This page contains the materials used in this lesson. If you click on the
instrument, it downloads to your computer. If you use them in lessons you design
please reference them so other teachers can find the material and mix and match
like you have done.
CO_{2} Calculator This is an Excel
spreadsheet. The spreadsheet calculates a tree's diameter from its
circumference, height from 3 similar triangle measurements, tree's green weight
from height, diameter and tree type, roots weight, total weight, dry tree root
and total weight, carbon in tree root and total tree, CO_{2} in tree root total
tree, equivalent CO_{2} from gasoline, natural gas, electricity or heating oil.
Dry weight  percent moisture comparison. This
is an Excel spreadsheet that compares the dry weight of different kinds of trees
with their percent of moisture. There
isn't an obvious trend. Many questions don't give us the answers we expect.
Since there isn't an obvious pattern, we should ask why not. If trees become
completely saturated with water they sink. The reason they float is that the
heart wood is dead and the cells have "air" in them like balloons. When these
balloons fill with water the log sinks. The percentage of water relates to the
percentage of cells that have water in them and how much water they contain. The
dry weight of a tree is related to the ratio of cell wall to empty space in the
cell. In dry weight the dominant factor seems to be the percentage of cells that
are filled with water. There is a slight trend for heavy trees i.e. trees with
relatively thick cell walls to interior ratios, to have less water. All other
things being equal, that makes sense but most of the time the percentage of
cells that are filled with water is so dominant that the two factors aren't
equal. It is good for students to see that scientific explorations don't
always proceed directly to the expected results. Even unexpected results are opportunities
to gain insight.
CO2FIX V 2.0 This is the professional forest model used in this lesson. It
was produced by
the CASFOR project by G.J. Nabuurs, J.F. GarzaCaligaris, M. Kanninen, T.
Karjalainen, T. Lapvetelainen, J. Liski, O. Masera, G.M.J. Mohren, A. Pussinen, and
M.J. Schelhaas of ALTERRA, UNAM, CATIE and EFI at the Wageningen
University
and
Research
Center
.
The software including input files can be downloaded free from the world wide web:
http://www.efi.fi/projects/casfor
CO2FixWURex1 I transferred the stock and flow
tables from the first sample forest provided with the CO2 Fix model to an Excel
spreadsheet. Your students can analyze the data for this run. They won't be able
to change the variables in the model for a new run.
CO2FIXexharvest is the second sample model
provided with their suggested changes to include harvesting of the forest. The
flow and stock tables are in an Excel spreadsheet.
DGLBeedhComploggmort is a third sample
forest provided with the model. Again, I copied the flow and stock tables to an
Excel spreadsheet. This forest is a Douglas Fir and Beech plot with logging.
Tree diameter This is a web page that
contains a JavaScript calculator to calculate a tree's diameter if you input its
circumference.
Tree height This is a web page that
contains a JavaScript calculator to calculate a tree's height using similar
triangles. You input distance to tree, distance from your eye to ruler, and
apparent height of tree against the ruler. The calculator returns an estimate of
the tree's height.
The following links are to web page calculators that return the green weight
for their respective types of trees:
Yellow Poplar
Sweetgum
Soft Hardwood
Hard Hardwood
Southern Pine Coastal
Southern Pine Peidmont
Web page that calculates the dry
weight of a tree based on its green weight and moisture content..
Web page that calculates the carbon
in a tree based on its dry weight.
Web page that calculates the gallons
of gasoline that are equivalent to a tree's carbon.
The following are tables used to calculate the weight and dry weight of
trees:
Table of tree type i.e. pine soft
or hard hardwood
Table with percent water in green
wood and dry/green ratio.
