pollution caused by eutrophication

Question 1

define eutrophication

Answer 1

eutrophication is the enrichment of water with nutrients leading to excessive growth of algae and other plants

Question 2

What happens if there are too many plant nutrients in the water?

Answer 2

the level of dissolved oxygen in the water may also be reduced if the water is overloaded with plant nutrients,

especially nitrate ions (NO3^-) and phosphate ions (PO4^3-)

this is called eutrophication

Question 3

What do excessive volumes of in the water cause eutrophication?

Answer 3

phosphate and nitrate ions

Question 4

What do nitrogen and phosphorus cause a huge increase in? What is this known as?

Answer 4

Nitrogen and phosphorus can cause a huge increase in the amount of certain plant life i.e. algae

This is known as ‘algal bloom’

Question 5

What is algal bloom?

Answer 5

Nitrogen and phosphorus can cause a huge increase in the amount of certain plant life i.e. algae

This is known as ‘algal bloom’

Question 6

as algae do not live for long, what happens when they die?

Answer 6

These algae do not live for long and so when they die they are decomposed by large amounts of bacteria that put a large demand (use up) on the dissolved oxygen

Question 7

How does eutrophication occur artificially? (2)

Answer 7

one way that eutrophication can occur is when artificial fertilizers leach into water supplies, or if sewage from houses or farms enters the water supplies.

Question 8

What is natural eutrophication/explain it?

Answer 8

It occurs mainly in lakes and is caused by gradual increase in nitrogen and phosphorus levels caused by sediments building up in these lakes.

as the nitrate and phosphate levels rise, the plants absorb them and undergo rapid growth