2.  Air pollution - ▪ Measure the acidity of rain water to determine pH ▪ Measure CO 2, CO, or NO x levels in the atmosphere using a gas sensor ▪ Measure particulate matter suspended in the atmosphere

3.  Soil pollution ▪ Test for nitrates and phosphates (Using LaMotte test kits)

4.  Water pollution ▪ nitrate and phosphate tests ▪ fecal coliform tests ▪ tests for heavy metals (Hg, Pb, As)

5.  BOD is the amount of oxygen required to support respiration by organisms living in a water sample. ▪ high BOD indicates there are many organisms using oxygen for respiration ▪ low BOD indicates relatively few organisms needing oxygen for respiration ▪ high BOD = low DO levels = high pollutant levels, especially nitrate & phosphate ▪ low BOD = high DO levels = low pollutant levels

6.  A Biotic Index uses the presence or absence of key organisms to indicate the relative level of pollution in a stream.  Indirect method of measuring pollution  Advantage: Easy to use, especially for moderately or heavily polluted sites.  Disadvantages: not specific enough, doesn’t fully account for habitat quality

7. Semi-Pollution Tolerant Pollution Tolerant Pollution Intolerant

8.  Species that are present either only in polluted areas or only in unpolluted areas.  Lichens – Not present in air pollution  Rat-tailed maggot and sludge worms – Found only in polluted water  Gammarus - small crustaceans that are not found in high levels of salinity.