Assessing Pollution Flashcards
All 7 cards in this deck
What is an indicator species?
A species whose presence, absence or abundance indicates the level of pollution in an environment.
Which two named invertebrates indicate polluted water with low oxygen?
Bloodworms and sludgeworms.
Which two named invertebrates indicate clean, well-oxygenated water?
Freshwater shrimps and stonefly (nymphs).
Which organisms are used as indicators of air quality?
Lichens (different species tolerate different sulfur dioxide levels) and blackspot fungus on roses.
True or false? Lots of lichen species growing on trees indicates high levels of sulfur dioxide in the air.
False. A wide variety of lichens indicates clean air; polluted air leaves few or no lichen species.
Give one advantage and one limitation of using indicator species instead of chemical measurement of pollution.
Advantage: cheap, quick and shows the long-term effect of pollution on living things. Limitation: only gives a rough estimate, not the actual concentration of the pollutant, and other factors (e.g. temperature, disease) can affect the species.
How do you use indicator species data to judge water pollution?
e.g. a stream sample contains many sludgeworms and no stonefly nymphs
- Identify which indicator species are present and absent.
- Match them to their pollution tolerance: sludgeworms tolerate pollution, stonefly need clean water.
- Conclude the pollution level: the stream is polluted with low oxygen.