Ecosystems Lesson 4 Overview


NOTE: This lesson introduces a quantitative model of carbon pools and fluxes, then uses that model to explain how ecosystems change over time. This is challenging content that addresses NGSS High School Performance Expectations. You may want to skip it with middle school classes.

In Lesson 2, students identified the pattern of organic matter distribution (the organic matter pyramid) in a meadow ecosystem. In Lesson 3, they explained why that pattern exists by tracing matter and energy and connecting scales. In Lesson 4, students explain changes in ecosystems by keeping track of carbon pools and carbon fluxes. Carbon fluxes are the rates (mass/time) at which carbon transforming processes occur.

Guiding Question

How and why do carbon pools in ecosystems change over time?

Activities in this Lesson

  • Activity 4.1: Tiny Pool and Flux Game (30 min)
  • Activity 4.2: Carbon Pools and Constant Flux Simulation (30 min)
  • Activity 4.3: How Fluxes Change and Photosynthesis Limits (40 min)
  • Activity 4.4: Seasonal Changes and Ecosystem Disturbances (40 min)

Unit Map

Ecosystems Unit Map