Transcript Document

 What
determines the safety
of a water source and how potable it is?
 Potable – safe for humans to drink
 Biological, physical, and chemical variables

Bill board video
 Bacteria,
viruses, and parasites can
contaminate water
 Come from sewage and animal waste
 Temperature
 Lower
temp = water can hold more O2
 Higher temp = plants grow faster and produce
O2
 Water Movement
 Faster water flow dilutes pollution faster
Turbidity
How
cloudy water is
High turbidity can suffocate fish eggs
and make it hard for fish to breathe
 1.
What type of variable is water
temperature?
 2. Describe how water with high turbidity
would look
 3. What is a biological variable?
 4. Name at least 1 biological variable.
 5. What does the word potable mean?
 6. What type of variable is water movement?
 7. Where do biological variables come from?
 8. What is a physical variable?
 Dissolved
oxygen
 microscopic bubbles of gaseous oxygen (O2)
that are dissolved in water
 Comes from - photosynthesis and the
atmosphere
 DO video
 pH
Measure of the acidity of a liquid
 Indicated using a 0 -14 scale (0=acid) (14 = base)
 Vinegar = 3
seawater = 8.3

 Effects
of High pH
 Water with high pH typically contains large
amounts of dissolved minerals, particularly
calcium and magnesium. These represent the
principal components of "hard" water. The minerals
do not pose a direct health threat, but they cause
other problems, such as scale buildup inside water
pipes, soap scum, and decreased effectiveness of
soaps and detergents.
 Effects
of Low pH
 Acid water with a pH less than 6.5 poses no direct
health threat. However, acidic water tends to
dissolve metals, including lead, copper, zinc, iron,
manganese and other metals commonly found in
household water-supply pipes. This process also
results in corrosion of the pipes.
 Salinity
refers to the amount of salt dissolved in
water
o Takes up space oxygen can’t use
 “a salt is a crime in which one person attacks
and means to harm another person...”

 Choose
a water source (ocean, lake, river, etc)
 Find a specific one you will research
 List specific examples of each of the 3 types of
variables found there
 Describe at least 1 biological variable
 Describe at least 1 physical variable
 Describe at least 1 chemical variables
 Must have a minimum of 4 total
 Ex : The mississippi river has higher salinity
where salt water from the gulf of mexico
creeps up it during periods of low rainfall.
 Salinity
 Temperature
 Dissolved
Oxygen
 pH
 Light
 Nutrients
 Substrate
(base layer)
 Circulation (water movement)
 Animals
that tell us how healthy an
ecosystem is
 Provide an early warning of environmental
damage
 Can’t be too tolerant
 Are
often insects
 3 main types
 Pollution Intolerant
 Pollution Semi-tolerant
 Pollution Tolerant
 Runoff
can carry chemicals or oil
 This can percolate into groundwater
 Humans dump sewage waste into rivers
 This is why U. S. standards were first
introduced in 1914
 Pre
1970
 Worried about microorganisms in water causing
disease
 After 1970
 Worried about pesticides, industrial sludge, and
chemicals
 Write
a story from the perspective of an ocean animal
and be sure to include
1. An event that affects either DO, salinity, or pH
levels in the environment in which you are living.
2. Explain how you found out about the event.
3. Discuss in your story how you (the ocean
animal) were affected by the event and
its repercussions.
4. Include one point source OR one non point source of
pollution
5. Include a biological and physical variable that
affects water sources from the notes (PPT is posted
under tests if you missed any of it)
 Include at least 3 illustrations – must include color
(may use construction paper I will provide)

I am a dolphin living off the coast of Georgia. I live
near a delicious smelling breakfast making factory. One
day, the plant workers were throwing a party to
celebrate St. Patrick’s day when they left the machines
unattended and the large coffee making section of the
plant exploded. 250,000 gallons of scalding hot coffee
were released into the ocean near my home. This
decreased the pH level of the ocean because coffee is
acidic. It also increased the water temperature, so the
DO levels went down and my family was forced to
evacuate from our home. We found out about what
happened because my brother likes to play close to the
drainage pipe from the factory. The coffee was such a
major point pollution source that our home was
uninhabitable for weeks and we had to go stay with
some cousins who live in Florida. When we got to their
house, my mom got sick because she was not used to
the bacteria that they have in Florida in the river
where my cousins live. Fortunately She did not stay sick
for long because the river had a fast current, and
would carry the bacteria away as soon as it would grow.