Exam 4

Question 1

therophytes

Answer 1

annuals survive unfavorable periods as seeds. Complete life cycle from seed to seed in one season

Question 2

geophytes (cryptophytes)

Answer 2

buds buried in the ground on a bulb or rhizome

Question 3

hemicryptophytes

Answer 3

perennial shoots or buds on the surface of the ground, often covered with litter

Question 4

chamaephytes

Answer 4

perennial shoots or buds on the surface of the ground to about 25 cm above the surface

Question 5

phanerophytes

Answer 5

perennial buds carried well up in the air, over 25 cm. Trees, shrubs, and vines

Question 6

epiphytes

Answer 6

plants growing on other plants; roots up in the air

Question 7

community

Answer 7

the collection if animal and plant populations interacting directly or indirectly

Question 8

guilds

Answer 8

feeding groups

Question 9

bird species become more diverse as vertical stratification

Answer 9

increases in forest ecosystems

Question 10

vertical stratification

Answer 10

vertical layering of a habitat; the arrangement of vegetation in layers, a key factor for structuring their species richness and biodiversity

Question 11

phenology

Answer 11

the study of cyclic and seasonal natural phenomena, especially in relation to climate and plant and animal life

Question 12

keystone

Answer 12

a predator controls the structure of the community and so must be regarded as the dominant species

Question 13

dominance=

Answer 13

basal area or aerial coverage, species A/ area sampled

Question 14

relative dominance=

Answer 14

basal area or coverage, species A/ total basal area or coverage, all species

Question 15

Shannon- Weiner index

Answer 15

H = n log n - sum fi log fi /n
this formula is used to measure the evenness of diversity
fi= the number of individuals in a given species

Question 16

competition if more evident among

Answer 16

the species of the same guild (eating the same food) ex: chipmunks

Question 17

food chain

Answer 17

feeding relationships in nature are not simple straight-line chains but complex webs
grass > grasshopper > flycatcher > hawk

Question 18

what limit herbivores

Answer 18

autotrophs

Question 19

what does the bottom-up regulation view emphasize

Answer 19

the limitations imposed by the availability of food resources

Question 20

succession

Answer 20

in its most general definition is the temporal change in community structure through time, begins with disturbance

Question 21

Henry Chandler Cowles

Answer 21

studied ecological succession in the Indiana Dines of Northwest Indiana. This led to efforts to preserve the Indiana Dunes

Question 22

FE Clements

Answer 22

described plant succession (the word)

Question 23

characteristics of disturbance

Answer 23

4 factors
1. the magnitude of the physical force, such as the strength of the wind, or the heat of a fire
2. the morphological characteristics of the organisms that influence their response to the disturbance
3. the nature of the substrate (soil). Is the soil wet, dry, clay, or sand
4. The amount of aboveground biomass accumulation and height of vegetation

Question 24

frequency

Answer 24

the mean number of disturbances that occur within a particular time interval

Question 25

return interval

Answer 25

the interval between disturbance events

Question 26

if intervals between disturbances are long, or frequency is low

Answer 26

biomass accumulates and the intensity of disturbance can be high

Question 27

four premises of community dynamics

Answer 27

1. the fundamental niche of a species acts as a primary constraint on its distribution and abundance 2. species vary in their fundamental niches (environmental tolerances) 3. Environmental conditions change in time and space 4. the fundamental niche is modified by species interactions (realized niche)

Question 28

Logging story

Answer 28

succession began with the development of a bare site, called nutation (disturbance) nutation was followed by migration, the arrival of propagules onto the area migration was followed by the establishment and initial growth of vegetation the outcome of the process was the replacement of one plant community by another reaching a phase called stabilization

Question 29

maple and beech seeds are distributed by

Answer 29

wind

Question 30

pine seeds are distributed by

Answer 30

animals

Question 31

dominance of short overstay and understory of pine to hardwood

Answer 31

in the early stages of plant succession, shade-tolerant species come to dominate as a result of their high growth rates shade-intolerant species overtop and shade the slower-growing, shade, tolerant species as time progresses and light levels decline below the canopy, seedlings of the shade-intolerant species cannot grow and survive in the shaded conditions at this time, although the shade-intolerant species dominate the canopy, no new individuals are being recruited into the populations

Question 32

climax

Answer 32

end point of succession

Question 33

classical ecological theory

Answer 33

succession stops when the sere has arrived at an equilibrium or steady state with the physical and biotic environment, at this point the community is stable and self-replicating

Question 34

characteristics of climax

Answer 34

the vegetation is tolerant of the environmental condition it has imposed upon itself it has a wide diversity of species complex food chains well-developed spatial structure individuals in the climax stage are supposedly replaced by others of the same kind. thus the species composition maintains an equilibrium

Question 35

Jack Pine Forests

Answer 35

jack pine is a fire adapted species found in the Great Lakes region of North America

