Water Quality

Question 1

Dissolved oxygen

Answer 1

The amount of oxygen in the water. Affected by temp. Velocity. Plant life. Pollutants.

More dissolved oxygen is good for the ecosystem, supports more organisms

Question 2

pH

Answer 2

Potential of hydrogen. How acidic or basic a solution is. Ranges from 0 (acidic) to 14. Distilled water is 7, neutral. Scale of 10 fold.

Many organisms are sensitive to pH above 8.5 and below 6.5, bones can get soft, laying eggs is hard, mucus clogs gills.

Question 3

Alkalinity

Answer 3

Amount of negative ions in a solution. As alkalinity increases, so does hardness. Good for neutralizing acid. Acts as a buffer for pH. The more alkalinity, the less likely an organism is to be at risk for changes in pH

Question 4

Hardness

Answer 4

Measure of water chemistry that indicates soluble calcium, magnesium, and iron. The higher their concentrations, the ‘harder’ the water. Does not directly affect pH or Alkalinity. Not an accurate measurement of water quality but leads to biological productivity.

Question 5

Nitrates

Answer 5

Ammonia is a byproduct of decomposition. Bacteria + ammonia = nitrates. High nitrate levels = pollution.

Too many nitrates make algal blooms -> raised temperature, murky water -> low O2 -> dead fish

Question 6

Phosphates

Answer 6

Naturally occurring plant nutrient that’s in detergent, cow feed runoff, and human sewage. Causes algal blooms and depletes O2. Low phosphates is good

Question 7

Chloride

Answer 7

NaCl runs into waterways, chloride enters through human animal and industrial waste and soil leaching.

Kills aquatic vegetation. Damages fish fry and eggs in lakes. Creates chemical barrier in lakes, preventing O2 from going to deeper levels

Question 8

CO2

Answer 8

Bacteria decompose sewage but produce CO2 in the process. If water is bad or animals are dying, daytime O2 is high and nighttime is low bc of photosynthesis and respiration.

More constant levels are good for the ecosystem. Sensitive organisms live in streams.

Question 9

Turbidity

Answer 9

Suspended matter that makes water cloudy and scatters light. Usually eroded soil or sediment. Clogs gills, smothers fish, prevents photosynthesis, buries eggs.

Raises water temp. Steals nutrients and spreads pesticides. Very dangerous

Question 10

Temp.

Answer 10

More oxygen demand with a higher temp bc fish metabolism increases. Cold water is good for D.O.