Science Concepts—Blue Carbon

Summary: This topic guide begins with a review of photosynthesis and progresses to the role marine wetlands play in carbon storage. Through photosynthesis, plants absorb carbon dioxide and release oxygen. Animals, in contrast, breathe in oxygen, and breathe out carbon dioxide. Since the Industrial Revolution, humans have been adding more carbon into the atmosphere through the burning of fossil fuels, and this imbalance in the carbon cycle has led to changes in the Earth’s climate. The role that plants naturally play in carbon uptake is becoming increasingly important as humans look for ways to deal with increasing amounts of carbon in the atmosphere. Plants living in the ocean have a tremendous role to play in carbon storage, and salt marshes are particularly good at storing carbon. Understanding the important role marine wetlands play in carbon sequestration can help humans prioritize wetlands protection and restoration efforts.

Concepts to teach:


  1. Through photosynthesis, plants take in carbon dioxide from the air
  2. Most of a tree’s mass is made up of carbon
  3. Salt marshes store a lot of carbon because the organic material is slow to decompose

Standards: NGSS Performance Expectations

  • MS-LS1-6. Construct a scientific explanation based on evidence for the role of photosynthesis in the cycling of matter and flow of energy into and out of organisms.

Specific Objectives:
Students will be able to:

  1. Articulate an explanation of photosynthesis to describe how plants put on mass
  2. Define Blue Carbon
  3. Describe the role marine wetlands play in storing carbon

Activity Links and Resources:


  • Use Van Helmont’s question as a formative assessment to elicit ideas about how plants put on mass.
  • Redesign Van Helmont’s experiment.
  • Both exercises from the Bringing Wetlands to Market include specific performance tasks that can be assessed