1 / 24

Probes/kits used in testing the water quality

Probes/kits used in testing the water quality. 2014 Group 4 Project. pH. Why is pH important?. pH is an important indication of water quality. Aquatic organisms are sensitive to the pH of their environment.

lilith
Download Presentation

Probes/kits used in testing the water quality

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Probes/kits used in testing the water quality 2014 Group 4 Project

  2. pH

  3. Why is pH important? • pH is an important indication of water quality. Aquatic organisms are sensitive to the pH of their environment. • A pH range of 6.5 to 8.2 provides the optimum conditions for life of freshwater fish and bottom dwellers.

  4. Factors that Affect pH Levels • Acidic rainfall • Algal blooms • Level of hard-water minerals • Releases from industrial processes • Carbonic acid from respiration or decomposition

  5. Vernier pH ProbeStreams and lakes are often basic, with pH values between 7 and 8

  6. Turbidity

  7. TurbidityTurbidity is a measure of water’s lack of clarity. Water with high turbidity is cloudy, while water with low turbidity is clear. Sources of Turbidity • Soil erosion • Urban runoff • Industrial waste • sewage treatment effluent • particulates • Abundant bottom-dwellers • Microorganisms • decaying plants and animals

  8. Why Turbidity is important?Decreases photosynthetic rateIncreases water temperatureCausing oxygen levels to fall. VERNIER TURBIDITY PROBE

  9. Vernier Turbidity Probe • Water is visibly turbid at levels above 5 NTU. • Drinking water ranges between 0.5 to 1 NTU.

  10. Temperature

  11. Temperature • The temperature of a body of water influences its overall quality. • One important aspect of water temperature is its effect on the solubility of gases, such as oxygen.

  12. Factors that Affect Water Temperature • Air temperature • Amount of shade • Soil erosion and increasing turbidity • Thermal pollution from human activities

  13. Water Temperature influences • The amount of dissolved oxygen (DO) • Rate of plant growth • Metabolic rate of organisms

  14. Vernier Temp. Probe

  15. Dissolved Oxygen (DO)

  16. Dissolved Oxygen • Oxygen dissolved in water is vital to the existence of aquatic organisms (cellular respiration) • The concentration of dissolved oxygen, DO, is an important indicator of the water quality.

  17. How does Oxygen enter into the water?Diffusion of Oxygen from atmosphereAeration of water - water moves over rocks and debris - wind and wavesPhotosynthesis by aquatic plants Factors that affect DO levels • Temperature • Aquatic plants • Decaying organic material in water • Stream flow • pressure • Human activities

  18. Vernier DO Sensor

  19. Biochemical oxygen Demand (BOD) • BOD is a measure of the quantity of oxygen used by microorganisms (e.g., aerobic bacteria) in the oxidation of organic matter. • When nutrients and sunlight are overly abundant due to human influence, BOD is increased. • Oxygen consumed in the decomposition process robs other aquatic organisms of the oxygen they need to live.

  20. Measuring Biochemical Oxygen Demand (BOD) • After 5 days of incubation in the dark at 20oC, the BOD bottles are unsealed and the final dissolved oxygen (DO) concentrations are read. • The difference between the initial and final concentrations,

  21. Total Dissolved Solids • Solids are found in lake waters, both suspended and dissolved. • Suspended solids include silt, stirred-up bottom sediment, decaying plant matter, run offs or sewage effluent. • Dissolved solids include salts that yield ions such as sodium (Na+), calcium (Ca2+), magnesium (Mg2+), bicarbonate (HCO3–), sulfate (SO42– ), or chloride (Cl– ). • Total dissolved solids, or TDS, can be measured using a Vernier Conductivity Probe.

  22. Effects of high total solids • Can be harmful to aquatic organisms • Reduce water clarity (increased Turbidity) • Aesthetically unpleasing • Decrease photosynthetic rate • Increase water temperature

  23. Vernier Conductivity Probe

More Related