Lecture 3

Question 1

Why are nutrients considered pollutants, since they are required for life?

Answer 1

Excess nutrients can cause major problems in aquatic environments

Question 2

What causes nutrient pollution to be such a worldwide problem?

Answer 2

Agricultural runoff - animal manure, fertilizers, soil erosion and domestic sewage

Question 3

What is eutrophication

Answer 3

Eutrophication is an enrichment of water by nutrient salts that causes structural changes to the ecosystem

Question 4

What is eutrophic water full of

Answer 4

high nitrates
and phosphates, high algal
abundance

Question 5

What does low oxygen (Hypoxia) cause?

Answer 5

Decline in activity of individuals
decrease in reproduction
Decrease in disease resistance

Question 6

What are some HAB mechanisms?

Answer 6

Natural species dispersal
Human-related factors
Climatic shifts
Increased observation

Question 7

What happens in cases of extreme eutrophication

Answer 7

whole ecosystems may be
subject to hypoxia (dead zones due to low oxygen)

Question 8

What are some Nitrates Regulations

Answer 8

Nitrates Directive aims to control nitrogen pollution
Drinking Water Directive sets a maximum
allowable concentration for nitrate

Question 9

What are the nitrates directive for Ireland?

Answer 9

to set out standards for the management of fertilisers and farmyard wastes
Fertilisers can only be applied beyond a minimum setback distance from water sources
* Farms must have facilities to store a certain minimum amount of manures