Midterm

Question 1

Fundamental niche vs realized niche

Answer 1

fundamental - the multidimensional set of conditions an organism needs to survive

realized - the actual niche of a species whose distribution is restricted by biotic interactions (competition, predation, disease, parasitism)

Question 2

competition

Answer 2

the tendency of plants to utilize the same quantum of light ion, mineral nutrient and molecule of water

Question 3

competitive exclusion principle

Answer 3

two species with identical niches cannot coexist indefinitely, therefore coexisting species should occupy different niches

Question 4

the study by robert and John mcarthur included foliage height and bird species diversity, what was the outcome?

Answer 4

• forests with greater foliage height diversity support high bird species diversity
• plant communities with low foliage height diversity support low bird species diversity

Question 5

what is the paradox of the plankton

Answer 5

although resources needed are constant, heterogenicity in abiotic conditions and resource distributions allow coexistence

• plankton lives in open waters and compete or the same nutrients (N,P,Silica) but they coexist
• exclusion or coexistance is dependent on ratio of silicte and phosphate not absolute amount of nturients

Question 6

david tillman did a study on the niches of algae, what was the outcome?

Answer 6

two species could coexist where the population of each is limited by a different nutrient

• cyclotella dominates where silicate is most limiting to pop growth and asterionellla dominates where phosphorus is most limiting to pop gorwth
• when each pop is limited by a nifferent nutrient there is coexistance!

Question 7

tillmans landmark work clearly shows what?

Answer 7

that heterogeneity in resourse ratios, a form of environmental compelxity, influence community structure

Question 8

tillman state for a given species (2 things)

Answer 8

what are the resources and how variable the resources are

Question 9

what was robertsons study in the abandoned agricultural field?

Answer 9

studied NO3 concentrations and moisutre over 0.5 hectar area with 301 sample points
- they found there was a >10fold difference in measured variables, and little correlation between NO3 and moisture, there was sufficient spatial variability to affect plant community structure

Question 10

what was the study with bell and factors affecting sedge distributions in deciduous forests?

Answer 10

• utilized 11 clones of widespread carex species
• established 3-1000m transects in differnt areas and transplanted the clones at 10m intervals
• survived in areas of higher diveristy

Question 11

Ecology

Answer 11

the study of interactions among organisms and their environment

Question 12

Population ecology

Answer 12

Scientific study of structure and dynamics of populations

Question 13

Community ecology

Answer 13

the study of interactions occurring within a prescribed area between species (interspecific) and between species and their environment and the effects this has on community structure and function

Question 14

Interactions determine _______ level responses

Answer 14

community

Question 15

what is an ecological service?

Answer 15

communities do things if there are societal benefits these are call

Question 16

what is community structure?

Answer 16

• number of species S (richness)
• Relative abundance of species
• which species are present and aren’t present
• horizontal, vertical, and diagonal linkages

Question 17

species diversity takes into account both ________ and _______

Answer 17

numbers and abundance

Question 18

differentiate alpha beta and gamma diversity

Answer 18

alpha - diversity found within a small area (ex. patch of forest or grassland)

beta- diversity is a measure of how different patches are from each other

gamma - diversity is the total diversity found within the entire area, which includes all

Question 19

** what are some alternatives to species based approaches?

Answer 19

a taxon approach - focus on related species ex. gray wolves, eastern wolves, coyotes etc

A guild approach - ex. seed eating of Borel forest includes mammals, birds, insects, all interact to form a community, not all taxonomically related

Life form approach - ex. non species based approach based on location of overwintering buds, including ranker life for, based on location of the buds that give rise to new shoots

Functional approach - ● Based on how plants make a living (different photosynthetic pathways) C3, C4, CAM plants

Question 20

Guild

Answer 20

a group of organisms that make their living in a similar way

Question 21

Dominance

Answer 21

one or more species are substantially more abundant than other species

Question 22

_______ ______ is one of the most fundamental aspects of community structure

Answer 22

relative abundance

Question 23

what is log normal distribution?

Answer 23

bell shaped curve, most species have an intermediate abundance

Question 24

log normal distribution is affected by ?

Answer 24

sample size

Question 25

the more species sampled the more _____ species observed

Answer 25

rare

Question 26

you see a more intense distribution when you sample more comprehensively meaning ____ ______ ______ because of rarer species found

Answer 26

left hand sided

Question 27

how do you find the Shannon Weiner index?

Answer 27

you find the p value which is the # of individuals found for the species divided by the total individuals (do this for each species) then you multiply each p value by log(p) then you sum all the p values and apply the -

Question 28

the greater the diversity index means?

Answer 28

the more diverse the community

Question 29

pilous J measures species ____

Answer 29

eveness

Question 30

evens ranges from ___ - _____

Answer 30

0-1

Question 31

how do you find pilous J?

Answer 31

the Shannon weir index divided by logS which is species richness (ln5)

Question 32

what does evens describe?

Answer 32

the distribution of individuals

Question 33

with rank abundance curves, the more horizontal the slope the ______ the evenness

Answer 33

greater

Question 34

there is a strong correlation between habitat diversity and _______ level diversity

Answer 34

community level

Question 35

diversity increases with evens (T/F)

Answer 35

T

Question 36

for rank abundance curse the abundance rank is the ________ species and the proportional abundance is the _____ value

Answer 36

total #, p

Question 37

what is the difference between the node and the internode with plants?

Answer 37

node - point of attachment for each leaf | internode - space between the node

Question 38

what does it mean to propagate plants?

Answer 38

take a piece from the node and it will produce an axillary bud and adventitious roots

Question 39

diversity is important for richness, abundance, diversity and spatial distribution (T/F)

Answer 39

T

Question 40

what is the difference between fens and bog?

Answer 40

fens - groundwater fed, mineral rich, higher pH Bogs - rainwater fed, lower nutrients, minerals and pH is lower

Question 41

the northern hemisphere has ____ of all peatlands

Answer 41

1/3

Question 42

describe the 2 main ways to evaluate the impacts of biodiversity on the delivery of ecological services?

Answer 42

1. establish a species pool (gamma diversity) | 2. choose a subset and grow in experimental plots (alpha diversity) and compare productivity

Question 43

what was the reich study in cedar creek Minnesota?

Answer 43

they studied grassland communities in which they used measurements of 9x9 areas and 13x13m plots, and tested the relationship between biodiversity and ecological services

Question 44

What causes diversity function relationships?

Answer 44

a given ecological service will be highest in which a community has the highest microenvironment

Question 45

Balvanera studied what?

Answer 45

summarized 103 studies - rarified the relationship between diversity and procuvtivity - diversity affects primary consumer/producer abundance rise versa along with secondary and tertiary

Question 46

Complementarity

Answer 46

- a given ecological service will be highest/fastest in a community in which all resources/micro-environments are being exploited or occupied - a single species may not occupy the full niche space available - function will increase until all niche space is exploited

Question 47

Facilitation

Answer 47

some species enhance the growth of other | - reducing soil salinity, modifying water availability, nurse plants

Question 48

the study with the Caddisflies, was facilitation or complementarity?

Answer 48

facilitation as filter feeding was typically higher in mixed groups with different species than single species groups.

Question 49

zhu studied the genetic diversity with rice crops, what was the outcome?

Answer 49

- mixed genotype planting vs monocultures were more effective at reducing disease - eliminated the need for fungicide