Measuring environmental change

Question 1

Lots of lichen = clean air. How do we know this?

Answer 1

Power stations and cars produce sulfur dioxide pollution,and lichens can’t live in this condition.

Question 2

Mayfly larvae = clean water. How do we know this?

Answer 2

If there is sewage in a river, this leads to less oxygen in the water, and mayfly larvae cannot live where there isnt much oxygen in the water.

Question 3

Sludgeworms = polluted water. How do we know this?

Answer 3

Sludgeworms live in water without much oxygen.