A partnership of a fungus and an alga or bacterium

Why are lichens good pollution indicators?

They absorb pollutants from the air

What was a lichen desert?

A polluted city area with few lichens

What was created in England in 1970?

A scale linking lichens to sulfur dioxide levels

Lichen Air Quality Quiz: Living Indicators of Clean Air

This lichen air quality quiz reads the crusts and tufts on tree bark like a pollution report. Play 10 interactive questions on why lichens absorb pollutants from air and rain, their sensitivity to sulfur dioxide, lichen deserts in old industrial cities, bushy, leafy and crusty forms, a 1970 scale for England, recovery as air cleaned up and orange lichens that thrive on nitrogen.

Start Lichen Air Quality Quiz

🎯 Daily Trivia Challenge • 🧠 10 Questions • ⏱️ 150 Seconds

Question 1 / 10 Time: 150s

What
What is a lichen?
Absorb
How do lichens get water and nutrients?
Why
Why are lichens good pollution indicators?
Gas
Which pollutant historically harmed lichens most?
Desert
What was a lichen desert?
Forms
Which lichen form is usually most sensitive to pollution?
Scale
What was created in England in 1970?
Return
What happened as air got cleaner?
Nitrogen
Which lichens increase with nitrogen pollution?
Use
How can people use lichens today?

Explanations: answer key for all 10 questions

Q1: What is a lichen?
Answer: A partnership of a fungus and an alga or bacterium
They live as one.
Q2: How do lichens get water and nutrients?
Answer: Directly from air and rain
They lack roots.
Q3: Why are lichens good pollution indicators?
Answer: They absorb pollutants from the air
They cannot filter them out.
Q4: Which pollutant historically harmed lichens most?
Answer: Sulfur dioxide
It came from coal burning.
Q5: What was a lichen desert?
Answer: A polluted city area with few lichens
Industrial cities had them.
Q6: Which lichen form is usually most sensitive to pollution?
Answer: Bushy, shrub-like lichens
Crusty ones tolerate more.
Q7: What was created in England in 1970?
Answer: A scale linking lichens to sulfur dioxide levels
It let people estimate pollution.
Q8: What happened as air got cleaner?
Answer: Many lichens returned to cities
Clean air acts helped.
Q9: Which lichens increase with nitrogen pollution?
Answer: Some orange lichens
Ammonia from farms favors them.
Q10: How can people use lichens today?
Answer: To survey local air quality
Schools run lichen surveys.

Reading the Air on Tree Bark

Lichens are partnerships of a fungus with an alga or cyanobacterium, living as one. They have no roots and take water and nutrients directly from air and rain. Because they cannot filter out what they absorb, they soak up pollutants too, making them living indicators of air quality.

Sulfur dioxide from coal burning once wiped lichens from many industrial cities, leaving lichen deserts. In 1970, scientists in England created a scale linking which lichens grew to sulfur dioxide levels. Bushy, shrub-like lichens are usually most sensitive, leafy ones intermediate and crusty ones most tolerant.

As clean air laws cut sulfur pollution, many lichens returned to cities. Today some orange lichens thrive where nitrogen pollution, such as ammonia from farms, is high. Schools and volunteers use lichen surveys to check local air.

What This Quiz Teaches

Science fans will enjoy these questions.

What lichens are
Why they absorb pollution
Which pollutants matter
How cities changed
How surveys work

Did You Know?

Lichens grow very slowly.
Some lichens live for centuries.
Reindeer eat lichens in winter.
Lichens make dyes and litmus.
Old churchyards hold rich lichen life.