Ecosystems at Risk: Vulnerability and Resilience of Ecosystems

Question 1

what are the causes of ecosystem vulnerability

Answer 1

location
extent
linkages
biodiversity

Question 2

the four following locational factors affect the functioning of ecosystems…

Answer 2

latitude
distance from sea
altitude
microclimatic features

Question 3

true or false: The greater the degree of specialisation an organism has to a particular set of environmental conditions the more vulnerable that organism is to the changes in those conditions.

Answer 3

true

Question 4

what does extent mean in relation to vulnerability

Answer 4

Ecosystems that are restricted to relatively small areas or have already been subject to extensive disturbance are especially vulnerable.

Question 5

what does linkages mean in relation to vulnerability

Answer 5

Ecosystems that have high levels of interdependence are much more vulnerable to change.

eg. if an organism relies on one producer for survival, and that producer is wiped out, the consumer is at greater risk of being wiped out also

Question 6

what is genetic biodiversity in relation to vulnerability

Answer 6

genetic diversity favours the survival of a species as it increases the chance that some members of the population will have the characteristics to be able to withstand changes in environmental conditions.

Question 7

what is species biodiversity in relation to vulnerability

Answer 7

the greater the species diversity within an ecosystem the more able the ecosystem will be able to withstand threats.

Question 8

what is ecosystem biodiversity in relation to vulnerability

Answer 8

the greater the number of habitats, biotic communities and ecological processes occurring, the easier it will be for the ecosystem to revoke from threats or changes in environmental conditions.

Question 9

what are natural stresses in relation to vulnerability

Answer 9

stresses that the ecosystem that can withstand, as they are accommodated to the ecosystem. the ecosystem has pioneer species able to respond to the stress and rebuild

Question 10

example of natural stresses

Answer 10

coral reefs are frequently damaged by tropical cyclones, but it has many pioneer species. Mangroves are also strong pioneer species.

Question 11

what are human induced stresses

Answer 11

stress placed on ecosystems by humans

Question 12

example of human induced stress

Answer 12

land-clearing and cropping, this creates a simplifies ecosystem and one encourages pests.

Question 13

how can location make a system vulnerable

Answer 13

a species such as coral is adapted to shallow, nutrient-deficient waters. if there was an increase in nutrients in the water, algae growth is promoted, leading to a reduction of sunlight for coral growth.

or if the temperature increased in coral reef waters, it causes the coral polyp to die

Question 14

define extent

Answer 14

size of an ecosystem

Question 15

are ecosystems that overlap and rely on each other less vulnerable than smaller ecosystems with definitive boundaries

Answer 15

yes

Question 16

define keystone species

Answer 16

an organism that helps define an entire ecosystem

Question 17

what are the three levels of biodiversity

Answer 17

ecosystem, genetic and species

Question 18

what effect does having more intertwined levels of biodiversity have on the vulnerability of an ecosystem

Answer 18

the more intertwined, the less vulnerabl

Question 19

why does biodiversity decrease the vulnerability of an ecosystem

Answer 19

1. a range of pathways for ecological processes
   
   • if one pathway is destroyed, an alternative is found and the ecosystem continues to function as normal

Question 20

why does biodiversity decrease the vulnerability of an ecosystem

Answer 20

1. a range of pathways for ecological processes
   
   • if one pathway is destroyed, an alternative is found and the ecosystem continues to function as normal

Question 21

the greater the level of diversity =

Answer 21

greater oppurtunity to adapt to change

Question 22

why does genetic diversity decrease the vulnerability of an ecosystem

Answer 22

organisms within the ecosystem having different characteristics means there is a larger chance of some of the organisms surviving a change

Question 23

what is ecosystem diversity

Answer 23

the diversity within an ecosystem in terms of habitat differences, biotic communities and the variety of ecological processes

Question 24

what is linkages also known as

Answer 24

interdependence

Question 25

the greater the level of linkages/interdependence...

Answer 25

the greater the ecosystems ability to absorb change eg. loss of a primary consumer from a food web is unlikely to have a major impact on secondary consumers due to range of alternative primary consumers.

Question 26

the lower the level of linkages/interdependence...

Answer 26

much more vulnerable to change eg. Krill are the dominant primary consumer organism and the main source of food/energy for some species of whales, with no intermediary stages in the food change. If there is a reduction of krill, it will directly impact the number of whales the ecosystem can support.

Question 27

Under what conditions does long-term degradation occur?

Answer 27

Long-term ecosystem degradation occurs when the magnitude and duration of the stress exceed the ability of the component to repair itself.

Question 28

list natural sources of catastrophic environmental stress

Answer 28

 DROUGHT  FLOOD  FIRE  VOLCANIC ERUPTION  EARTHQUAKE  LANDSLIDE  CHANGE IN STREAM COURSE  DISEASE

Question 29

list natural sources of gradual environmental stress

Answer 29

 Natural climactic changes  Immigration/invasion of new species  Adaption/evolution  disease

Question 30

what are the two types of stress

Answer 30

natural human induced

Question 31

what are the two rates of stress

Answer 31

gradual catastrophic

Question 32

what are the two magnitudes of stress

Answer 32

slight extreme

Question 33

what are some human induced causes of environmental degradation

Answer 33

population growth poverty debt non-sustainable consumption damaging waste non-sustainable agricultural practices exploitation of natural resources

Question 34

how do humans modify energy flows and nutrient cycles

Answer 34

either removing or adding organisms or nutrients to an exosystem

Question 35

what is an example of humans removing organisms and nutrients

Answer 35

hunting and traditional agricultural methods (without fertilisers)

Question 36

what is an example of humans adding organisms and nutrients

Answer 36

introducing species and modern agricultural methods

Question 37

how can humans modify relationships between biophysical components

Answer 37

they can modify how the spheres and natural processes interact. eg. removing vegetation from an area can loosen soil, causing it to be washed away eg2. restricting the amount of water that flows down a river, impacting organisms that live downstream

Question 38

how do humans modify mount kosciuszko

Answer 38

land clearing for ski runs removes nutrients, and loosens top soil that will erode. the land clearing results in a loss of biodiversity humans redirecting streams in mount kosciuszko alters the biophysical components