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Chapter 3: Ecosystem Ecology - Lesson 2: Movement of Matter

Chapter 3: Ecosystem Ecology - Lesson 2: Movement of Matter


Describe how carbon, nitrogen, and phosphorus cycle within ecosystems.

In the carbon cycle, producers take up CO2 for photosynthesis and transfer the carbon to consumers and decomposers.  Some of this carbon is converted back into CO2 by respiration, while the rest is lost to sedimentation and burial.  The extraction and combustion of fossil fuels, as well as the destruction of forests, returns CO2 to the atmosphere.  The nitrogen cycle has many steps.  Nitrogen is fixed by organisms, lightning, or human activities, then assimilated by organisms.  Ammonium is released during decomposition of dead organisms and wastes.  Finally, denitrification returns nitrogen to the atmosphere.  The phosphorus cycle involves a large pool of phosphorus in rock that can be made available to organisms either by leaching or by mining.  Organisms then assimilate it and ultimately transfer it back to the soil via excretion and decomposition.

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Chapter 3 Lesson 2 Sticky Note Video

Watch this video, and complete your sticky notes and WSQ Form and be ready for a quiz tomorrow! :)

What's the Deal with Carbon?

This animation describes the carbon cycle and how it is affected by human activity. It was featured in the Sustainable Shelters exhibit at the Bell Museum of Natural History at the University of Minnesota.


Nitrogen is the important essential element for all living organisms by the synthesis of amino acids, proteins, Enzymes, etc. What happens if there is no Nitrogen? Root systems and plant growth are stunted. Older leaves turn yellow. Decrease in crop production. Soil microorganisms life become dangerous. In the atmosphere its concentration is 78 percent.

The Phosphorus Cycle in 65 Seconds

Do you only have "about a minute" to learn about the phosphorous cycle? Here it is...quick and simple.

Battling the Bloom: Lake Erie

Millions depend on Lake Erie for drinking water and recreation. It's also a vital fishery. But it has a long history of environmental damage, and that continues today with a resurgence of toxic algal blooms. Farmers are teaming up with researchers to try and understand why agriculture is now the leading cause of Lake Erie's recent algal blooms and what can be done to fix it.

Chapter 3 Lesson 2 WSQ

Complete this WSQ after you watch Mrs. Schaelling's Chapter 3 Lesson 2 Video. This should be done before you come to class.

DOK Question Stems

Try to create most of your questions at a DOK Level 2 or 3. That way you're challenging your thinking.