temperature dissolved oxygen (do) oxygen (do) ph nitrogen phosphates turbidity bio- indicators water...
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TEMPERATURETEMPERATURE
DISSOLVEDDISSOLVEDOXYGEN (DO)OXYGEN (DO)
pHpH NITROGENNITROGEN
PHOSPHATESPHOSPHATES
TURBIDITYTURBIDITY
BIO-BIO-INDICATORSINDICATORS
Water Quality FactorsWater Quality Factors
TEMPERATURE
EFFECTS:changes rate of photosynthesischanges rate of respirationchanges DO in water
cold water holds more DOhot water holds less DO
changes sensitivity of organisms to toxic waste, parasites, disease.
TEMPERATURE
• 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)
DISSOLVED OXYGEN (DO)
ORANGE = Oxygen
MICKEYMOUSE = Water
Fish needOxygen
Less Oxygen =Less fish
DISSOLVED OXYGEN (DO)
TO INCREASE DO:
• Much of DO comes from atmosphere
• Some of DO comes from photosynthesis
TO DECREASE DO:
• Add pollution
• Add organic waste
ORGANIC WASTE = LOW DO
• Organic waste = parts of once living things
EXAMPLES OF ORGANIC WASTE:
Sewage
Farm runoff
Discharge from food processing plants
HOW RAW SEWAGE LOWERS DO
RAW SEWAGE GOES INTO WATER:
1. Decomposers chow down
2. Decomposers take up oxygen
3. Decomposers reproduce, taking up more oxygen
4. No more oxygen for other animals
5. Nothing left but decomposer & sewage-filled water.
HEALTHY POND
RAW SEWAGE IS DUMPED
UNHEALTHY POND
pH
• pH = measure of concentration of hydrogen ions in a substance
• Tells whether substance is:
ACID
BASE
NEUTRAL
pH
Measured on scale from 0 to 140 = highly acidic (HCl)7 = neutral (pure water)14 = highly basic (bleach)
Seawater pH ranges from 7.5 – 8.5Average pH of ocean water = 7.8pH of natural water = 6.5 – 8.5Optimal range for life = 6.5 – 8.2
pH
US Northeastern rain pH = 4.3
Rain elsewhere in US pH = 5.0 – 5.6
pH
pHSOURCES OF LOW pH IN WATER:
• Acid rain is cause of acid in thousands of lakes
• Burning fossil fuels has increased acid rain
EFFECTS OF LOW pH IN WATER:
• Low pH directly kills fish
• pH < 5, most fish eggs die
NITROGEN
• Living organisms need nitrogen to make proteins
• Nitrates (NO3) & Nitrites (NO2) are compounds made of nitrogen & oxygen
• Some nitrogen in water is good
• The wrong amount is bad
NITROGEN
SOURCES OF NITROGEN IN WATER:
Human & animal waste
fertilizer
EFFECTS OF TOO MUCH NITROGEN:
Lowers dissolved oxygen (DO).
NITROGEN – EUTROPHICATION
Q: How does Nitrogen reduce the amount of DO?A: Eutrophication• Nitrogen feeds algae (green stuff)• 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
NITROGENNITROGEN
OUR HAPPY POND IS OUR HAPPY POND IS NOW “DEAD”NOW “DEAD”
EUTROPHICATION
NITRATES
PHOSPHATES
• Phosphorus is an element like hydrogen or oxygen
• Phosphorus combines with other things to make phosphates
• Essential for living things
• Usually present in very small amounts
• Too much is bad
PHOSPHATES
SOURCES OF PHOSPHATES IN WATER:
Storm sewer runoff
Soil erosion
Fertilizer
Forest fires
Volcanic eruptions
PHOSPHATES
PHOSPHATES
EFFECTS OF PHOSPHATES:
Eutrophication (same as with nitrates)
PHOSPHATESPHOSPHATES
OUR HAPPY POND IS OUR HAPPY POND IS NOW “DEAD”NOW “DEAD”
EUTROPHICATION
PHOSPHATES
TURBIDITY
• Measures clearness of water
• Murky water = greater turbidity
• Caused by solids blocking sunlight
• Measured using a Secchi disk or turbidity meter
TURBIDITY
TURBIDITY
HUMAN DUMPING:
Clay
Silt
Industrial waste
Raw sewage
SOURCES:
Human dumping
Construction
Soil erosion
Nitrate pollution
Phosphate pollution
TURBIDITY
EFFECTS:
Clogs fish gills
Smothers eggs
Makes water unlivable
BIO-INDICATORS
• Bio-indicators = organisms that help determine health of water.
• Presence or absence tells something about the water.
• Not always an accurate way to measure water quality.
• Accurate in telling environmental stress
BIO-INDICATORS
HOW HUMANS AFFECT BIO-INDICATORS:
Over-fishing
Industrial pollution
Poor farming practices
Adding foreign species
BIO-INDICATORS
BIO-INDICATORS
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