"Plant Life in a CO2-Rich World"
- It has been argued by some that
human-caused increases of the earths atmospheric CO2
is beneficial to the environment (= global ecosystems)
because it will enhance photosynthesis, increasing
productivity, and thus help feed the world. Do you agree
or disagree? Why?
- Guard cells in stomatal complexes
of leaves act as mutisensory regulatory valves. What are
the implications of guard cell response to global
elevations in CO2?
- Often, in the real world,
environmental changes do not occur in isolation, that is
a change in one component is linked to a second component
and so on. Thus, as humans cause an elevation in
atmospheric CO2, a second component is also
changed, for example global warming. How will the combined
effects of elevated CO2 and an attendant
increase in temperature affect the cultivation and
harvest of corn (C4 plant) in Nebraska?
- Why do "short-term
gains" in photosynthesis under elevated CO2
not necessarily translate into "long-term
gains" in photosynthesis?
- Why are C4 plants at a
disadvantage relative to C3 plants with the
predicted increase in global CO2?
- Do stomata tend to close or open
in response to elevated CO2?
- When stomata close, which is
impacted more, CO2 uptake or water loss? Why?
- Is CO2 the most
limiting factor to luxurious plant growth or are
nutrients and water also a factor? Which are the most
- How will the following respond to
an increase in atmospheric CO2? Plant
biodiversity; Plant extinction; Plant community
structure; Weedy plant species ; Nitrogen content of
leaves; Insect consumption of leaves; Predators of
- Will increased plant growths in
response to elevated CO2compensate for the CO2
increase? That is, will the increased growth, enhance
photosynthesis resulting in an increased carbon sink to
balance the source (burning of fossil fuels and
- How will an increase in CO2
plus and increase in temperature in tundra potentially
aggravate the rise of atmospheric CO2? (Hint:
consider the permafrost and decomposition rates in tundra