fertilisers

Question 1

why are fertilisers used?

Answer 1

to replace the nitrate and phosphate ions lost from harvesting plants for crops from the nitrogen cycle.

Question 2

what are the 2 types of fertilisers?

Answer 2

natural and artificial

Question 3

natural fertilisers

Answer 3

e.g. manure
usually cheap and free if the farmer has animals.

cons- cannot control exact minerals and proportions of these minerals.

Question 4

artificial fertilisers

Answer 4

inorganic compounds created with specific amounts of minerals.

inorganic compounds are more soluble so can dissolve in the water surrounding the soil- plant can take up more nitrate and phosphate ions

cons- high solubility of minerals means they dissolve in rain and large quantities of minerals are lost

environmental impacts- leaching and eutrophication.

Question 5

leaching

Answer 5

water soluble compounds are washed out and into rivers/ponds

Question 6

eutrophication

Answer 6

nitrogen fertilisers are washed from fields and into rivers/ponds
causes growth of algal blooms, which block light
plants below cannot photosynthesise, so they die.
bacteria within the water respire and break down dead plant matter
increase in bacteria- more oxygen within water used for respiration.

eventually, fish and other aquatic organisms die due to lack of dissolved oxygen within the water.