Ecology Test 3/final

Front 1

open community

Back 1

edges blend into adjacent communities

Front 2

closed communities

Back 2

borders are sharp and defined

Front 3

keystones species are usually located at the ____________ of the food chain.

Back 3

top

Front 4

alpha diversity

Back 4

compared within one system

Front 5

beta diversity

Back 5

compared between 2 different sites in the same region

Front 6

gamma diversity

Back 6

compared between different regions

Front 7

community

Back 7

an assemblage of interacting populations of different species that forms an identifiable group. They can be open or closed, autotrophic or heterotrophic.

Front 8

species composition

Back 8

the most basic property of any community. includes the kinds and types of each species present, as well as the numbers and relative abundance of each species

Front 9

dominant species

Back 9

most common species in any community

Front 10

keystone species

Back 10

those that are not extrememly common, but which exert a large amount of control over the entire community

Front 11

dominance

Back 11

a measure of numbers in any community

Front 12

relative abundance

Back 12

a measure of the proportion of each species relative to the whole community

Front 13

species diversity (biodiversity)

Back 13

a combination of dominance and relative abundance. takes into account species richness and and species eveness

Front 14

species richness

Back 14

the number of species present

Front 15

species evenness

Back 15

the degree to which the individuals are allocated among the different species

Front 16

`diversity is a measure of _______________ on the community

Back 16

variation

Front 17

factors that promote diversity in a community

Back 17

1. complexity and size (unsaturated vs saturated)
2. proximity to the equator
3. strong resource diversity
4. level and kind of competition- narrow niches

Front 18

disturbance

Back 18

a change in environmental conditions that causes a change in the component species within a community. communities that receive a moderate amount of disturbance are actually benefited. Raise complexity, raise diversity.

Front 19

diversity is important because . . . .

Back 19

it promotes health, vigor, productivity, and stability within and community

Front 20

stability

Back 20

the ability of a community to handle disturbance, includes both resistance and resilience. High diversity will bring about stablilty because the loss of any one component can be compensated for by another component.

Front 21

resilience

Back 21

how well a community can bounce back

Front 22

resistance

Back 22

how well a community can resist change

Front 23

all communities possess a _______________ structure.

Back 23

physical (spatial)

Front 24

strata

Back 24

most communities are organized into vertical layers. This is known as stratification.

Front 25

in terrestrial communities, the strata themselves are caused by the ____________

Back 25

vegetation. note that grasslands have less strata than forests

Front 26

in aquatic communities, the strata are causesd by teh level of ____________

Back 26

of light penetration, as well as oxtgen and temperature gradients.

Front 27

zone of decomposition and regeneration

Back 27

the bottom strata

Front 28

zone of energy fixation

Back 28

upper stratum

Front 29

degree of vertical layering

Back 29

has a pronounced effect on the diversity of animal life in any community

Front 30

zonation

Back 30

the horizontal pattern of change in a community

Front 31

gaps

Back 31

openings in the canopy caused by teh death of a canopy tree

Front 32

horizontal patchiness

Back 32

adds to habitat complexity

Front 33

fragmented habitat

Back 33

severely clumped distribution of vegetation can lead to ...

Front 34

turnover rate

Back 34

the rate at which one species is lost and a replacement is gained

Front 35

equilibrium theory of island biogeography

Back 35

relates teh rate of colonization to the rate of extinction

Front 36

corridors

Back 36

can help fragmented habitats develpop better, although many species require a minimum critical size of habitat

Front 37

edge

Back 37

is a region where two or more communities meet. some species prefer edge, others prefer the interior of the habitat, and still others have no preference. edges can be induced or inherent, abrupt or gradual.

Front 38

ecotone

Back 38

a region where two or more communities not opnly meet, but integrate and blend together. they are usually areas of high diversity and complex relationships

Front 39

edge effect

Back 39

almost all edges are very rich regions with much diversity. in general, large, high cointrast edges that are adcancing into each other are of greatest value; however,too much edge effect can be detrimental to the ecosystem.

Front 40

scale-dependent community classification

Back 40

differences in community structure increase as we consider larger and larger areas

Front 41

temporal structure

Back 41

refers to daily and seasonal sycles of activity within the community. the most striking example of this is seasonal change.

Front 42

hopkin's bioclimactic law

Back 42

relates the occurence of spring events to latitude, elevation, and longitude.

