3. - Environment - Climate - Landscape - Land use - Local Population (animals and humans) Depends on…

4. We all need oxygen! Oxygen mixes with water in streams, rivers and oceans Waterfalls, rapids, waves High Oxygen = Healthy Ecosystem

5. Fertilizer Run-off Sewage Decaying plants Temperature Increase Tumbling over rocks, rapids and waterfalls Water mixed by waves and wind Aquatic plants and algae Temperature decrease

6. Measurement of relative acidity Ranges from 0 to 14 Below 7 are acidic Above 7 are basic At 7 are neutral Influenced by: Type of rocks and soil that it flows through Reacts with alkaline soils and minerals

7. Acid Precipitation Mine Drainage Industrial Waste Decaying Plants Water flowing through alkaline soils and minerals Rapidly growing plants and algae Industrial wastes

8. Form of Nitrogen= fertilizer for plants Streams normally have low levels of Nitrates Elevated Nitrate levels can cause: Excessive plant growth-> Large amounts of decay use up oxygen -> Fish and animals suffocate EUTROPHICATION Unsafe drinking water

9. Natural water has very low levels Fertilizer run-off Wastewater from sewage treatment plants

10. Salinity is the amount of dissolved salts in water Distribution of plants and animals depends on salinity Freshwater life= low/no salt 0.5ppt Brackish water= mix of salt and fresh Saltwater life= higher levels of salt 35 ppt

11. Fresh water has very low levels Sea water Tides mix salt water with freshwater Run-off from road salt

12. Affects: Amount of Dissolved Oxygen Rate of photosynthesis Sensitivity of organisms- small changes can cause death for some animals Thermal pollution- adding warm water to river Industries use water to cool machines and warm water goes back into river

13. Ground water Shade Sunlight reaches the water Industry and power plants Run-off from warm buildings and parking lots

14. Chemical testing: Dissolved oxygen pH Nitrate Salinity Take a Sample Add Testing Tabs Compare Results

15. Macroinvertebrates = aquatic insects, worms and crustaceans Can be used to determine water quality Some can only live in clean water Some can live in polluted water