Week 6: Human Impacts on Ecosystems

Question 1

Ecosystem diversity decreases as

Answer 1

habitats are removed.

Question 2

Species diversity decreases as

Answer 2

Species diversity decreases as

Question 3

Genetic diversity decreases as

Answer 3

members of a species are displaced from an ecosystem or die as a result of human activity.

Question 4

Key threats to ecosystem and species diversity as a result of human activities include:

Answer 4

Habitat fragmentation
Climate change
Introduced species/pathogens
Agriculture

Question 5

Habitat fragmentation

Answer 5

when natural forests are broken up into smaller, isolated patches due to habitat destruction.

Question 6

Patches of habitat fragmentation

Answer 6

Cannot adequately sustain communities of organisms and rich biodiversity
Prevent gene flow as the patches are too far from each other to even fascillitate the movement of individuals

Question 7

Main contributing factor driving many species towards endangerment or extinction:

Answer 7

Habitat destruction

Question 8

It is vital to maintain natural vegetation to:

Answer 8

provide a range of habitats to help maintain species diversity.
help maintain and protect the soil from erosion
absorb carbon dioxide and produce oxygen.
help maintain regional rainfall patterns.
prevention of salinity

Question 9

Higher carbon dioxide concentrations cause

Answer 9

increasing temperatures, altering rainfall, rising sea levels, acidification of oceans impacting habitats, ecosystems and species

Question 10

What gases presence increases temperature in earth’s atmosphere?

Answer 10

greenhouses gases

Question 11

How do humans increase number of greenhouse gases?

Answer 11

through burning of fossil fuels + deforestation

Question 12

How do oceans become more acidified?

Answer 12

when excess CO2 dissolves into the water lowering the PH

Question 13

an introduced species?

Answer 13

any species that are brought to an area they aren’t usually found in either intentionally or by accident

Question 14

Why do introduced species population flourish in new ecosystems?

Answer 14

don’t have any natural predators

Question 15

Introduced species often outcompete native species that occupy the same/similar niches why?

Answer 15

due to a lack of viable competition and predation.

Question 16

Introduced pathogens do what?

Answer 16

bring diseases that organisms haven’t been exposed to before. They have not acquired immunity from it. Result in dramatic decline of population numbers.

Question 17

Indicator species

Answer 17

those whose presence, absence or abundance relates to a specific environmental condition.