The following heavy metals is toxic and poisonous at low concentration except:

• Pb

• Hg

• Zn

• Cd

The process when concentrations of a harmful substance increases in organisms at higher trophic levels in a food chain or food web.

• Bioaccumulation

• Biodegradable

• Euthrophication

• Biomagnification

Eutrophication causes a reduction in

• Dissolved oxygen

• Nutrients

• Nitrogen and Phosphorus

• All of these

Which of the following would be considered water pollution from a non-point source?

• chemical from a factory entering a stream through a drain pipe

• sewage leaking into a lake from a treatment plant

• agricultural pesticides leaded into ground water from a storage area

• residential runoff contributing to poor water quality

These are the physical parameters of water quality except

• BOD

• Turbidity

• Temperature

• Taste

In which of the following zones would you expect fish to be absent?

• Septic zone

• Clean zone

• Decomposition zone

• Recovery zone

The biological oxygen demand (BOD) test is designed to directly measure

• how rapidly the water is moving

• amount of oxygen required to decompose organic matter in water

• the amounts of nitrites in the water

• amount of oxygen required to chemically oxidize the organic material and inorganic nutrients present in water

What is the effect of an increase in BOD?

• alga bloom occurs

• aquatic organisms die

• bacteria decomposes

• None of above

We can prevent water pollution by:

• Reduce the use of plastic.

• Properly dispose of chemicals.

• Do not apply fertilizer or pesticides near a body of water.

• All of above.

Chemical oxygen demand (COD) is the water quality parameter to measure how clear of the water body.

• True

• False