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.