Guzmán 4/21/14

Dissolved Oxygen The amount of oxygen gas dissolved in liquid water Essential for maintenance of healthy lakes and rivers because all animals need oxygen to survive. High levels = good, low levels = bad Sources come from churning water and aquatic plants

Fecal Coloform Bacteria found in the feces of humans and other animals Enter water from direct discharge, agricultural runoff, storm runoff, or human sewage discharged into water These bacteria themselves are not harmful, but will indicate the presence of other possibly harmful disease causing organisms Enter the body through cuts, nose, mouth, or ears. Can cause typhoid fever, hepatitis, gastroenteronitis, dysentery, and ear infections. Some coloform bacteria in water is completely normal

pH Measures how acidic (more H ions than OH) or how basic (less H ions than OH) there is in water Normal = 6.5 to 8.5 Increased SO2(sulfur dioxide) and NOx (nitrogen oxides) are converted into acid and increase acidity of water by mixing with water vapor and coming down as acid rain. Common sources = auto exhaust, coal-power plant emissions

Temperature Temperature is a factor in how much oxygen can be dissolved (cool holds more) Reasons why water might be warmer: Adding hotter water from factories or nuclear power plants Runoff from concrete/blacktop is warmer than natural surfaces Cutting down trees eliminates shade Adding soil or dark debris from erosion attracts more sunlight Erosion collects at bottom, making streams wider and more shallow. Heats up easier.

Temperature (cont.) Most of the physical, biological and chemical processes of water are related to temperature Ex: how much oxygen can be dissolved (cool holds more) Higher temps make photosynthesis rates increase > more plants > more plant death > more bacteria decomposing > less available oxygen for aquatic organisms Fish get “stressed” and get sick easier when it’s warmer High levels = bad, low levels = good

Phosphates A group of compounds containing the element phosphorous. Needed for plant and animal survival. Comes from organic sources such as animal waste, human waste, vegetation, etc. Can also come from detergents Fertilizers used for crops or lawns usually contain phosphorous. Too much will cause overgrowth of plants called eutrophication High levels = bad, low levels = good

Nitrates NO3 Needed by all plants and animals for survival Used as a fertilizer and can eventually lead to eutrophication Sewage is the main source High levels = bad, low levels = good

Turbidity Measure of how cloudy or clear water is Cloudy water indicates erosion Cloudy water attracts more sunlight and can lead to thermal pollution High levels = bad, low levels = good

Total Solids Similar to turbidity, but also includes dissolved solids High levels = bad, low levels = good