why worldwide agriculture could feed more people if all humans consumed only plant material.
I can explain how limiting factors affect ecosystem dynamics.
1.
2.
3.
4.
I can explain how nitrogen and phosphorous limit the structure of an ecosystem.
I can explain how cultural eutrophication can alter freshwater ecosystems.
I can explain how it is that eutrophic bodies of water are both nutrient rich and oxygen poor.
I can use my understanding of photosynthesis to explain how light limits ecosystems.
I can explain how primary productivity impacts the ecosystem structure.
I can describe how to calculate gross and net productivity.
1.
2.
3.
4.
I can compare gross to net productivity
I can explain the influence of cellular respiration on net productivity.
I can design a lab that measures gross and net productivity.
I can explain how nutrients cycle through an ecosystem.
1.
I can describe how water, nitrogen, carbon, and phosphorous cycle.
2.
3.
4.
5.
I can identify the reservoirs of nitrogen, phosphorous and carbon.
I can describe how living organisms assimilate and release the different nutrients in each cycle.
I can explain the role of bacteria in the nitrogen cycle.
I can explain how the phosphorous cycle is local.
I can describe the role of photosynthesis, and cellular respiration in the carbon cycle.




Primary productivity
Gross Primary
Productivity
Net Primary
Productivity

Rate at which plants convert sunlight energy into chemical energy

Rate at which plant produces organic material through photosynthesis

Net gain of dried mass stored in plant after respiration

Net
Production
= gross - respiratory production losses
NPP = GPP - R

1.
2.
3.
4.
5.
I can explain how energy regulates the amount and sizes of trophic levels.
1.
2.
3.
4.
5.
I can describe the fundamental relationship between autotrophs, heterotrophs and decomposers in an ecosystem.
I can explain how decomposition connects all trophic levels in an ecosystem.
I can explain why the amount of energy used in photosynthesis is so much less than the amount of solar energy that reaches the Earth.
I can summarize the 10% rule.
I can explain why worldwide agriculture could feed more people if all humans consumed only plant material.
I can explain how limiting factors affect ecosystem dynamics.
1.
2.
3.
4.
I can explain how nitrogen and phosphorous limit the structure of an ecosystem.
I can explain how cultural eutrophication can alter freshwater ecosystems.
I can explain how it is that eutrophic bodies of water are both nutrient rich and oxygen poor.
I can use my understanding of photosynthesis to explain how light limits ecosystems.
I can explain how primary productivity impacts the ecosystem structure.
I can describe how to calculate gross and net productivity.
1.
2.
3.
4.
I can compare gross to net productivity
I can explain the influence of cellular respiration on net productivity.
I can design a lab that measures gross and net productivity.
I can explain how nutrients cycle through an ecosystem.
1.
I can describe how water, nitrogen, carbon, and phosphorous cycle.
2.
3.
4.
5.
I can identify the reservoirs of nitrogen, phosphorous and carbon.
I can describe how living organisms assimilate and release the different nutrients in each cycle.
I can explain the role of bacteria in the nitrogen cycle.
I can explain how the phosphorous cycle is local.
I can describe the role of photosynthesis, and cellular respiration in the carbon cycle.



Biotic factors are made up of matter
(CHNOPS)
This matter cycles in our biosphere






Water cycle
Carbon cycle
Nitrogen cycle
Phosphorus cycle
Nicely reviewed on pages 1228-1229!


Key processes:
◦ Transpiration
 Evaporative loss of water through leaves
◦ Condensation
 Water vapor forms clouds
◦ Precipitation
 Returns water to land


Key processes:
◦ Photosynthesis
 Removes atmospheric
CO
2
◦ Cellular respiration
 Returns CO
2 atmosphere to
◦ Burning of fossil fuels
 Adds significant CO to atmosphere
2


Key processes:
◦ Nitrogen fixation
 Conversion of atmospheric
N
2 to usable forms by bacteria
◦ Ammonification
 Decomposes organic nitrogen to NH
4
+
◦ Nitrification
 NH
4
+ is converted to NO by nitrifying bacteria
3
-
◦ Denitrification
 Anaerobic bacteria convert
NO
3
to N
2


Key processes:
◦ Weathering of rocks
 Adds phosphorus to soil
◦ Uptake by producers
◦ Producers eaten by consumers
◦ Decomposers return phosphorus to soil

1.
2.
3.
4.
5.
I can explain how energy regulates the amount and sizes of trophic levels.
1.
2.
3.
4.
5.
I can describe the fundamental relationship between autotrophs, heterotrophs and decomposers in an ecosystem.
I can explain how decomposition connects all trophic levels in an ecosystem.
I can explain why the amount of energy used in photosynthesis is so much less than the amount of solar energy that reaches the Earth.
I can summarize the 10% rule.
I can explain why worldwide agriculture could feed more people if all humans consumed only plant material.
I can explain how limiting factors affect ecosystem dynamics.
1.
2.
3.
4.
I can explain how nitrogen and phosphorous limit the structure of an ecosystem.
I can explain how cultural eutrophication can alter freshwater ecosystems.
I can explain how it is that eutrophic bodies of water are both nutrient rich and oxygen poor.
I can use my understanding of photosynthesis to explain how light limits ecosystems.
I can explain how primary productivity impacts the ecosystem structure.
I can describe how to calculate gross and net productivity.
1.
2.
3.
4.
I can compare gross to net productivity
I can explain the influence of cellular respiration on net productivity.
I can design a lab that measures gross and net productivity.
I can explain how nutrients cycle through an ecosystem.
1.
I can describe how water, nitrogen, carbon, and phosphorous cycle.
2.
3.
4.
5.
I can identify the reservoirs of nitrogen, phosphorous and carbon.
I can describe how living organisms assimilate and release the different nutrients in each cycle.
I can explain the role of bacteria in the nitrogen cycle.
I can explain how the phosphorous cycle is local.
I can describe the role of photosynthesis, and cellular respiration in the carbon cycle.