The material for this lesson is presented two ways. There is a sample lesson
which your students can use online. You can use the lesson as a guide for your class
discussions. This allows individualization by you and your students. If you want
to use second
approach refer to resources for a collection of the models and data used in the lesson. You can pick
and choose from these tools and other material you find to design your own
lesson.
The lesson is designed as two explorations. The first activity explores the
carbon sequestered by a tree that your students see everyday. Then they relate
the carbon in that tree to carbon dioxide they are responsible for adding to the
atmosphere. Depending on the time you can commit to this activity you can help
the students work through the algorithm used to calculate the carbon in your
tree or you can move straight to the completed model. The computational science
skills involved in this lesson involve learning how to use computer models and
evaluating their output.
In the last few decades computers and computer modeling have had a profound
effect on the science that is being done. Many experiments are so expensive and time consuming that direct experimentation is limited or impractical.
Computer models take the formulas scientists have developed through field
research and allow us to perform hundreds of simulated experiments. This lesson
introduces the students to the new form of science called Computational
Science. In this lesson the students will learn to "mine data"
by looking at tables of numbers and rendering them into graphs in order to see
trends and patterns. This is called visualization. This is the kind of skill
your local weather person uses when he/she explains the weather maps that were
computer generated. Your students will also change the parameters that define
how the forest is managed in order to recommend local and national policy. By
working with professional models on current issues, the students will learn how
scientists work and how science is done.
A note on the formulas used to calculate the carbon in your tree. I am using
formulas derived by foresters to estimate the weight of classes of trees in the
forests of the southeastern US. Similar studies and formulas are available for
trees in different sections of the US and I assume the world. These formulas are
used extensively by the forestry industry to plan where and when to harvest
their forests. The formulas are a best fit for the data and as such, more of an
estimate rather than an exact value. I contacted my county extension agent to
get the formulas. He didn't know the formulas, but he forwarded my request to
foresters in my state who were eager to help me. Most of trees in the studies
were in stands of trees not an isolated tree in a grassy field.
The second part of the lesson looks at the carbon sequestration of a forest
over time. This is provided by a professional model built by a team of Dutch
scientists at the Wageningen University and Research Center, Silviculture and Forest Ecology Group.
The software including input files can be downloaded from the world wide web: http://www.efi.fi/projects/casfor
This is a free down load. They encourage professional and educational use of
the model and their sample forest plots. They require you to request the model
from them so they can document its use.
I have provided a suggested lesson for learning how to mine the data which
this model provides. When you down load the model you will also get a suggested
introduction activity. The model provides one set graph of the data. In order to
see other relationships, copy columns to an Excel spreadsheet and use Excel
to manipulate and graph the data.
This model allows the students to see how a forest's capacity to sequester
carbon changes over time. There are many variables in the model that can be
changed. They range from: how, where and what to plant, how and when to harvest
the trees, what to do with the harvested trees, how to recycle the products,
what happens to recycled products, how many years to run the model. This lesson
only scratches the surface of the model's potential. If you or your students use
the model to develop additional lessons or reports please let me know where you
post them so I can link to your work. If you are unable to find a server to post
your work I would be happy to work with you to find a server to share your
research.
I have provided an answer key to my lessons. The students questions are in red
and suggested answers are blue.
| 
