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Geog. 4371
Fall 2005
Quiz (50 pts)
1. List the 5 factors of the operational environment that are mainly associated
with climate. 5 pts.
1. Solar radiation
2. Air temperature
3. Atmospheric gases and particulate matter
4. Atmospheric humidity
5. Mechanical force (for example, wind)*
2. List the 4 factors of the operational environment that are mainly associated
with soil. 4 pts.
1. Soil moisture available to plant roots
2. Soil temperature
3. Soil chemicals in liquid and solid phases
4. Soil gases
3. List the 4 biotic factors of the operational environment. 4 pts.
1. Symbionts
2. Pathogens
3. Herbivores
4. Direct human action
4. Define competition in the context of the operational environment. 2 pts.
Competition is the modification on one plant’s operational environment by a second
plant so that the operational environment becomes less favorable to the growth,
survival, and/or reproduction of a second plant.
5. Define symbiont in the context of the operational environment. 2 pts.
Symbiont is any organism, on which a plant depends for its dispersal, germination,
survival, growth, or reproduction.
6. Define ecotype and list the 5 key aspects of the concept. 6 pts.
An ecotype is a population distinguished by morphological and/or physiological
characteristics, interfertile with other ecotypes of the same species, but usually
prevented from naturally interbreeding by ecological barriers. It is a subpopulation of a
species, which is genetically differentiated so that its survival in a particular habitat is
enhanced.
1. differences are genetically based;
2. differences may be morphological, physiological or phenological;
3. ecotypes occur in distinct habitats;
4. the genetic differences are "adaptive" (i.e. enhance survival and reproduction
in that particular habitat);
5. ecotypes are potentially interfertile
7. Briefly define “habitat-type” as used in the classification developed by R.
Daubenmire which is so widely used by land-management agencies in the
western U.S? 2 pts.
A physical environment or parts of the (forested) landscapes that will support particular
“climax” (or late successional) plant associations in the absence of disturbance.
8. What is the difference between a “shelterwood” and a “seed tree method” of
silviculture. 2 pts.
In Silviculture, the main difference between “shelterwood” and the “seed tree method”
methods is:
Shelterwood is a system characterized by the amount or number of tree that
were not cut, which provide both seeds for tree regeneration and also protection
to those regeneration. On the other side, “seed tree method” leaves also trees
(usually at lower densities), which provide seeds for regeneration, but do not
necessarily provide protection for regeneration as the “shelterwood” method
does.
9. Under what circumstances might clearcutting be more appropriate than a
“single-tree selection” method of silviculture. 2 pts.
Under a management goal that involves a even-age and/or ‘shade-intolerant’ species,
whose seedlings will regenerate at best under: a) high intensity light conditions, b) high
temperatures, c) dry soils, d) on a thin or inexistent (bare mineral) soils, etc.
10. Under low light levels, are tree seedlings likely to have higher or lower
shoot/root ratios. 2 pts.
Higher shoot/root ratios
11. What role does winter chilling play in the annual life cycle of a tree? 2 pts.
It induced plants into “true” dormancy, which allows plants to break dormancy in the
spring and grow, and reproduce during the spring and summer.
12. For the same tree species, are sun leaves or shade leaves more likely to have
more palisade cells. 2 pts.
-Sun leaves
13. As atmospheric carbon dioxide decreases, does net photosynthesis tend to
increase or decrease? 1 pt.
-Decreases
14. Why is it important that foresters exercise strict controls on the planting of
different photoperiodic ecotypes? 2 pts.
Since different photoperiodic ecotypes have different requirements in terms of hours of
daylight for triggering phenological processes (the relationship between day length and
dormancy and possible cold damage), planted ecotypes may have unusual growth,
fruiting, and flowering rates, poor survival, low productivity, and in general undesirable
results.
15. Define compensation point as applied to the growth of tree seedlings. 2 pts.
The intensity of PAR at which carbon and energy losses as results of respiration exactly
balance carbon and energy gains by photosynthesis so that tree seedlings do no growth
until PAR intensity is increased.
16. List two examples of the morphological effects of strong winds on trees
(excluding windthrow or treefalls) 2 pts.
-Flagging
-Cushion/shrubby shaped architecture or general appearance
-Dwarfism
-Leaf erratic growth/tattering
-Increase in branch diameter
-Buttresses, etc.
17. How have trenching experiments influenced foresters’ understanding of tree
seedling “shade tolerance”? 2 pts.
It helped them to understand that “shade tolerance” reflect the ability of a given
tree seedling to tolerate low light intensities, but also refers to an ability of those
seedlings to compete for soil resources, such as moisture and nutrients.
TRUE OR FALSE QUESTIONS
18. True or False: In a physiognomic classification of vegetation, the vegetation is
classified primarily by floristic composition (i.e. the list of species present). 2 pts.
Circle:
True
or
False
19. True or False: Clausen, Keck and Hiesey showed that variations in average heights
of yarrow (Achillea) represented ecotypes adapted to environmental conditions along a
transect from coastal California to near treeline in the Sierra Nevada. 2 pts.
Circle:
True
or
False
20. True or False: As long as abundant carbon dioxide is present, availability of
moisture will not influence the photosynthetic rate of a tree? 2 pts.
Circle:
True
or
False
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