CVJI 8.doc

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Question 1 of 20
The largest reservoir of phosphorus in most ecosystems is phosphorus:
A. in the atmosphere.
B. dissolved in water.
C. in rocks and sediments.
D. bound in animal tissues.
Question 2 of 20
“Nitrogen fixation” refers to the conversion of:
A. carbon compounds to nitrogen compounds.
B. nitrogen gas (N2) to ammonia (NH2).
C. ammonia (NH3) to nitrogen gas (N2).
D. ammonium (NH4+) to nitrate (NO3-).
Question 3 of 20
“Nitrification” is the conversion of:
A. carbon compounds to nitrogen compounds.
B. nitrogen gas (N2) to ammonia (NH2).
C. ammonia (NH3) to nitrogen gas (N2).
D. ammonium (NH4+) to nitrate (NO3-).
Question 4 of 20
A major perturbation of the carbon cycle by human activity is associated with:
A. release of carbon from carbonate rocks.
B. release of carbon from fossil fuel deposits.
C. removal of carbon from the atmosphere in the industrial production of fertilizers.
D. accelerated removal of carbon from the atmosphere by forests.
Question 5 of 20
In aquatic ecosystems, leaves with high lignin content decompose:
A. rapidly because lignin is a nutrient-rich compound.
B. rapidly because lignin enhances colonization by decomposing fungi.
C. slowly because lignin reduces colonization by decomposing fungi.
D. slowly because lignin is a carbon-poor compound.
Question 6 of 20
In aquatic ecosystems, the major agents of decomposition are:
A. aquatic fungi.
B. bacteria.
C. algae.
D. detritivorous fish.
Question 7 of 20
Clearcutting at Hubbard Brook Experimental Forest sharply:
A. increased export of nitrate (NO3-) in stream water.
B. decreased export of nitrate (NO3-) in stream water.
C. increased rates of denitrification in soils.
D. decreased deposition of ammonia (NH3) from the atmosphere.
Question 8 of 20
In Judy Meyer and Gene Likens’ study of phosphorus in Bear Brook:
A. most phosphorus inputs occurred during spring snowmelt.
B. phosphorus inputs were nearly constant over the year.
C. most phosphorus losses occurred during autumn leaf fall.
D. most phosphorus losses occurred during storms and snowmelt.
Question 9 of 20
Fungi and bacteria release nitrogen stored in dead tissue through a decomposition process called:
A. nitrogen fixation.
B. ammonification.
C. denitrification.
D. nitrification.
Question 10 of 20
Nitrate is converted to molecular nitrogen, N2, in a process called:
A. nitrogen fixation.
B. ammonification.
C. denitrification.
D. nitrification.
Question 11 of 20
In stream ecosystems, nutrient retentiveness is:
A. not related to spiraling length.
B. positively related to spiraling length.
C. inversely related to spiraling length.
D. a logarithmic function of spiraling length.
Question 12 of 20
“Primary” succession is succession that:
A. involves establishment of primary producers where there were none.
B. leads to establishment of a climax community dominated by primary producers.
C. occurs on newly exposed geologic substrates, not organic soil.
D. occurs where organic soils have been exposed but not destroyed by disturbance.
Question 13 of 20
The pioneer species at Glacier Bay, Alaska include:
A. mosses.
B. Dryas.
C. alders.
D. horsetails.
Question 14 of 20
During primary succession at Glacier Bay, overall plant species diversity:
A. first increases rapidly, then levels off.
B. increases steadily throughout succession.
C. increases slowly at first, then more rapidly after a few hundred years.
D. peaks at intermediate successional stages.
Question 15 of 20
How does canopy shading influence succession of pines and deciduous trees in the Piedmont of North Carolina?
A. Canopy shading by deciduous trees is required for growth of pines.
B. Canopy shading by deciduous trees prevents establishment of pines until late in succession.
C. Canopy shading by deciduous trees prevents persistence of pines in late successional stages.
D. Canopy shading by pines prevents establishment of deciduous trees.
Question 16 of 20
During succession in Arizona streams, nitrogen retention:
A. increases at first, but then declines late in succession.
B. increases steadily through succession.
C. increases slowly at first, but then rapidly late in succession.
D. increases rapidly at first, then plateaus late in succession.
Question 17 of 20
According to the “facilitation” hypothesis, pioneer species modify the environment in ways that:
A. make it more suitable for their own survival, and less suitable for other species.
B. make it less suitable for their own survival, but more suitable for survival of other pioneer species.
C. make it less suitable for their own survival, but more suitable for survival of late-successional species.
D. make it less suitable for survival of all species.
Question 18 of 20
According to the “inhibition” hypothesis, pioneer species modify the environment in ways that:
A. make it less suitable for other species.
B. make it less suitable for their own survival, but more suitable for survival of other pioneer species.
C. make it less suitable for their own survival, but more suitable for survival of late-successional species.
D. make it more suitable for survival of all species.
Question 19 of 20
The change in plant, animal, and microbial communities in an area following disturbance or the creation of new substrate is called:
A. progression.
B. succession.
C. replacement.
D. colonization
Question 20 of 20
According to the tolerance model of succession:
A. early successional species modify the environment making it less suitable for the establishment by all species.
B. early successional species modify the environment making it less suitable for early successional species, but neither less nor more favorable for late successional species.
C. early successional species modify the environment making it less suitable for early successional species, but more suitable for late successional species.
D. only early successional species can establish as succession begins.