Competitive and Facilitation

Question 1

Competition

Answer 1

a reduction in fitness due to shared use of a resource that is in limited supply

Question 2

root competition

Answer 2

unlikely to result in competitive exclusion but advantage underground may result in being a better competitor above ground

Question 3

Liebig’s law of the minimum

Answer 3

growth is limited not by the total avaliable resources but by the avalibilty of the most limiting resource

Question 4

co-limitation

Answer 4

plants are limited by multiple resources

Question 5

direct interaction

Answer 5

direct effect of 1 species on another

Question 6

example of direct interactions

Answer 6

plants produce allelochemicals to inhibit other species growth

Question 7

most competitive interactions among plants are _______

Answer 7

indirect

Question 8

indirect interaction

Answer 8

indirect effect of 1 species on another

Question 9

example of indirect interactions

Answer 9

competition for nutrients

Question 10

competitive effect

Answer 10

ability to deny resources to a neighboring plant

Question 11

traits of a strong effect competitor

Answer 11

high leaf N, rapid growth rates, large leaves, often tall

Question 12

competitive response

Answer 12

ability to maintain function despite low resource levels or resources withdrawn by neighboring plants

Question 13

Plant neighborhood (zone of influence)

Answer 13

the plants that a given plant is competing with

Question 14

diffuse competition

Answer 14

includes a lot of different plants

Question 15

pairwise competition metrics

Answer 15

only used to compare 2 species

Question 16

plant neighborhoods generalities

Answer 16

neighborhood size is small
plants compete with closest neighbor
local neighborhood conditions (density, species competiton) determine the strength of competition a plant experiences
neighborhood sizes vary below and above ground

Question 17

Intraspecific competition

Answer 17

plants compete with neighbors regardless of species

Question 18

competitive exclusion principle

Answer 18

2 species cannot coexist when competing for the same limiting resource

Question 19

resource pool diversity

Answer 19

sum of the number of crop species in rotation and fertility sources

Question 20

When does facilation occur?

Answer 20

when net effects of neighboring plants are positive

Question 21

example of positive net effect

Answer 21

cushionplant buffering soil and air temps allowing other less tolerant plants to live

Question 22

mechanisms of facilitation

Answer 22

creation of better microclimate (nurse plant)
positive effect on soil N through N fixation
physical protection from herbivory
common mycorrhizal networks
mutual attraction of pollinators
soil modification

Question 23

competition __________ with productivity

Answer 23

increases

Question 24

shoot competition

Answer 24

increases with productive environments; favours fast species

Question 25

root competition

Answer 25

maximal at intermediate productivity; favours slow species

Question 26

strong competition often results in ___________

Answer 26

competitive exclusion

Question 27

what environment is facilitation most likely?

Answer 27

stressful environments