1. pH TURBIDITY Water Quality Factors TEMPERATURE DISSOLVED OXYGEN (DO)
NITRATES & PHOSPHATES
BIO-
INDICATORS pH

2. TEMPERATURE
Temperature – a measure of the warmth or coldness of an object
In science we use the Celsius scale
0ºc (water’s freezing point) – 100ºc (water’s boiling point)
healthy water systems have cool or cold temperatures

3. TEMPERATURE EFFECTS OF TEMPERTURE CHANGES:
changes rate of photosynthesis and respiration
changes DO in water
cold water holds more DO
hot water holds less DO
changes sensitivity of organisms to toxic
waste, parasites, disease.

4. TEMPERATURE CAUSES OF TEMPERATURE CHANGES:
Thermal pollution = adding warm water to cold water.
CAUSES OF THERMAL POLLUTION:
Industry (nuclear power plants, paper mills)
Urban Development (storm water runoff, construction, soil erosion)

5. DISSOLVED OXYGEN (DO)
Dissolved Oxygen – the amount of oxygen dissolved in a body of water
comes from algae and plants
related to temperature: colder waters hold more oxygen
healthy water systems have high levels of dissolved oxygen

6. DISSOLVED OXYGEN (DO) ORANGE = Oxygen MICKEY MOUSE = Water
Less Oxygen =
Less fish
Fish need
Oxygen

7. ORGANIC WASTE = LOW DO Organic waste = parts of once living things
EXAMPLES OF ORGANIC WASTE:
Sewage
Farm runoff
Discharge from food processing plants
How does raw sewage lower the dissolved oxygen?

8. HEALTHY POND

9. RAW SEWAGE IS DUMPED

10. UNHEALTHY POND

11. HOW RAW SEWAGE LOWERS DISSOLVED OXYGEN
Raw Sewage goes onto water
Decomposers chow down
Decomposers take up oxygen
Decomposers reproduce, taking up more oxygen
No more oxygen for other animals
Nothing left but decomposer & sewage-filled water.

12. pH pH – the measure of how acidic or basic something is
Draw the pH Scale
healthy water systems have a pH around 7.0 ( )
low pH comes from acid rain
high pH comes from over growth of algae

13. pH
pH scale
*Alkaline = Basic

14. pH Acids • Taste Sour • Are Corrosive to Metals
• Turn pH Paper and Universal Indicator Red
• No Change in Phenolphthalein
Examples
Hydrochloric Acid
Orange Juice
Vinegar
Aspirin
Bases
• Used as cleaning products
• Taste Bitter
• Feel Slippery
• Turn pH Paper and Universal Indicator Blue
• Turn Phenolphthalein Pink
Ammonia
Bleach
Baking Soda
Sodium Hydroxide
Neutrals
pH of 7.0 only
Milk
Distilled Water

15. pH

16. NITRATES and PHOSPHATES
Nitrates and Phosphates – nitrogen compounds and phosphorous compounds used for growth by plants or algae normally found in fertilizers
nitrates and phosphates in water usually come from fertilizer runoff
healthy water systems have low levels of nitrates and phosphates

17. NITRATES and PHOSPHATES
high nitrate and phosphate levels can cause an algal bloom (large quick algae growth) and increase turbidity, decreasing dissolved oxygen, and killing fish
In extreme conditions this leads to eutrophication of the water system

18. NITRATES or PHOSPATES
OUR HAPPY POND IS
NOW “DEAD”

19. NITRATES AND PHOSPATES
Eutrophication Process
Nitrates and Phosphates feed algae
Algae grows & grows
Algae blocks sunlight
Underwater plants die
Algae die and decompose
The decomposition takes up oxygen
No DO for organisms, so they die
Dead material piles up in filling in the lake

20. EUTROPHICATION

21. NITRATES and PHOSPATES

22. TURBIDITY
Turbidity – the measure of how clear water is the higher the turbidity the more unclear the water (caused by solids blocking sunlight)
measured with a secchi disk
healthy water systems have low turbidity
silt, sediment, algae, and runoff increase turbidity levels

23. TURBIDITY
if turbidity is high no photosynthesis can occur and can clog the gills of fish
related to temperature: high turbidity causes high temperatures

24. TURBIDITY

25. TURBIDITY

26. BIO-INDICATORS
Bio-indicators – organisms or parts of organisms that are used to determine the health of an ecosystem
pollution intolerant organisms cannot live in the presence of pollution
pollution tolerant organisms can survive and thrive in the presence of pollution
healthy water systems have mostly pollution intolerant organisms
if pollution tolerant organisms are found then water quality is low

27. BIO-INDICATORS HOW HUMANS AFFECT BIO-INDICATORS: Over-fishing
Industrial pollution
Poor farming practices
Adding foreign species

28. BIO-INDICATORS