What is eutrophication?

Eutrophication is a negative impact of the use of fertilisers on aquatic lifeforms. When nutrients from fertilisers (eg nitrate and phosphates) leach from farm fields into the water, this allows fast-growing water plants such as algae to 'bloom'. The large amount of algae in the water will outcompete other plants in the ecosystem, which will then die. The death of these plants, as well as the large amount of algae death, will lead to increased activity from decomposing aerobic microbes. These microbes use up oxygen at a faster rate than can be replaced by photosynthesising water plants, leading to oxygen depletion. Due to the lack of oxygen in the water, aerobic animals (such as fish and invertabrates) will die due to an inability to respire, and the lack of oxygen will also encourage the growth of anaerobic bacteria. These bacteria release toxic waste products such as ammonium and hydrogen sulphide.

PF
Answered by Phoebe F. Biology tutor

3652 Views

See similar Biology A Level tutors

Related Biology A Level answers

All answers ▸

What is a neuron and its function?


Describe the process that allows an action potential to be passed across a synapse in the parasympathetic nervous system.


Explain the difference between spatial and temporal summation at a synapse.


The black mamba’s toxin kills prey by preventing their breathing. It does this by inhibiting the enzyme acetylcholinesterase at neuromuscular junctions. Use your knowledge of muscle contraction to explain how this prevents breathing.


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2025 by IXL Learning