Measuring Water Quality

Water samples, aerial photography, and aquatic life forms The health of a water body can be determined by analyzing physical, chemical and biological factors How do scientists measure water quality?

How much oxygen is available for organisms to breathe Dissolved oxygen (DO) How much oxygen is available for organisms to breathe What photosynthetic organisms are making/using oxygen pH Measure of chemicals dissolved in water Too high or low can be deadly What chemical factors are used to measure water quality?

Too many can stimulate algal growtheutrophication Toxins Nutrients NPK Too many can stimulate algal growtheutrophication Toxins Metals, pesticides, oils, etc What chemical factors are used to measure water quality?

Dictates what life forms can survive Temperature Dictates what life forms can survive Correlated to the amount of direct sunlight Warmer water contains less DO than cold water Amount and speed of water Some water is slow moving or even stagnant, where as obstructions or curved paths can create rapids What physical factors are used to measure water quality?

Large sediments stir up more water, increasing DO Turbidity (Clarity) Substrate on bottom Large sediments stir up more water, increasing DO Turbidity (Clarity) How much solid is being carried in the bedload What physical factors are used to measure water quality?

Living things that provide information about water quality Pathogens Viruses and bacteria (fecal coliforms), mostly from failing septic systems, untreated human waste, and animal waste Bioindicators Living things that provide information about water quality Fish, plants, and macroinvertebrates (snails, worms, larvae) Only species most tolerant will be found in heavily polluted waters What biological factors are used to measure water quality?