Ecology: Community Eco Flashcards Preview

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Flashcards in Ecology: Community Eco Deck (30)
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2
Q

Individualistic hypothesis

A

Communities assemble by chance of species with similar abiotic requirements

3
Q

Interactive hypothesis

A

Communities assemble by chance of closely linked species

4
Q

Tropic levels are defined by

A

The number of steps though which energy passes to reach organisms in it

5
Q

List basic steps of trophic levels

A

Primary producer-autotrophsPrimary consumersSecondary consumersTertiaryQuaternary

6
Q

Ecological pyramid measures

A

Biomass- measure of weight of tissues

7
Q

Energy pyramid describes

A

The transfer of energy between trophic levels. Only 10% gets consumed from lv to lv

8
Q

Top-down effect

A

Abundance of lower trophic levels depends on consumers

9
Q

Bottom-up effect

A

Abundance of higher levels depends on lower lvs/ producers

10
Q

Trophic cascade

A

When a level is changed (ex population) it sends a cascade of effects trough the chain (usually alternating in increasing/decreasing of other levels)

11
Q

Species richness

A

Number of (different) species in a community

12
Q

Species evenness

A

The relative abundance of species (to each other) in a community

13
Q

Species diversity =

A

Sp evenness + sp richness

14
Q

For any given sp richness, diversity (H) increases with

A

Species evenness and vice versa

15
Q

Communities with very high or low disturbance have _____ species diversity than communities with moderate disturbance

A

Lower

16
Q

Good colonizers are

A

R-selected

17
Q

Good competitors

A

K-selected

18
Q

Species diversity is highest here disturbance is moderate because

A

It allows both colonizers and competitors to coexist (K+r)

19
Q

Good competitors (K) reside on the _____ side of the curve

A

Left side

20
Q

Colonizers (r) reside alone on the ______ side of the curve

A

Right

21
Q

Communities are adapted to a specific frequency and intensity of disturbance.

A

True, ex: adaptations to moderate fires

22
Q

Diversity-stability hypothesis

A
  1. Disturbances in diverse communities is dampened by large # of interactions2. The effect of disturbance is less than it would be in a species community without diversity
23
Q

Succession

A

Transition in species composition over time

24
Q

Primary succession

A

Bare soil, no organisms

25
Q

Secondary succession

A

Organisms present with soil

26
Q

Successional pathway

A

Good colonizers exist earlyGood competitors exist later (near K)

27
Q

Directional succession

A

Progressive change in species comp

28
Q

Cyclical succession

A

Change which in the end results in the original community

29
Q

Invasive species

A

Species that disrupt communities and suddenly become the dominant species.Changes ecosystem structure and function

30
Q

Invasive species means that it is non-native

A

False

31
Q

Environmental disturbance promotes ______ which can alter ______ and promote even ___-

A

Biological invasionMore invasion