Water Pollution and Deforestation

Question 1

How does fertiliser cause big problems when it ends up in rivers and lakes?

Answer 1

when the phosphates and nitrates are put onto fields as mineral fertilisers, if too much is applied and it rains then the nitrates are leached into the rivers and lakes which is called eutrophication - causes serious damage to river and lake ecosystems

Question 2

What is another cause of eutrophication?

Answer 2

pollution by sewage - sewage contains a lot of phosphates from detergents and nitrates from urine and faeces

Question 3

What is leaching?

Answer 3

• when trees take up nutrients from the soil before they can be washed away and leached by the rain, but return them to the soil when the leaves die
• when trees are removed nutrients get leached away and aren’t replaced, which leaves infertile soil

Question 4

What is soil erosion?

Answer 4

when the tree roots hold together the soil together and then when the trees are removed, soil can be washed away by the rain which leaves infertile ground

Question 5

What occurs in disturbing evapotranspiration?

Answer 5

it includes both processes of water evaporating from the earth’s surface and from plant transpiration, then the water falls back down to the ground as rain and snow… and then finally when the trees are cut down, evapotranspiration is reduced which makes the local climate drier

Question 6

what happens when we disturb the balance of carbon dioxide and oxygen?

Answer 6

when we cut down trees and burn them rather than them storing the carbon dioxide it is al produced at once which contributes to global warming and if there are fewer trees there is less photosynthesis which means less oxygen meaning the levels of oxygen to drop in the atmosphere creating unevenness