Summary
Pollution is the process by which harmful substances are added to the environment, often due to human activities. Pollutants — substances that cause pollution. Example: Chemical waste and untreated sewage are pollutants.
- Eutrophication — a process where excess nutrients in water bodies lead to excessive algae growth and oxygen depletion. Example: Fertilizers washed into rivers causing algal blooms.
- Indicator Species — organisms used to assess the level of pollution in an environment. Example: Bloodworms indicate polluted water.
- Plastic Pollution — the accumulation of plastic products in the environment that adversely affects wildlife and habitats. Example: Marine animals ingesting plastic debris.
Exam Tips
Key Definitions to Remember
- Pollution
- Eutrophication
- Indicator Species
- Plastic Pollution
Common Confusions
- Confusing natural and human-made pollution sources
- Misunderstanding the role of indicator species
Typical Exam Questions
- What is eutrophication? Eutrophication is the process where excess nutrients in water lead to algae growth and oxygen depletion.
- How do indicator species help in assessing pollution? Indicator species show the presence or absence of pollution by their presence in an environment.
- What are the effects of plastic pollution? Plastic pollution harms wildlife, releases toxins, and enters the food chain.
What Examiners Usually Test
- Understanding of pollution causes and effects
- Ability to explain eutrophication
- Knowledge of how indicator species work
