Final Exam Class 5 Flashcards

1
Q

community structue

A

describes the composition of communities

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what are the components of community structure

A

number of species
abundance of species
interactions among species
biotic and abiotic factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

species richness describes

A

the number of species in a community

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

species diversity accounts for

A

number of species and abundance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

frederick Clements argues

A

communities are stable and the result of extensive biotic interactions and coevolution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

(clements) after disturbance species in an area should reach

A

climax community which is stable and predictable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

henry gleason argues

A

comunities are dynamic and are the result of historical chance and abiotic factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

(gleason) unpredictiable

A

communities are ephermeral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

how did gleason and clements test their theories?

A

experimental ponds were built and allowed species to establish themselves over 1 year

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

which theory (clements or gleason) was correct?

A

both Gleason and clements (different species colonized different ponds therefore communities are unpredictable, but most of the species occurred in all 12 ponds)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is a keystone species?

A

have a disproportionately large effect on their surrounding ecosystem relative to its own abundance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is a dominant species

A

can have strong effect just due to high abundance and biomass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is an example of a keystone species

A

sea otters, starfish
- starfish preys on mollusks and mussles which it competes for space, so when you remove the starfish the mussels just take over which throws the species abundances out of whack

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

the presence of a keystone species can limit

A

one species from dominating and promoting community diversity
their removal can change communities

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

all communities face

A

disturbances

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is a disturbance

A

anything that changes the community structure

17
Q

what influences the diversity and ability of organisms adapt to changes?

A

frequency, duration, and predictablility or disturbances

18
Q

whar are the diffeerent types of predictivablity

A

daily : tides
seasonal : winter snow monsoons
aseasonal:froughts, forest fires
millennial: volcanoes and earthquakes

19
Q

what is successsion?

A

the pattern of recovery
-bare rock to lichen moss to annual herb to perennial herb to scrub to forest (climax community)

20
Q

what is primary succession?

A

when a disurbance removes all organisms in an area and the soil
-caused by glaciers or volcanoes (takes hundreds of years)
-pioneer species to intermediate species to climax community

21
Q

the sequence of succession depends on

A

the species involved
their interactions
environmental circumstances
disturbance frequency

22
Q

early species tent o be

A

r selected (weeds)

23
Q

later species tend to be

A

k selected

24
Q

early species interact with subsequent species 3 different ways

A

facilitaiton
toerace
inhibition

25
facilitation
makes conditions avorable for new species
26
tolerace
does not positively ornegatively affect new species
27
inhibition
prevents the establishment of a new species
28
exampes of facilitation
protection from the win increase soil moisture increase available nutrients and organic matter
29
examples of inhibition
limit sunlight compete for nutrients allelochemicals to inhibit growth
30
what is secondary succession?
occurs when a disturbance remove's some but not all organisms in an area
31
secodary sucession is caused by
fires r storms and recovery can take only a hundred or so years - can be important to regulate environments and communities
32
many communities are adapted to
specific disturbance regimes and altering these regimes may negatively impact community structure
33
in the early 1910's
the us forest service began supressing natural forest fires this reduced frequency of secondary succession that was important for communities adapted to periodic disturbances
34