Planetary boundaries(Human impacts on the environment)

Question 1

what are the 9 processes that regulate the stability of the land, atmosphere, and sea

Answer 1

Atmospheric aerosols
Biodiversity integrity
Fresh water use
climate change
ozone depletion
Biogeochemical flows( nitrate and phosphate)
Novel Entities(inorganic pollution boundary)
Land- System Change
Ocean Acidification

Question 2

what is the aim of the planetary boundary concept

Answer 2

to define environmental limits within which humanity can safely operate

Question 3

causes of the climate change boundary

Answer 3

increase in greenhouse gas levels, particularly carbon dioxide levels

Question 4

what does an increase in carbon dioxide levels cause

Answer 4

Global warming

Question 5

2 activities that lead to an increase in greenhouse gas levels

Answer 5

deforestation
burning of fossil fuels

Question 6

what is the boundary for climate change

Answer 6

atmospheric concentrations of carbon dioxide should not exceed 300ppm

Question 7

what are the consequences if the climate change boundary is exceeded

Answer 7

*could lead to thermal expansion and melting of ice caps which raise the sea level, leading to flooding of low-lying lands, habitat destruction, and reduction in biodiversity.

• Increased temperature affects wind
  patterns, ocean currents, and rainfall.
  These affect the survival of plants and
  animal species in certain areas.

Question 8

measures to prevent us from exceeding the climate change boundary

Answer 8

• Reduce/stop burning fossil
  fuels
• Reduce deforestation
• Alternative fuel sources
  including biofuels

Question 9

Biofuels

Answer 9

Biofuel is a fuel that is produced over a short time span from biomass, rather than by the very slow natural processes involved in the formation of fossil fuels, such as oil.

Question 10

Boundary for biodiversity

Answer 10

Maintain 90% of biodiversity

Question 11

causes of biodiversity loss

Answer 11

• Habitat destruction
  e.g. tundra, coral
  reefs, tropical rain
  forests, marine
• Hunting

Question 12

consequences of loss in biodiversity

Answer 12

Reduction in species number/ extinction, as the species, cannot evolve quickly enough to adapt to the environmental changes caused by humans

Question 13

4 ways to protect species

Answer 13

• Monitor biodiversity
• Species conservation via
  gene banks e.g. seed banks,
  sperm banks
• Prohibit international trade in endangered species and their products
• Fishing quotas
  *increase public awareness

Question 14

what is the land use change boundary

Answer 14

maintain 75% of the planet’s original forests

Question 15

the problem with land use change

Answer 15

• Land use change
  (including
  deforestation) for
  food and biofuel
  production, urban
  development,
  livestock farming,

Question 16

consequences of exceeding the land use change boundary

Answer 16

• The production of biofuel crops and
  crops grown for export means that
  not enough food may be produced for
  local use.
• Reduction in biodiversity

Question 17

how to live within the land use change boundary (remedial measures)

Answer 17

• Farming should be
  concentrated in the most
  productive areas only.
• Reduce meat consumption.

Question 18

causes of the biogeochemical flow boundary(nitrate and phosphate boundary)

Answer 18

• Use of fertilizers
  containing nitrates
  and phosphates.
• Agricultural nitrogen fixing
• combustion of fossil fuels and biomass

Question 19

what is the boundary for biogeochemical flow

Answer 19

Worldwide use per year of about
11 teragrams (Tg) of phosphate and 62 Tg of
nitrate

Question 20

consequences of exceeding the biogeochemical flow boundary

Answer 20

Eutrophication from nitrate and
phosphate run-off into bodies of
water

Question 21

remedial measures for the biogeochemical boundary

Answer 21

Reduce the use of fertilizers

Question 22

the ozone boundary

Answer 22

Less than 5% below pre-industrial level of about 290 Dobson Units

Question 23

causes of the ozone boundary

Answer 23

CFC use in aerosols,
refrigerator coolants
etc

Question 24

consequences of exceeding the ozone boundary

Answer 24

• Ozone layer destruction
• Increase in UV light increasing DNA
  mutations, skin cancers, and cataracts

Question 25

remedial measures to solve the problem with the ozone boundary

Answer 25

CFCs were banned and the the ozone layer is re-building.

Question 26

ocean acidification boundary

Answer 26

When the oceans become acidified enough that the minerals that sea creatures need to make shells begin to dissolve

Question 27

causes of the ocean acidification boundary

Answer 27

* Burning fossil fuels and increased carbon dioxide levels. * Carbon dioxide dissolves in seawater and forms H2CO3 which releases H+ ions / lowers pH/ increases acidity

Question 28

consequences of exceeding the ocean acidification boundary

Answer 28

* Low pH causes calcium carbonate to leach out of corals, the shells of mollusks and the exoskeletons of Arthropods. Even if the organisms survive this, they become softer and more vulnerable to predators. * Could reduce biodiversity

Question 29

remedial measures to deal with problems of ocean acidification problem

Answer 29

Reduce carbon dioxide levels by reducing fossil fuel combustion and deforestation.

Question 30

the freshwater boundary

Answer 30

We can use up to 4000km2 of freshwater per year

Question 31

causes of the freshwater boundary

Answer 31

* Increased water use in Agriculture (irrigation) and industry. * Climate change * Pollution of water * Change in land use e.g. draining wetlands, deforestation

Question 32

consequences of exceeding the freshwater boundary

Answer 32

Reduction in freshwater available

Question 33

remedial measures to deal with the problem of the freshwater boundary

Answer 33

* Stop irrigating non-food crops e.g. biofuels * Reclaim waste water for irrigation/industry * Use desalinated water

Question 34

the aerosol boundary

Answer 34

unknown

Question 35

causes of the aerosol boundary

Answer 35

The atmosphere contains minute particles such as ash and soot from burning and coal power stations, dust from quarrying.

Question 36

consequences of using too much aerosol

Answer 36

* Increase in respiratory problems and lung cancers. Estimated to cause 800,000 premature deaths per year * It can build up on leaves and reduce photosynthesis

Question 37

remedial measures to deal with the problem of the aerosol boundary

Answer 37

we are unable to determine safe limits currently(unknown)

Question 38

causes of the inorganic pollution boundary (novel entities)

Answer 38

* synthetic organic pollutants e.g. DDT, PCBs * radioactive materials * micro-plastics e.g. plastic beads in cosmetics

Question 39

consequences of exceeding the novel entities' boundary

Answer 39

Bioaccumulation in food chains and webs

Question 40

remedial measures taken to deal with the problem of the novel entities' boundary

Answer 40

* Some novel entities are already controlled e.g. the use of DDT is banned. * But of the estimated 100 000 manufactured chemicals and other entities, few have been properly assessed.

Question 41

endangered species

Answer 41

a species whose number and genetic diversity have been reduced to the extent that their long term survival is in doubt

Question 42

planetary boundaries

Answer 42

limits between which global systems must operate to prevent abrupt and irreversible environmental change.