Deck 20: Succession and Stability

Question 1

Which statement about ecosystem properties in Sycamore Creek, Arizona after flooding is false?

A) Algal biomass initially increased, then leveled off.
B) Total ecosystem respiration initially increased, then leveled off.
C) Gross primary production initially increased, then leveled off.
D) Nitrogen retention initially increased, then leveled off.

Answer 1

D

Question 2

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.
E) decreases steadily throughout succession.

Answer 2

A

Question 3

"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.
E) occurs after fire or agricultural abandonment.

Answer 3

C

Question 4

As Hawaiian lava flows age over 4 million years,

A) total soil phosphorous levels decrease.
B) total soil phosphorous levels increase.
C) total soil phosphorous stays about the same, but more phosphorous becomes refractory.
D) total soil phosphorous stays about the same, but more phosphorous becomes weatherable.
E) phosphorous limitation of primary production becomes less important.

Question 5

In the area of Glacier Bay, Alaska, the climax community is

A) hemlock forest.
B) muskeg.
C) hemlock forest on steep slopes and muskeg on shallower slopes.
D) hemlock forest on shallow slopes and muskeg on steeper slopes.
E) Dryas mats with scattered alders and cottonwoods.

Question 6

On intertidal boulders in California, the diversity of diatoms and algae

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.
E) first decreases, but later increases.

Question 7

Wayne Sousa's studies of succession on intertidal boulders demonstrated which elements of the inhibition hypothesis?

A) Inhibition of mid- and late-successional species by pioneers
B) Inhibition of late-successional species by mid-successional ones
C) Higher mortality of pioneer species
D) All of the choices are correct.
E) None of the choices are correct.

Question 8

Succession in old fields in the Piedmont of North Carolina involves succession driven

A) largely by facilitation.
B) largely by inhibition.
C) largely by tolerance.
D) both by inhibition and by tolerance.
E) both by facilitation and by inhibition.

Question 9

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
E) invasion

Question 10

In the Piedmont of North Carolina, as plant diversity increases through secondary succession, bird diversity

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.
E) first decreases, but later increases.

Question 11

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.
E) Canopy shading by pines kills deciduous trees that were established early in succession.

Question 12

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.
E) in this model, pioneer species do not modify the environment.

Question 13

During primary succession at Glacier Bay, species diversity continues to increase throughout succession for which group(s) of plants?

A) Tall shrubs and trees
B) Low shrubs and herbs
C) Mosses
D) Lichens
E) All groups of plants

Question 14

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.
E) make it more suitable for survival of all species.

Question 15

During succession in Hawaiian Island forest ecosystems, nitrogen retention

A) increases for the first 20,000 years, then declines.
B) increases steadily through succession.
C) increases for the first 2,000 years, then declines.
D) decreases steadily through succession.
E) decreases for the first 2,000 years, then increases.

Question 16

In secondary succession on abandoned fields in the Piedmont of North Carolina, important pioneer species include

A) horsetails.
B) Dryas.
C) broomsedge (Andropogon).
D) pine seedlings.
E) crabgrass and horseweed.

Question 17

________ occurs in areas where disturbance destroyed the previous community without destroying the soil.

A) Pioneer succession
B) Climax succession
C) Secondary succession
D) Primary succession
E) Disturbance succession

Question 18

The pioneer species at Glacier Bay, Alaska include

A) mosses.
B) Dryas.
C) alders.
D) horsetails.
E) hemlocks.

Question 19

High nitrogen retention early in stream succession is probably due to

A) nitrogen fixation by aquatic fungi.
B) increasing biomass of algal and animal populations.
C) increasing nitrogen inputs from surrounding terrestrial soils.
D) increasing binding of nitrogen to developing organic sediments.
E) reduced denitrification following disturbance.

Question 20

Pine communities are eventually replaced by oak-hickory communities after about 150 years of old field succession on the Piedmont Plateau of North Carolina because

A) mature pines are susceptible to a fungal disease called pine blight.
B) juvenile pines are susceptible to a fungal disease called pine blight.
C) juvenile pines cannot grow in the low pH soil that results as pine litter decomposes.
D) juvenile pines cannot grow in the shade of mature pines.
E) mature pines require an association with mycorrhizal fungi which are excluded from this area by low pH soils.

Question 21

During the first 200 years of succession, total soil depth increased significantly from the pioneer community to the spruce stage, while organic layer depth remained approximately stable.

