assessing pollution

• Indicator species are used to investigate the presence and absence of pollution.
• Water pollution:

  • Stonefly larvae & freshwater shrimps are highly sensitive to the concentration of dissolved oxygen.
• Air pollution:

  • Lichen are highly sensitive to sulfur dioxide concentrations.
• Pros & cons:

  • simple and cost effective

  • no accurate quantitative figures on how much pollution

  • might be factors other than pollution
• Dissolved oxygen metres and chemical/lab tests.