lecture 24

Question 1

What is a habitat patch

Answer 1

a homogenous area containing suitable conditions and resources needed to sustain a population

Question 2

_____ occur within habitat patches

Answer 2

communities or populations of many species

Question 3

what divides habitat patches

Answer 3

they are heterogeneously distributed over the landscape separated by unsuitable habitat

Question 4

Habitat patches result in:

Answer 4

many local, isolated communities that may interact through dispersal (emigration and immigration)

Question 5

the degree of interaction between habitat patches (or dispersal) depends on the ability to disperse between habitat patches which depends on three things:

Answer 5

• distance between patches
• suitability of habitat between patches
• barriers (eg mountain, ocean)

Question 6

what is a landscape

Answer 6

a collection of communities that exist as patchwork assembly called a mosaic

Question 7

landscape ecology

Answer 7

the study of the causes and consequences of landscape spatial variation

Question 8

landscape ecology focuses on features such as:

Answer 8

distribution, shape and spatial arrangement of patches

Question 9

naturally occurring patches reflect:

Answer 9

regional variations in geology, topography, soil and climate

Question 10

describing a landscape involves two main things

Answer 10

1) landscape composition and

2) landscape structures

Question 11

landscape structures involves 5 things:

Answer 11

1) large versus small patches
2) how dispersed patches are
3) shape of patches(simple versus complex)
4) how fragmented the landscape is
5) landscape scale

Question 12

grain

Answer 12

smallest homogenous unit that is the focus of the study

Question 13

extent

Answer 13

total area/time period covered

Question 14

What is the island biogeography theory

Answer 14

ASSUMING: larger islands (habitat patches) hold more species than smaller islands, the number of species on an island (patch) is determined by the dynamic equillibrium between

1) colonization of species to the island
2) extirpation of species from the island

Question 15

as the number of species increases, the rate of species successfully colonizing

Answer 15

decreases because early arrivals use up available habitats and resources

Question 16

fundamental niche

Answer 16

available habitats and resources

Question 17

as the number of species increases, the rate of species being extirpated

Answer 17

increases because of increased competition (competitively dominant species outcompete others)

Question 18

S

Answer 18

(equilibrium species richness) is when colonization=extirpation (S is stable but species composition may change)

Question 19

distance between patches and island size patches influences 3 things:

Answer 19

• colonization
• extirpation
• S

Question 20

2 predictions of IBT

Answer 20

1) as distance between patches increases, colonization rates decrease (less successful journey btwn patches) leading to lower S per patch
2) larger patches have lower extirpation leading to higher S (more resources and habitats and meets needs for larger variety of species)

Question 21

main cause of anthropogenic extinction is

Answer 21

habitat loss/destruction

Question 22

habitat destruction results in:

Answer 22

highly fragmented landscapes -leaving much smaller habitat patches that are further appart relative to natural conditions (lower S)

Question 23

in fragmented landscapes; apply IBT to determine:

Answer 23

size and distance btwn patches appropriate to maximise and maintain biodiversity (species richness)

Question 24

examples of human activities fragmenting existing patches into smaller and more isolated patches

Answer 24

converting grasslands/forest–>agriculture

roads and infrustructure

settlements

Question 25

habitat fragmentation causes

Answer 25

disruption of communities

Question 26

each habitat patch is composed of:

Answer 26

interior and edge/borded

Question 27

patch interior

Answer 27

habitat has its own environmental conditions and community structure

Question 28

edge/borded

Answer 28

transition zone where community structure and environmental conditions of adjacent patches are blended

Question 29

edge effect

Answer 29

diverse environmental conditions allow edges to support high species diversity

Question 30

interior species=

Answer 30

require stable environment of interior habitats

Question 31

is there an abrupt change between interior and exterior of patches

Answer 31

NO

Question 32

edge species

Answer 32

can survive under unstable conditions of the edge habitat

Question 33

what two things affect edge:interior habitat ratio

Answer 33

1) PATCH SIZE INCREASES than edge:interior ratio decreases | 2) PATCH WIDTH INCREASE than edge:interior ratio decreases

Question 34

as the ratio of edge | :interior habitat changes, so will the diversity of the community

Answer 34

more diversity with more edge habitat if interior habitat remains

Question 35

transition zone

Answer 35

patch borders between one patch to the next

Question 36

transition zones represent areas of

Answer 36

contact, seperation, and transition

Question 37

transition zones connect patches allowing the transfer of:

Answer 37

energy, material and organisms

Question 38

transition zones vary in

Answer 38

shape, size, length of transition

Question 39

corridor

Answer 39

strips of habitat that contain favourable conditions that connects different patches together

Question 40

corridors help to

Answer 40

connect travel lanes, aid in colonizing new patches, important in landscape dominated by humans, reconnect populations

Question 41

ecosystem management in general is for:

Answer 41

preserving endangered interior species

Question 42

5 general ideas of ecosystem management:

Answer 42

1) larger is better than smaller 2) closer together is farther apart 3) better connected by habitat corridors 4) compact shapes are better for minimizing boundary length 5) a buffer zone is preferable