Water QualityNatural & Controlled

Environments

Monitoring natural

environments

Photo courtesy of Melissa Gutierrez

So who monitors our natural waters?

• Environmental Protection Agency-– Mission- protect human health,

safeguard environment

• Clean Water Act (1972)- law regulating discharges of pollutants into the waters of the United States and regulating quality standards for surface waters

Nitrates (NO3) & phosphates (PO4)

• Run-off from commercial fertilizers and animal waste to near-by storm drains and creeks

• Scale from 0 – 1 ppm

• Can increase algal blooms and aquatic plants hypoxia (low oxygen)

Dissolved oxygen

• necessary for most life• hypoxia lowers tolerance

to stressors (pathogens, pollution, etc.) death

• enters water as a product of photosynthetic organisms & by water/air interactions

• Aquarium O2 = 7-9

Air temperature

• Varies

• Affects water temperature

Which water would

you rather jump

in to?

Water temperature• Varies

• Changes less rapidly than air temperature

• Cold water holds more DO

pH

• Range from 0-14 measuring acidity (< 7) or alkalinity (> 7) of substance

• pH of Water = 7.0

Turbidity

• Secchi disk- Measures transparency of fresh or saltwater

Fecal coliform bacteria

• Coliform bacteria (E. coli) found in feces & intestinal tract of warm-blooded animals

• Its presence may indicate presence of other harmful pathogens

• Animal waste washes into bodies of water after heavy rains

The Dead Zone

Hypoxia and anthropogenically increased nitrogen and phosphorus input

World Wide Effects of Eutrophication

Monitoring controlled environments