COMMUNITY STRUCTURE

Question 1

Assemblage of interacting populations that occur together in space and time

Answer 1

COMMUNITY

Question 2

COMMUNITY PROPERTIES

Answer 2

COLLECTIVE
EMERGENT

Question 3

The sum of all the properties of populations that make up the community

Answer 3

COLLECTIVE PROPERTIES

Question 4

“More than the sum of its parts”

• Properties that arise only upon assembly of a community
• RESULT FROM the INTERACTION of populations

Answer 4

EMERGENT PROPERTIES

Question 5

EXAMPLES OF COLLECTIVE PROPERTIES

Answer 5

Biomass
Carrying capacity
Dominance
Diversity
Productivity

Question 6

EXAMPLES OF EMERGENT PROPERTIES

Answer 6

Trophic structure (food chains/web)
Stability
Resilience

Question 7

TOTAL number of ORGANISMS in a community

Answer 7

ABUNDANCE

Question 8

NUMBER of SPECIES, ecological NICHES, or GENETIC variations

Answer 8

DIVERSITY

Question 9

RATE of BIOMASS ACCUMULATION; measured in yield or net income

Answer 9

PRODUCTIVITY

Question 10

TYPES OF PRODUCTIVITY

Answer 10

Primary vs. secondary productivity

Gross vs. net primary productivity

Question 11

Number of species at each TROPHIC LEVEL and the number of trophic levels in a community

Answer 11

COMPLEXITY AND CONNECTEDNESS

Question 12

BALANCE of species in the community

Answer 12

EQUITABILITY

Question 13

persistence of a community or an ecosystem in the face of DISTURBANCE

Affected by scale of measurement

Answer 13

STABILITY

Question 14

viability to produce in a LONG TERM BASIS; persistence with stress over the long term

Answer 14

SUSTAINABILITY

Question 15

ability of a community or ecosystem to MAINTAIN structure and/or function in the face of potential disturbance (inertia)

Answer 15

RESISTANCE

Question 16

ability of a community or ecosystem to BOUNCE BACK after a disturbance (renewal)

Answer 16

RESILIENCE

Question 17

COMMUNITY CHARACTERSITICS

Answer 17

ABUNDANCE
COMPLEXITY AND CONNECTEDNESS
DIVERSITY
EQUITABILITY
PRODUCTIVITY
RESISTANCE
RESILIENCE
STABILITY
SUSTAINABILITY

Question 18

basis for RESILIENCE

Answer 18

SUCCESSION

Question 19

Composition, patterns of distribution (temporal or spatial), trophic levels, and their interaction with the environment

Answer 19

COMMUNITY STRUCTURE

Question 20

Attributes of Community Structure:

Answer 20

COMPOSITION
DISTRIBUTION
DIVERSITY

Question 21

COMMUNITY INDICES

Answer 21

DENSITY
DIVERSITY
DOMINANCE
EVENNESS

Question 22

Gives weight on rare species

Answer 22

Shannon Index (Heterogeneity):

Question 23

Only looks into contribution of dominants

Answer 23

Simpson Index (Homogeneity):

Question 24

COMMUNITY STRUCTURE: physical

Answer 24

VERTICAL STRUCTURE
HORIZONTAL STRUCUTRE

Question 25

Determined largely by LIFE FORM of the plants Influences and is influenced by the vertical gradient of light

Answer 25

TERRESTRIAL ; VERTICAL

Question 26

Strata determined by LIGHT PENETRATION and profiles of TEMPERATURE and OXYGEN

Answer 26

AQUATIC ; VERTICAL

Question 27

Size, shape, and dispersion of patches across the landscape (and/or seascape)

Answer 27

HORIZONTAL

Question 28

- Boundary between adjacent habitats - Place where two or more vegetation types meet

Answer 28

EDGE

Question 29

- Tendency for greater variety of organisms in an ecotone - Response of organisms to environmental changes (changes in community structure)

Answer 29

EDGE EFFECT

Question 30

TRANSITION ZONE between two structurally different communities

Answer 30

ECOTONE

Question 31

COMMUNITY STRUCTURE: biological

Answer 31

SPECIES DIVERSITY SPECIES DOMINANCE

Question 32

Richness + Evenness

Answer 32

SPECIES DIVERSITY

Question 33

May be determined by: 1. Most numerous 2. Highest biomass 3. Preempts the most space 4. Makes the largest contribution to ENERGY FLOW and MATERIAL CYCLING 5. Or by some other means controls or INFLUENCES the rest of the community

Answer 33

SPECIES DOMINANCE

Question 34

Species whose activities have a significant role in determining community structure by: 1. Affecting many other organisms 2. Helping to determine the types and numbers of other species in that community

Answer 34

KEYSTONE SPECIES

Question 35

KEYSTONE SPECIES: Term coined by _____ _____ in 1969

Answer 35

ROBERT PAINE

Question 36

KEYSTONE SPECIES: LOW in ______ but LARGE ______ on community structure Presence is _____ to the integrity of the community

Answer 36

BIOMASS ; EFFECT; CRITICAL

Question 37

MODEL OF SPECIES RICHNESS Total range of available resources.

Answer 37

R

Question 38

MODEL OF SPECIES RICHNESS Niche breadth or specialization — how wide a resource range a species uses.

Answer 38

r-bar

Question 39

MODEL OF SPECIES RICHNESS Degree of overlap — how much the resource use of neighboring species overlaps.

Answer 39

o-bar

Question 40

MODEL OF SPECIES RICHNESS Number of species.

Answer 40

n

Question 41

KEYSTONE SPECIES: May be: A ______ (e.g., Banksia prionotes honeyeaters) In any _____ _____ (predator/prey)

Answer 41

MUTUALIST TROPHIC LEVEL

Question 42

Food chains and food webs are adversely affected by:

Answer 42

1. Introduction of exotic and invasive species 2. Removal of a keystone species

Question 43

Food webs in ______ environments tend to have SHORTER food chains with FEWER links than those in more constant environments e.g. Mulawin Creek vs. fishpond

Answer 43

FLUCTUATING

Question 44

Highly _______ environments have LONGER FOOD CHAINS than those in poorly stratified habitats e.g. Tropical Rainforest (TRF) vs. Talahib Grassland (TG)

Answer 44

STRATIFIED

Question 45

Wider food webs (those with more ______) are SHORTER than narrower food webs with a greater fraction of top predators

Answer 45

HERBIVORES

Question 46

2 VIEWS OF Community Structure Regulation

Answer 46

BOTTOM-UP REGULATION TOP-DOWN REGULATION

Question 47

Levels below limit levels above

Answer 47

BOTTOM-UP REGULATION

Question 48

Abundance at each level is controlled by consumers at the top of the food chain

Answer 48

TOP-DOWN REGULATION

Question 49

ecosystem collapse

Answer 49

Trophic Cascade