The Carbon Stored in a Tree
Yesterday marked a big day for the Green City Partnerships
program and the music scene in the Pacific Northwest.
The press release (and the numerous blogs and other on-line media sources that are populating the web) covers the details of the why, where, when, and how. It’s wonderful to see so much activity and interest in the project!
I still wonder, however, if the supporters and skeptics know about carbon sequestration and why tree planting projects are an important player in storing carbon. How many people know how the carbon ends up in the tree?
A few years ago, a group of filmmakers interviewed students graduating from Harvard and asked them how a tree gets its mass? The answers were comical. Most students mentioned something about photosynthesis, sunlight, water, soil, and carbon dioxide — a good understanding of the different pieces, but not the entire picture.
So, how does a tree get its mass? And, how is it related to carbon sequestration?
Remember back to your high school biology class. Trees and plants absorb carbon dioxide through their leaves during a process called photosynthesis. Sunlight provides the energy that allows the carbon dioxide (CO2) to mix with water (H20) and form the sugars (or carbohydrates) that plants need to thrive and grow, and the oxygen (O2) that is emitted during the process.
Here is the simple chemical equation (there are more complicated equations, but this is the easiest one to use to show the process):
6 CO2 + 6 H2O + sunlight –> C6H12O6 + 6 O2
Part of C6H12O6 (the sugars) link together to form cellulose, which makes up the structure of the tree or plant — the mass! The other sugars provide the energy needed for the tree or plant to grow. Also in the mass of a tree is water — lots of it.
Now, where does that carbon dioxide come from? The simplest answer is the air! So, a tree takes in the carbon dioxide that is floating around in the air, through photosynthesis converts the carbon dioxide to sugars, and produces oxygen that we breathe. Quite remarkable!
When you add the very cool process of photosynthesis with the very cool band Pearl Jam, it makes for a big day!