Transcript Fresh and Saltwater Systems

Fresh and Saltwater
Systems
Topic 1 – A World of Water
How do we depend on water?
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Cells in living organisms depend on water
Ecosystems depend on water
We depend on water for industry
We depend on water for agriculture
We depend on water for our living needs such as sewer and
washing things
Distribution of water on Earth
Water Source
Percentage of Water
Oceans
97.20%
Ice Caps and Glaciers
2.15%
Groundwater
0.63%
Rivers, Lakes, Soil and
Atmosphere
0.02%
TOTAL
100%
Water enough for all?
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Four countries share almost half of all the Earth’s fresh water
Country
Amount of Fresh Water
Brazil
18%
Canada
9%
China
9%
U.S.A
8%
Other Countries
56%
Topic 2 – Earth’s Frozen
Water
After ocean water, the next largest amount of water on Earth is
frozen.
What is a glacier
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A large moving mass of ice and snow
How do glaciers form
1. Snow flakes fall on ground and accumulate
2. Fallen flakes turn to snow grains over time
3. As snow keeps accumulating, pressure turns the snow grains to
ice
Types of Glaciers
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Valley Glaciers – A glacier that forms in a mountain range.
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Continental Glaciers – Occur mostly at the poles and are so thick
that they bury mountain ranges.
Glacial Features
On your own...choose four of the following glacial features and give
its definition as well as drawing a picture to show the feature.
You will have about 15 minutes for this.
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Crevasse
Cirques
Arête
Horn
Moraine
Esker
Erratics
U Shaped Valleys
Glacial Features
1. Crevasse – A fissure or crack in the ice
2. Cirques – Bowl shaped basins in the mountains
3. Arête – A sharp ridge on a mountain
4. Horn – A sharpened peak on a mountain
5. Moraine – Ridge of material left behind by a moving glacier
6. Esker – A winding ridge left behind when a glacier melts
7. Erratics – Huge rock fragments left behind by glaciers
8. U Shaped Valley – Valleys eroded by glaciers that are U shaped
Importance of Glaciers
Take a look at page 384 and get four facts about why glaciers are
important
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Glaciers act as reservoirs of fresh water for drinking water
Feed constant supply of water into rivers
Helps run hydroelectric dams
Used for irrigation of crops
Provides fresh water for cattle ranchers
Influence the water cycle
Provide information about the Earth’s past climate
Topic 3 – Fresh Water
Systems
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Fresh water systems exist as both above ground (surface
water) and below ground (groundwater)
Lakes, Ponds and Wetlands
Lakes – Light does not reach the bottom of a lake
Pond – Light reaches the bottom of a pond...ponds technically can
be larger than a lake as long as light reaches the bottom
Wetlands – These are saturated with water all or much of the time
Streams and Rivers
These are fast flowing waterways...streams however, are smaller than
rivers
Underground Water
Most of the water that falls to Earth, sinks into the ground as ground
water
Watersheds
Watersheds are areas of land that drains water into a body of
water...rivers, lakes, ponds
Watersheds in Alberta
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Waterfall in central and northern areas flows towards the Arctic
Ocean
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East central and southern Alberta
Hudson Bay
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Southernmost area of Alberta
Gulf of Mexico
River Flow Monitoring
River flow monitoring is important because:
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It helps scientists to analyze water quality and to warn people about
floods
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Helps in predicting possible drought conditions
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Helps in designing irrigation projects
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Helps scientists to monitor sediment load in a river
Why is Monitoring Sediment Important
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Some sediment released in fish habitat can carry toxins that can kill
fish
Too much sediment in rivers / lakes can decrease water depth making
navigation by boat difficult or dangerous
Sediment can affect delivery of water as sediment can wear out pumps
and turbines
Allows scientists to monitor affects of farming practices on the
environment as some farming practices put sediments into water
Groundwater Contamination
Groundwater carries with it any contaminants that it encounters
Contamination is put into two categories:
1. Point Sources – places where pollutants come from a small defined area
Ex. Leaking gas tanks, leaking septic tanks, landfills
2. Non-point Sources – places where pollutants come from a large area
Ex. Runoff from farmland
YOU WILL NOW BE WORKING ON
TOPIC 1 TO 3 REVIEW
YOU MAY WORK WITH A PARTNER
Topic 4 – The Oceans
A Sea Full of Salt
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Salt in the sea comes from groundwater that flows across rocks
and minerals on land picking up the salt and then entering the
sea.
Ocean Waves
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Ocean waves start in the open ocean
Waves are very similar to light waves we studied...they have a
crest, trough and wavelength
How Waves Change the Shoreline
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Waves constantly move along shorelines and erode and redeposit
sediments along the shore
How Beaches are Formed
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Waves carry sediments and fragments of rocks
The sediments and rock fragments rub against each other and are
smoothed into smaller pebbles and sometimes sand
Beaches are constantly changing due to the constant action of waves
Tides
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Tides are the rise and fall of the ocean
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Tidal movements occur due to the pull of the moon’s gravity on the
ocean
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Spring Tides are the largest tide changes and happen when the Earth,
moon and sun are lined up
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Neap Tides are small tide changes and happen when the moon is at
right angles to the sun
Ocean Currents
Surface Currents – Surface currents are driven by the wind
Three factors influence the direction of winds and surface currents:
Winds begin as a result of uneven heating of Earth’s atmosphere
2. Rotation of the Earth causes a bending of the currents
3. Currents are forced to turn when the hit the continents
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Warm and Cold Currents
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Warm currents flow from the equator and transfer heat to the
atmosphere
Cold currents flow from the poles and draw heat away from the
atmosphere
Topic 5 – Living in Water
Adaptations for Aquatic Life
Aquatic animals have many adaptations to live in water. They are:
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They use gills to get oxygen from the water
Some animals get their oxygen from the water’s surface
Some animals such as dolphins have lungs to breathe
Animals near shore have special appendages to help them dig in
or stick to the ground
Many water animals use buoyancy to help them move
Many larger aquatic animals have streamlined bodies to help
them move through the water
Some aquatic animals filter their food out of the water
Phytoplankton
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Phytoplankton are microscopic plants
Nearly all marine life depends on this plant to live
They are also important to all life on Earth as they produce oxygen
Nutrient Pollution
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This happens when too many nutrients enter a water system
The extra nutrients cause increase growth of algae
As the algae dies, it falls to the bottom of the water and decomposes
and decomposition uses up lots of oxygen that other animals need.
Therefore other animals that need the oxygen can die.