Human Impact

Question 1

Planetary Boundaries definition:-

Answer 1

9 global processes which regulate the stability of the land air and sea.

Question 2

Planetary boundary tipping point

Answer 2

point that may be reached when a small change in a boundary can have a large and unpredictable effect on the environment.

Question 3

4 boundaries that have been crossed:-

Answer 3

• biodiversity.
• Climate change
• Land system change
• N and P flows to the biosphere and oceans.

Question 4

Boundary that has been avoided:-

Answer 4

Stratospheric ozone depletion.

Question 5

2 boundaries that can be avoided:-

Answer 5

• Ocean acidification

- freshwater consumption and the global hydrological cycle

Question 6

2 Boundaries which insufficient data

Answer 6

• Chemical pollution and the release of novel entities

- atmospheric aerosol loading

Question 7

4 main reasons for species endangerment

Answer 7

• overharvesting
• habitat destruction
• alien species
• pollution

Question 8

Alien species effects (3)

Answer 8

• lack of awareness of humans as predators (hunting)
• introduction of previously non-present predators
• mass consumption of herbivore food-competition.

Question 9

Driver for human impact effects-

Answer 9

Inc world pop = inc food demand.

Also, increased affluence (= increased demand for ‘luxury’ food) e.g salmon, avocadoes.

Question 10

6th mass extinction-

Answer 10

Extinction exceeding the normal background level due to natural selection evidenced by fossils.

Question 11

Biggest contributor to species endangerment-

Answer 11

Habitat destruction.

Question 12

4 methods of trying to prevent overfishing-

Answer 12

• quotas (however, when exceeded, caught fish are dumped).
• min net sizes to enable immature fish to survive and reprod.
• closed seasons.
• protected areas (marine resource)/exclusion zones.

Question 13

Sustainable development definition

Answer 13

development which can continue indefinitely because it is based on exploiting renewable resources whilst minimalising environmental damage.

Question 14

Biological conservation-

Answer 14

aims to maintain the quality of natural enviros and their biological resources, utilising active management of biotic and abiotic elements to ensure max species survival and genetic diversity.

Question 15

Biotic resources actively managed- (2)

Answer 15

• food

- mates

Question 16

Abiotic actively managed-(2)

Answer 16

• living space

- shelter

Question 17

ID-ing of indivs and species by ecologists to conserve gen diversity-

Answer 17

DNA profiling and genetic markers (genetic variation unique to an indiv/species that can be ID-ed as a particular nucleotide sequence with a known location on a chromosome.

Question 18

In situ conservation-

Answer 18

In natural enviro. Occurs with diverse gene pool. Depends on habitat conservation- coppicing, grazing, mowing, establishing wildlife corridors to reduce isolation, etc.

Question 19

Hunting regulators-

Answer 19

CITES

Question 20

Ex situ conservation-

Answer 20

Outside natural environment. Restricted gene pool. E.g breeding, sperm/seed banks, botanical gardens/zoos.

Question 21

Conservation method- EIA

Answer 21

Environmental impact assessment- carried out to consider effects of urb dev on nat habitats.

Question 22

Conservation method- legislation

Answer 22

protects endangered species

Question 23

Conservation method- reintroduction

Answer 23

breeding then re-releasing into an enviro

Question 24

Conservation method- SACs, etc

Answer 24

Special areas of conservation. Sites of special scientific interest. National parks,etc.

Question 25

Conservation method- wind breakers

Answer 25

reduces wind soil erosion

Question 26

Conservation method- maintaining indigenous hardwood forests

Answer 26

provide greater habitat and spec diversity compared to introduced softwood forests.

Question 27

Conservation method- planting soft woods

Answer 27

intermixed w/ hardwoods, increase biodiversity.