Human influences

Question 1

Pollution

Answer 1

upsetting the natural balanced habitats by the introduction of new materials or excess amounts of existing ones.

Question 2

How human activites release greenhouse gas

Answer 2

• Water vapour:from rivers
• Carbon dioxide:deforestation
  -Nitrous oxide:fertillisers
• Methane:cattle
• CFC’s:refridgerators

Question 3

How sulfur dioxide causes acid rain

Answer 3

• releases when fossil fuels are burnt
  -Dissolves in water droplets in clouds to form dilute sulfuric acid which creates acid rain
• acid rain makes rivers too acidic, which leads to aquatic organisms dying

Question 4

Consequences of acid rain

Answer 4

• it corrodes metal and limestone in buildings
• it leeches minerals out of soil so plants and trees cannot survive

Question 5

How is carbon monoxide released

Answer 5

• Released when fossil fuels are burnt through incomplete combustion

Question 6

Dangers of carbon monoxide

Answer 6

-Binds irreversibly to haemoglobin, which then reduces the oxygen carrying capacity of red blood cells.
-This can lead to tiredness,unconscious or even death in severe cases
- in pregnant women, insufficient oxygen affects the growth of foetus

Question 7

Greenhouse gas

Answer 7

gases that absorb infrared radiation from the Sun,trapping it above thee Earth’s surface (greenhouse effect) which leads to the increase of the earths temperature

Question 8

Greenhouse effect

Answer 8

When greenhouse gases absorb infrared radiation and are trapped above the earths surface

Question 9

why the greenhouse effect is neccesary for life on earth

Answer 9

Keeps the earth at livable temperatures making sure it doesn’t get too cold naturally. But the burning of greenhouse gases adds to the greenhouse effect making the earth warmer than normal causing ice caps to melt and sea levels to rise as well as warmer weather

Question 10

How can sewage end up polluting water ways?

Answer 10

• Sewage is rich in minerals and nutrients that allow decomposers and algae to thrive
• decomposers respire aerobically to break down sewage, which uses oxygen
• sewage may also contain bacteria that also respire aerobically
• The algae bloom stops light from reaching aquatic plants causing them to die
  -The bacteria breaking down the plants deplete all oxygen causing other organisms to die

Question 11

sewage treatment

Answer 11

a lot of oxygen is provided by stirring the waste with injecting jets

Question 12

How fertilisers can end up polluting waterways

Answer 12

Eutrophication
- The excess nutrients that are washed away run off into streams encouraging rapid growth of algae

Question 13

eutrophication

Answer 13

when fertilisers are run off from the land into nearby rivers and lakes by the rain
- The excess nutrients that are washed away run off into streams encouraging rapid growth of algae
- These algae prevent sunlight reaching plants causing them to die and decompose , the decomposing plants bacteria respire aerobically causing oxygen depletion and then all other organisms to die

Question 14

Deforestation

Answer 14

The clearing of trees on a mass scale

Question 15

reasons for forest clearing

Answer 15

• cattle farming
• palm oil
  -Sugar cane
  -housing

Question 16

how deforestation causes Leaching

Answer 16

Trees normally take up nutrients and minerals from the soil to use for growth. without the trees, the nutrients run off into the lake.

Question 17

How deforestation causes soil erosion

Answer 17

Tree roots help to stabilise the soil, without trees the soil will be washed away by the rain

Question 18

Disturbance to the water cycle

Answer 18

Transpiration from trees release water vapur which contributes to the water cycle and the carbon cycle

Question 19

How deforestation =global warming

Answer 19

removal and burning of trees will result in more atmospheric carbon dioxide levels and lower oxygen levels meaning more gas trapped in the earths surface

Question 20

negative effects of deforestation

Answer 20

• Leaching
• soil erosion
• habitat disruption
• disruption of the carbon cycle
• Less CO2 taken out of the atmosphere

Question 21

Leaching

Answer 21

When trees are cut down and their nutrients leak into water ways. Large quantities can cause algal blooms

Question 22

evapotranspiration

Answer 22

provides trees with lots of water thro evaporation and transpiration

Question 23

effect of deforestation on evapotranspiration?

Answer 23

• less trees = less evapotranspiration
• less water will be returned to the atmosphere as quickly
• causes areas to dry up