Question 36

serotiny

Answer 36

jack pine have seeds that remain in the cone for years awaiting a fire the fire melts the resins that kept the cone sealed up then the pine seeds are ready for rely prepared ground of ash

Question 37

Kirtland's Warbler

Answer 37

endangered; limited geographical range nest in jack pine trees, cowbird trapping to save the warblers, if human involvement stops, could become endangered again

Question 38

frequency rolling plains

Answer 38

how frequently a fire burns over a given area, and its return rate is influenced by the occurrence of droughts, accumulation and flammability of fuel, the resulting intensity of the burn, and human interference

Question 38

what seed reserves become depleted with too many fires

Answer 38

shrubs in chaparral of cali

Question 39

Wind as a force of succession

Answer 39

wind shapes the canopies of trees exposed to prevailing winds, affects their growth, and uproots them from the ground. trees weakened by fungal disease, insect damage, lightning strikes and tropical forests trees carrying a heavy load of epithets in their crowns are candidates for wind throw

Question 40

hurricane

Answer 40

a powerful recurring event of high intensity but low frequency those with speeds in excess of 166km/hr and associated rainfall of 200mm, have devastating impact on ecosystems

Question 41

affect of strong winds with heavy snowfall

Answer 41

weighs down trees and heavy rains soften the soil about the roots

Question 42

cyclic replacement in an oil-field community in Michigan

Answer 42

the bare areas at the bottom are invaded by moss mosses are invaded by Canada bluegrass and dock the accumulated dead leaves of these plants are covered by lichens that crowd out the grass rain, frost, and wind destroy the lichens to start the cycle with bare ground again

Question 43

chronoseres

Answer 43

come back

Question 44

chronosequences

Answer 44

come back

Question 45

allogenic environmental change

Answer 45

purely abiotic environmental (allogenic) change can produce patterns of succession over time scales ranging from days to millennia or longer annual fluctuations in temp and precipitation will influence the relative growth responses of different species in a forest community, but they will have little influence on the general patterns of secondary succession in contrast, shifts in environmental conditions that occur at periods as long or longer than the organism's life span are likely to results in shifts in species dominance

Question 46

primary succession

Answer 46

begins on sites that never have supported life

Question 47

examples of primary succession

Answer 47

rock outcrops and cliffs, sand dunes, and newly exposed glacial till

Question 48

soil succession

Answer 48

light is not the only environmental factor that changes over the course of succession atmospheric nitrogen must fix and be incorporated into the plants, where it can later be broken down and made available in the soil through the process of decomposition nitrogen fixing rhizobium, such as with alder, can grow and dominate a "new" site this pattern of increasing accumulation of litter and other nutrients was shown in primary succession at glacier bay, alaska

Question 49

plant diversity increases with

Answer 49

site age

Question 50

old-field succession in the Piedmont of north Carolina

Answer 50

a famed crop land is abandoned, the ground in claimed by crabgrass, whose seeds lying dormant in the soil, respond to light and moisture and germinate in late summer seeds horse weed ripen the following spring horse weed, claims the field over crabgrass

Question 51

secondary succession

Answer 51

by the third summer broomsedge a perennial bunchgrass, invades the field about this pine seedlings, find room to grow in open places among the clumps of broomsedge invade the field within five years the pines are tall enough to shade out the broomsedge eventually hardwood species, such as oaks and ash, grow up through the pines and the pines die development of the hardwood forest continues as shade tolerant trees and shrubs fill the understory

Question 52

temporal changes in dominant phytoplankton

Answer 52

seasonal changes in temperature, photoperiod, and light intensity produce a well-known succession of dominant phytoplankton in freshwater lakes, which is repeated with little variation each year

Question 53

autogenic change (self-generated)

Answer 53

one feature common to all plant succession is autogenic environmental change. In both primary and secondary succession, the colonization of an area by plants alters the environmental conditions one clear example is the alteration of the light environment

Question 54

influence of herbivores on community dynamics

Answer 54

herbivores modify community dynamics, directly and indirectly by selecting certain plant species, herbivores directly influence mortality and recruitment, favoring the population the population growth of one species over another

Question 55

Moose on Isle Royale in Lake Superior

Answer 55

selectively feed on the seedlings and saplings of deciduous hardwood tree species of aspen, birch, ash, and maple, ignoring the conifer species long-term experiments using exclosures to exclude moose from certain areas have changed the community structure of the island. In the exclosures, the abundance of the deciduous hardwood species is much higher

Question 56

degradative succession

Answer 56

succession that occurs on dead organic matter over a relatively short time-scale. Detritivores feed in sequence, each group releasing nutrients that are utilized by the next group in the sequence until the resources are exhausted.

Question 57

shifting mosaic

Answer 57

the process of succession is never ending, brought about by the continuous processes of birth, growth, and death of individuals within the community this view of succession suggests a shifting mosaic steady state the community being composed of a mosaic of patches, each in a phase of successional development