Lecture 21-22

Question 1

primary production

Answer 1

the chemical energy generated by autotrophs during photosynthesis and chemosynthesis

Question 2

gross primary production

Answer 2

total amount of carbon fixed by autotrophs. controlled by climate as it its influenced by photosynthetic rates.

Question 3

net primary production

Answer 3

the amount of energy captured by autotrophs that result in an increase in biomass

Question 4

t/f NPP energy left over for plant growth and for consumption by detritivores and herbivores

Answer 4

true

Question 5

leaf area index

Answer 5

leaf area per unit ground area

Question 6

grassland and desert plants allocate more npp to roots because soil nutrients and water are scarce

Answer 6

true

Question 7

NPP can not be estimate from GPP and respiration measurements

Answer 7

false it can

Question 8

net ecosystem energy

Answer 8

the net change in co2 is gpp

Question 9

NPP increases as precipiation increases

Answer 9

true

Question 10

Npp increases with average annual temperature

Answer 10

true

Question 11

secondary production

Answer 11

energy derived from consuming organic compounds produced by other organisms

Question 12

1st trophic level

Answer 12

primary producers autotrophs produce the most organic matter in an ecosystem

Question 13

2nd trophic level

Answer 13

herbivores that consume the autotrophs

Question 14

3rd or higher trophic level

Answer 14

carnivores that consume animals from the level below

Question 15

primary producers

Answer 15

autotrops

Question 16

primary consumers

Answer 16

herbivores

Question 17

secondary consumers

Answer 17

carnivores

Question 18

tertiary consumers

Answer 18

carnivores

Question 19

interaction webs

Answer 19

describe tropic and non trophic interactions.

Question 20

t/f  terrestrial ecosystems,
only a small portion of the
biomass is consumed, and
most of the energy flow
passes through the detritus

Answer 20

true

Question 21

trophic pyramid

Answer 21

displays the amounts of energy or biomass in each trophic level

Question 22

t/f

Answer 22

in aquatic ecosystems the biomass pyramid is inverted

Question 23

bottom up view

Answer 23

resources that limit NPP determine energy flow through an ecosystem

Question 24

top down view

Answer 24

energy flow is controlled by rates of consumption at the highest trophic levels

Question 25

trophic cascades

Answer 25

trophic interactions that result in changes in biomass and species composition.

Question 26

what may control the number of trophic levels

Answer 26

amount of energy entering primary production frequency of disturbance ecosytem size

Question 27

community structure

Answer 27

the set of characteristics that shape communities

Question 28

species richness

Answer 28

the number of species in a community

Question 29

species evenness

Answer 29

relative abundance compared with one another

Question 30

taxonomic affinity

Answer 30

all bird species in a community

Question 31

guild

Answer 31

a group of species that use the same resources

Question 32

functional group

Answer 32

species that function in similar ways

Question 33

species accumulation curves help determine what?

Answer 33

when most or all of the species in a community have been observed

Question 34

species composition

Answer 34

identity of a species in a community

Question 35

trophic facilitation

Answer 35

a consumer is indirectly facilitated by a positive interaction between its prey and another species

Question 36

competitive networks

Answer 36

interactions among species where every species has a negative effect on every other species

Question 37

foundation species

Answer 37

dominant species

Question 38

ecosystem engineers

Answer 38

organisms that create, modify, or maintain physical habitat for themselves and other species

Question 39

interaction strength

Answer 39

measure of the effect of one species on the population size of another species

Question 40

keystone can be top predators but are not always

Answer 40

true

Question 41

redundant

Answer 41

having the same function as other species within a larger functional group

Question 42

disturbance

Answer 42

events that injure or kill individuals

Question 43

stress

Answer 43

abiotic factors that reduce growth, reproduction, or survival

Question 44

subtle change

Answer 44

gradual turnover of dominant species due to competition

Question 45

catastrophic change

Answer 45

large scale changes

Question 46

succession

Answer 46

change in species composition over time

Question 47

climax stage

Answer 47

the stable end point in succession that changes little.

Question 48

primary succession

Answer 48

slow progression initial conditions are inhospitable colonization of habitats that have no life

Question 49

secondary succesion

Answer 49

reestablishment of a community where some organisms have been destroyed occurs after fires/ storms

Question 50

facilitation model of succession

Answer 50

early species change the environment in ways that benefit later species.

Question 51

tolerance model

Answer 51

early species change the environment in ways that do not benefit nor harm later species

Question 52

inhibition model

Answer 52

early species change conditions in negative ways that hinder later species