Question 22

The first plants in a successional sequence are called the ________.

Question 23

What result(s) from the Park Grass Experiment support the idea of community stability? (Select all that apply.)

A) Virtually no new species have been added to the plant community since 1862.
B) The proportions of three plant groups (legumes, grasses, and other species) remained fairly stable over the interval of the study.
C) The proportion of grasses, legumes, and other plants in the study plots varied from year to year, mainly in response to variation in precipitation.
D) The application of fertilizer produced significantly different proportions of grasses, legumes, and other plant species.

Question 24

You are restoring a previously farmed area to the historic prairie community. You add seeds of pioneer species that are known to fix nitrogen. You then place enclosures over your seeded areas. The enclosures allow light and water to reach the seedlings, but keep insects, mammals, and birds out. What successional factor(s) have you managed with your actions? (Select all that apply.)

A) Physical and chemical stressors
B) Plant dispersal rates
C) Plant establishment
D) Interspecific plant interactions
E) Herbivore

Question 25

What statement about geologic features and community resilience in Sycamore Creek is correct?

A) In areas where bedrock lies close to the surface, the algal community is more resilient than in areas where bedrock is farther from the surface.
B) In areas where bedrock lies close to the surface, the algal community is less resilient than in areas where bedrock is farther from the surface.
C) In areas where bedrock is close to the surface, nitrate concentration is lower than in areas where bedrock is farther from the surface.
D) In areas where bedrock is close to the surface, the rate of algal biomass accumulation is lower than in areas where bedrock is farther from the surface.

Question 26

Match the level of taxonomic resolution with the result it supports in the Park Grass Experiment.

A) Not stable
B) Stable
C) Absolutely stable
Individual plant species

Question 27

Match the level of taxonomic resolution with the result it supports in the Park Grass Experiment.

A) Not stable
B) Stable
C) Absolutely stable
Plant groups

Question 28

A community in which secondary succession is very rapid has

A) high resistance.
B) low resistance.
C) high resilience.
D) low resilience.
E) high replication.

Question 29

A tendency for a community to maintain its structure even when subject to potential disturbance is called ________.

Question 30

________ is the ability of a community or ecosystem to maintain structure in the face of potential disturbance.

A) Resilience
B) Elasticity
C) Resistance
D) Plasticity
E) Flexibility

Question 31

What conclusion is supported by the research of Lloyd, Lohse, and Ferré on logging road restoration? data from Lloyd, Lohse, and Ferré 2013

A) Abandoned logging roads will eventually return to the pre-disturbance ecosystem.
B) Within approximately 10 years, recontoured logging roads will have returned to the pre-disturbance ecosystem.
C) Recontouring logging roads is more likely to restore the pre-disturbance ecosystem than abandoning them.
D) Within approximately 10 years, recontoured logging roads will have similar vegetation to areas that never had roads.

Question 32

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) only early successional species can establish as succession begins.
C) early successional species modify the environment making it less suitable for early successional species but more suitable for late successional species.
D) early successional species modify the environment making it less suitable for early successional species but neither less nor more favorable for late successional species.
E) both early successional species modify the environment making it less suitable for early successional species but neither less nor more favorable for late successional species and only early successional species can establish as succession begins.

Question 33

Match the level of taxonomic resolution with the result it supports in the Park Grass Experiment.

A) Not stable
B) Stable
C) Absolutely stable
Whole plant community

Question 34

A set of sites differing in successional age is called a ________.

Question 35

Primary forest succession at Glacier Bay, Alaska can be measured in ________, while secondary forest succession on the Piedmont Plateau, North Carolina can be measured in ________.

A) centuries; decades
B) decades; centuries
C) decades; millennia
D) centuries; millennia

Question 36

What was the effect of adding fertilizer to plots in the Park Grass experiment?

A) Legumes and grasses increased while other plant species decreased.
B) Grasses and other plant species increased while legumes decreased.
C) Legumes and other plant species decreased while grasses increased.
D) Legumes and other plant species increased while grasses decreased.
E) Grasses and legumes species decreased while legumes increased.

Question 37

On intertidal boulders in California, the climax community is dominated by perennial red algae.

Question 38

The mechanisms of facilitation and inhibition alternate during the four stages of succession (pioneer, Dryas, Alder, and Spruce) in Glacier Bay, Alaska.

Question 39

Research by Dias on a former bauxite mine showed that plots that were seeded with preferred plant species had a higher mean seedling density than control plots.