Front 43

trophic (feeding) levels

Back 43

food chains, food webs. (this is known as trophic structure)

Front 44

chemical ecology

Back 44

the study of the production of chemical compounds by organisms and the uptake or reception of these chemical compounds by other organisms.

Front 45

open community

Back 45

edges blend into adjacent communities

Front 46

closed community

Back 46

borders of edges are sharp and defined

Front 47

saturated community

Back 47

most/all niches are full. This is good for diversity.

Front 48

unsaturated community

Back 48

many unfilled niches

Front 49

extreme regions have ___________ diversity

Back 49

low

Front 50

layers of an aquatic ecoysystem

Back 50

epilimnion, hypolimnion, metalimnion

Front 51

emergent trees

Back 51

grow above the canopy

Front 52

light based layers of an aquatic ecosystem

Back 52

littoral, limnetic, profundal zones

Front 53

thermocline

Back 53

rapid decline in temp

Front 54

four factors that contribute to diversity

Back 54

complexity and size (saturated vs unsaturated), proximaty to the equator, strong resource diversity, level and kind of competition (narrow niches)

Front 55

communities

Back 55

groups of interacting population of different plant and animal species

Front 56

integrated (organismal) concept

Back 56

community composition is predictable. community is a while, stable, and orderly. coactions are classified.

Front 57

individualistic concept

Back 57

community composition is not predictable. coexistance is the result of similar requirements and tolerances

Front 58

non-directional changes

Back 58

do not alter community permanently. short term and cyclic. ex: daily, seasonal changes.

Front 59

directional changes

Back 59

alter the community permanently. long-term, non-cyclic. ex: extinction, succession.

Front 60

replacement changes

Back 60

are those involving the replacemtnt of one individual by another of the same or different species

Front 61

cyclic replacement

Back 61

involves any kind of replacement activity that occurs in a continuous cycle, such as canopy replacement.

Front 62

fluctuations

Back 62

alterations in community structure or composition that occur as a result of shifts in habitat factors. habitats in whihc fluctuations occurs often experience "species shifts" CLIMATE IS A MAJOR FACTOR

Front 63

ecological succession

Back 63

the orde3rly change in community structure, composition, and dynamics over time. includes both change and devvelopment. can be though of as teh orderly and preofressive replaement of one community by another unil a relatively stable community (climax community) occupies the area.

Front 64

three factors used to predict thej outcome of succession in a community

Back 64

particular traits of species involved, how the species interact, and the environmental conditions

Front 65

successional series or sere

Back 65

whole sequence of communities that terminates in a climax community

Front 66

seral stage

Back 66

intermediate community existing at different points in time

Front 67

microseres

Back 67

minor successional sequences that occur within the framework of a larger community

Front 68

paleoecology

Back 68

the study of past relationships of ancient flora and fauna in the environment

Front 69

succession is initiated by _____________

Back 69

disturbance. with the net result being that the community is forced to change. Such changes can be due to the behavior of species already present in the community (autogenic) or due to outside forces (allogenic.)

Front 70

aquatic succession

Back 70

th edevelopment of a pond or other aquatic system into a mesic forest.

Front 71

eutrophication

Back 71

the mineralization of a pond until it builds up and becomes a marsh and eventually a forest.

Front 72

terrestrial succession

Back 72

the development of a field or new region in to a forest system

Front 73

primary succession

Back 73

is the establishment of a community where none previously existed, or where an area had its soil seriously depleted

Front 74

secondary succession

Back 74

is the reestablishment of a community where a preexisting community was disturbed in some way

Front 75

autotrophic succession

Back 75

available energy INCREASES throughout the process

Front 76

heterotrophic succession

Back 76

availbale energy DECREASES thoughout the process

Front 77

eutrophic systems

Back 77

are those rich in nutrients

Front 78

oligiotrophic systems

Back 78

are those with limited nutrients and productivity

Front 79

pioneer species

Back 79

are the first to inhabit a new area. once established, they form a pioneer community

Front 80

pioneer community

Back 80

which begins to break down rock to build up soil. fast growing grasses, shrubs, water tolerant trees, trees with intermediate water tolerance, and, finally water intolerant trees then inhabit the area.

Front 81

animal species move into an area in parallel with )_________________

Back 81

vegetation

Front 82

heterotrophic succession

Back 82

occurs in communitites involved in decompositions. it is characterized by early dominance of fungi and explainingg how much each stage is dependent upon the previous one