Unit A

Module 2 ~ Lesson 1


  Ecosystem Productivity


University of Michigan. Used under the Fair Dealings clause of the Canadian Copyright Act. https://globalchange.umich.edu/globalchange1/current/lectures/kling/energyflow/energyflow.html


Productivity is the rate at which organisms produce new biomass

Productivity for different ecosystems varies greatly


Productivity is a measure of the energy trapped by photosynthesis in a given area over a specified interval. To measure productivity, scientists calculate the total change in plant biomass in an area per year. Knowing that one gram of plant material yields about 20 J of energy, they can then calculate the energy that was captured and stored. Productivity is generally expressed in kJ/m2/year.      

As you can see from the image above, productivity can vary greatly depending on the ecosystem. The factors that most impact productivity are average temperature, amount of incoming solar radiation, availability of nutrients, and total moisture (for a terrestrial ecosystem).  

UV radiation.


Ultraviolet radiation (UVR) is one type of energy in sunlight. UVR can be harmful to cells as it can damage their DNA. Many organisms have adapted to protect themselves from DNA damage. Additionally, ozone in the upper atmosphere absorbs UVR, preventing it from reaching the surface.

  Read

Read "The Balance of the Matter and Energy Exchange" on pages 53 to 55 in your textbook.


Watch

Indigenous culture in Canada has a very different perspective on land use than modern Candian culture. Watch the video to hear more about Indigenous perspectives.
 

Read


Read "Preserving the Natural Balance" and "Far-Reaching Consequences" on pages 59 to 60 of your textbook.