4.4 Water Pollution

Types of Water Pollutants

floating debris, organic material, inorganic plant nutrients (nitrates and phosphates), toxic metals, synthetic compounds, suspended solids, hot water, oil, radioactive pollution, pathogens, light, noise and biological pollutants (invasive species).

Ways to test Water Qualty

pH, temperature, suspended solids (turbidity), metals, nitrates and phosphates.

Turbidity

Measures the amount of sunlight that can reach the water. If there are too much solids on the water surface, this blocks sunlight to the water.

Biodegradation

the ability of organic substances and materials to be broken down into simpler substances. Too much of biodegradation in the water can lead to the formation of toxic gases.

Biochemical oxygen demand (BOD)

a measure of the amount of dissolved oxygen required to break down the organic material in a given volume of water through aerobic biological activity

Euthrophication

Too much plankton grows in bodies of water, resulting in sunlight being blocked in the water.

Biotic Index

indirectly measures pollution by assaying the impact on species within the community according to their tolerance, diversity and relative abundance.

Dead Zones

Areas in water where there isn’t enough oxygen in the water to support organisms