Eutrophication
Biology: Edexcel IGCSE, topic 5.2.2
Eutrophication
Eutrophication happens when untreated sewage or excessive fertiliser enters water sources from the land. This causes the availability of nitrates and other ions in the water to increase. The consequences of this are:
Increased growth of producers
- Very fast growth spurts, or 'blooms', of algae is common.
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Increases the rate of decomposition
- Eutrophication increases the rate of respiration of decomposers.
- This means that producers decompose more quickly.
- This leads to a lower level of dissolved oxygen in the water (because decomposers use up the oxygen).
- Organisms that need oxygen can't then respire, so they die.
Test yourself on Eutrophication
Consequences of eutrophication
What do we call the outcome of excessive fertiliser entering watercourses from the land?
Which of the following is not a consequence of eutrophication?
Eutrophication