Forest Mensuration Final Exam Questions
and Answers 100% Solved
What is simple linear regression used for? Used to relate one dependent variable to a
single dependent variable.
3 reasons for measuring biomass? 1) To understand how tree growth occurs
2) Help us determine how much carbon is sequestered by forests
3) Some forest products are sold by weight (not volume)
What wood products are sold by weight not volume? 1) Short rotation forests used for
bioenergy
2) Firewood
3) Wood used for paper making
How do we measure tree biomass? Involves felling, dissecting, drying, then weighing
tree components. Plants can be dried at 60-80 degrees C for several days
,How do we measure branch and foliage biomass? 1) Count all branches that emerge from
trunk of tree and select a random sample from this total. Remove all leaves, cut branches into
even-sized sections and dry
2) Use regression analysis to estimate foliage and branch dry weight from branch diameter
and/or length
How do we calculate stem biomass? Determine sectional volume of whole tree and
convert volume to biomass based on wood density.
-Determine wood density by taking sample discs along entire length of stem and measuring their
volume. Discs are then dried and weighed.
Root biomass sampling techniques? 1) Physical excavation of entire root system
2) Soil cores-take soil core samples throughout growing season to determine growth rate of fine
roots
3)Ingrowth cores-use mesh sleeve containing root free soil and insert into hole left by soil core
4) Minirhizotrons- transparent tubes inserted into ground that contain cameras which record fine
root growth
How can we estimate carbon content of biomass? For trees, carbon can generally be
estimated as 50% of total biomass
, What are allometric functions in regards to tree biomass? Biomass functions designed to
estimate the biomass of various parts of a tree from simpe measurements such as DBH
How can we estimate leaf biomass? Leaf biomass tends to increase rapidly at first then
plateau. Width of sapwood has been good predictor of foliage biomass
What is a forest stand? A more or less homogeneous patch of forest
*Varies depending on terrain, species, person determining boundaries
Why do we measure stands? To know how much timber or other forest products are
available.
-Helps determine total value of landscape.
How do we measure entire stands? Could measure all trees but not time or cost efficient.
-Scale up, determine suitable number of plots to adequately describe stand
and Answers 100% Solved
What is simple linear regression used for? Used to relate one dependent variable to a
single dependent variable.
3 reasons for measuring biomass? 1) To understand how tree growth occurs
2) Help us determine how much carbon is sequestered by forests
3) Some forest products are sold by weight (not volume)
What wood products are sold by weight not volume? 1) Short rotation forests used for
bioenergy
2) Firewood
3) Wood used for paper making
How do we measure tree biomass? Involves felling, dissecting, drying, then weighing
tree components. Plants can be dried at 60-80 degrees C for several days
,How do we measure branch and foliage biomass? 1) Count all branches that emerge from
trunk of tree and select a random sample from this total. Remove all leaves, cut branches into
even-sized sections and dry
2) Use regression analysis to estimate foliage and branch dry weight from branch diameter
and/or length
How do we calculate stem biomass? Determine sectional volume of whole tree and
convert volume to biomass based on wood density.
-Determine wood density by taking sample discs along entire length of stem and measuring their
volume. Discs are then dried and weighed.
Root biomass sampling techniques? 1) Physical excavation of entire root system
2) Soil cores-take soil core samples throughout growing season to determine growth rate of fine
roots
3)Ingrowth cores-use mesh sleeve containing root free soil and insert into hole left by soil core
4) Minirhizotrons- transparent tubes inserted into ground that contain cameras which record fine
root growth
How can we estimate carbon content of biomass? For trees, carbon can generally be
estimated as 50% of total biomass
, What are allometric functions in regards to tree biomass? Biomass functions designed to
estimate the biomass of various parts of a tree from simpe measurements such as DBH
How can we estimate leaf biomass? Leaf biomass tends to increase rapidly at first then
plateau. Width of sapwood has been good predictor of foliage biomass
What is a forest stand? A more or less homogeneous patch of forest
*Varies depending on terrain, species, person determining boundaries
Why do we measure stands? To know how much timber or other forest products are
available.
-Helps determine total value of landscape.
How do we measure entire stands? Could measure all trees but not time or cost efficient.
-Scale up, determine suitable number of plots to adequately describe stand
