Topic 8 - Water Pollution and Deforestation (Paper 2)

Question 1

how does deforestation cause leaching?

Answer 1

trees take up nutrients from the soil before they can be washed away and return them to the soil when leaves die
when trees are removed, nutrients are leached away but arent replaced

Question 2

How does deforestation disturb the balance of atmospheric gases?

Answer 2

forests take up carbon dioxide by photosynthesis, store it in wood and release it slowly when they decompose
when trees are cut down and burnt, the stored carbon is released at once
fewer trees in the forest also means less photosynthesis

Question 3

how does deforestation cause soil erosion?

Answer 3

tree roots hold the soil together. when trees are removed, soil can be washed away

Question 4

how does deforestation disturb evapotranspiration?

Answer 4

evapotranspiration included water evaporating from the earths surface and from plant transpiration
this water falls back to the earth as rain
so when trees are cut down, evapotranspiration is reduced