1. Water Chemistry

2. In your notes… What 3 factors play a role in determining the health of an ecosystem? What 3 factors play a role in determining the health of an ecosystem? What is your definition for polluted water? What is your definition for polluted water?

3. Water Quality Water quality of ecosystems is dependent on chemical, physical, and biological factors. Water quality of ecosystems is dependent on chemical, physical, and biological factors. When substances in water are harmful to the organisms that live there, the water is considered polluted. When substances in water are harmful to the organisms that live there, the water is considered polluted.

4. Dissolved Oxygen (Chemical) Dissolved Oxygen known as “D.O.” This is the most important chemical requirement for aquatic organisms. Diffusion- Water mixes with air when it falls over rocks and waterfalls increasing the level of D.O. Standing or slow moving bodies of water have less D.O. than fast moving water bodies. Example

5. Which likely has more D.O. and why?

6. DO Continued Photosynthesis increases D.O. as respiration by aquatic animals decreases it. (remember the carbon-oxygen cycle?) Photosynthesis increases D.O. as respiration by aquatic animals decreases it. (remember the carbon-oxygen cycle?) Water polluted with organic matter has less D.O. than clean water because decomposers of the organic matter use up the D.O. Water polluted with organic matter has less D.O. than clean water because decomposers of the organic matter use up the D.O. Most fish cannot live with D.O. less than 5 ppm. Most fish cannot live with D.O. less than 5 ppm. Low- 0-5 ppm, Medium- 6-10 ppm, High- 11-15 ppm Low- 0-5 ppm, Medium- 6-10 ppm, High- 11-15 ppm What about the fish tank. What adds DO, and what takes it away? What about the fish tank. What adds DO, and what takes it away?

7. Temperature (Physical) As temp. increases less D.O. can be held in water. As temp. increases less D.O. can be held in water. Trout require high levels of D.O. which is why they live in coldwater streams. Trout require high levels of D.O. which is why they live in coldwater streams. Example ExampleExample

8. Temperature Con’t Thermal pollution occurs when industries (power plants) use water for cooling. Thermal pollution occurs when industries (power plants) use water for cooling. The hot water is dumped into aquatic systems raising the temperature. The hot water is dumped into aquatic systems raising the temperature. Why does this harm wildlife in the stream? Why does this harm wildlife in the stream? What type of plant is this, and where does the hot water come from? What type of plant is this, and where does the hot water come from?

9. Turbidity (Physical) It is the measure of the amount of light scattered or absorbed by particles in water (cloudiness). It is the measure of the amount of light scattered or absorbed by particles in water (cloudiness). Eroded soil in water increases turbidity, clogs fish gills, and smothers aquatic insects. Eroded soil in water increases turbidity, clogs fish gills, and smothers aquatic insects. Example Example

10. Which has more turbidity?

11. pH (Chemical) Few aquatic organisms can live in water with pH lower than 4 or higher than 9. Few aquatic organisms can live in water with pH lower than 4 or higher than 9. Best range: fish 6.7 - 8.6 Best range: fish 6.7 - 8.6 Example Example Example

12. pH Continued CO 2 produced from decaying organisms forms carbonic acid decreasing pH. CO 2 produced from decaying organisms forms carbonic acid decreasing pH. Sulfuric acid in water comes from acid mine drainage and acid rain (burning fossil fuels) decreasing pH. Sulfuric acid in water comes from acid mine drainage and acid rain (burning fossil fuels) decreasing pH. Alkaline industrial waste (bleaching plant) can increase pH. Alkaline industrial waste (bleaching plant) can increase pH.

14. Hardness (Chemical) Water with many minerals is considered hard. Water with many minerals is considered hard. Water containing calcium and magnesium is said to be hard. Water containing calcium and magnesium is said to be hard. The minerals in hard water can buffer acidic rain water. The minerals in hard water can buffer acidic rain water. Calcium is needed for clams, snails, and other shelled organisms. Calcium is needed for clams, snails, and other shelled organisms. Soft: 0 - 60 ppm Soft: 0 - 60 ppm Medium: 60 – 120 ppm Medium: 60 – 120 ppm Hard: 120 – 180 ppm Hard: 120 – 180 ppm

15. Nitrites/Nitrate (Chemical) Runoff of fertilizers, animal wastes, and sewage are the major sources. Runoff of fertilizers, animal wastes, and sewage are the major sources. EUTROPHICATION- Excessive nitrogen causes algae population to explode (algae bloom). EUTROPHICATION- Excessive nitrogen causes algae population to explode (algae bloom). Most nitrogen is constantly used up in the system. Most nitrogen is constantly used up in the system. More than 1 ppm indicates excess! More than 1 ppm indicates excess! When the algae dies it decomposes using up the D.O. When the algae dies it decomposes using up the D.O.

17. Phosphates (Chemical) Comes from the same sources as nitrogen as well as some industrial processes. Comes from the same sources as nitrogen as well as some industrial processes. Used in Laundry Detergent Used in Laundry Detergent Also causes algae blooms. Also causes algae blooms. Not as harmful to humans or animals as nitrogen. Not as harmful to humans or animals as nitrogen. More than 0.5 ppm indicates excess. More than 0.5 ppm indicates excess.

18. Hurricane Floyd

21. 2.5 billion gallons hog/poultry waste

23. Dead Zones