Energy and Nutrient Flows in Ecosystems

I found this presentation while looking through some stuff over at Slideshare.net, which is a pretty good resource for school notes if you haven’t found it yet. The teacher for this class includes almost everything that we need to know about the differences between the movement of energy and nutrients through and within ecosystems, respectively.

The key points I want you to remember about this topic are as follows:

1. Energy enters, flows through, and leaves a system.
2. Nutrients cycle repeatedly within the system.
3. Most of the energy at any trophic level is lost before it can be used by the next trophic level.
4. Energy is lost 3 main ways:
   • heat
   • waste (feces and tissue loss)
   • used for respiration

The video below is also fairly helpful. What I like about it is the blank energy and nutrient diagram he fills in as he moves through the ecosystem. It’s a nice approach to a possible future test question (hint, hint).