Transcript File - Ms. D. Science CGPA

Land, Air, and Water Resources
Ms. De Los Rios
7th Grade
Ch. 8.3 Surface Water and Groundwater
Essential Question:
How Do People use Earth’s Resource?
What is a River System?
How do Ponds and Lakes From and Change?
How Does Water Move Underground?
Surface Water and Groundwater
Pg. 270-279
Resources
Pearson art in action
Braipop Groundwater
Brainpop Water Supply
Eutrophication youtube
Vocabulary
1.
2.
3.
4.
5.
6.
Tributary-a stream or river that flows into a larger river.
Watershed-the land area that supplies water to a river system.
Reservoir-a lake that stores water for human use.
Eutrophication-the buildup over time of nutrients in freshwater lakes and ponds
that leads to an increase in the growth of algae.
Permeable-characteristic of a material that contains connected air spaces, or
pores, that water can seep through easily.
Impermeable-a characteristic of materials, such as clay and granite, through which
water does NOT easily pass.
7. Unsaturated Zone- the layer of rocks and soil above the water table in which the
pores contain air as well as water.
8. Saturated Zone- the area of permeable rock or soil in which the cracks and pores
are totally filled with water.
9. Water Table- the top of the saturated zone, or depth to the groundwater under
Earth’ surface.
10. Aquifer- an underground layer of rock or sediment that holds water.
11. Artesian well- a well in which water rises because of pressure within the aquifer
Eutrophicationthe buildup over time of nutrients in freshwater
lakes and ponds that leads to an increase in
the growth of algae.
Tributary
-a stream or river that flows into a larger river.
Watershedthe land area that supplies water to a river
system.
Unsaturated Zonethe layer of rocks and soil above the water
table in which the pores contain air as well as
water.
What is a River System? Pg. 271
The streams and smaller rivers
that feed into a main river are
tributaries.
Tributaries flow toward the main
river because they are pulled by
the force of gravity.
A river and all the
streams and smaller rivers
that flow into it together
make up a river system.
Fig. 1 Surface Water and Groundwater pg. 271
River System
The lower Suwannee River flows
past Gainesville, Florida, and
empties into the Gulf of Mexico.
Circle a river system on the map
What is a River System?
The land area that supplies water
to a river system is a
watershed, or drainage basin.
One watershed is separated from
another by a ridge of land
called a divide. The streams
on each side of a divide flow in
different directions.
Pg. 272
Fig. 2 Surface Water and Groundwater pg. 272
Major Watersheds of the United
States
The land area that supplies water to a
river system is called a watershed.
•Draw the path that water would take
from the Platte River’s source to the
ocean.
•Which watersheds would the water
pass through?
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Assess your Und.
How Do Ponds and Lakes Form and Change?
Pg. 273
Ponds and lakes form
when water collects in hollows and
in low-lying areas of land.
Unlike rivers, ponds and lakes contain
still or standing water.
Sunlight reaches to the bottom of all
parts of a pond, but most lakes
have some bottom areas that are
too deep for much sunlight to
reach them.
How Do Ponds and Lakes Form and Change?
Lakes can form when a river bends as it
encounters obstacles.
A new channel forms that cuts off the bend.
The cut-off bend becomes an oxbow lake.
•
Some lakes formed from depressions
created by ice sheets that melted at the
end of the Ice Age.
• Others were created by movements of
Earth’s crust that formed long deep rift
valleys.
• Lakes can form when a volcano blocks a
river and they can form in the empty
craters of volcanoes.
Pg. 273
Apply it!! Surface Water and Groundwater
What are Ponds and Lakes?
1. Complete the Venn diagram
to compare and contrast
characteristics of lakes and
ponds.
2. Based on your answers,
write an operational
definition for lake.
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pg. 273
Lake Formation Pg. 274
In Florida, many lakes have
formed in natural depressions called
sinkholes. People can also create a
lake by building a dam. A lake that
stores water for human use is a
reservoir.
If you watch a lake or pond over
many years, you will see it change. In
time, the lake may shrink and become
shallower.
Natural processes and
human activities can cause lakes
to disappear.
Eutrophication.
Pg. 275
What can cause lakes to
disappear?
Natural processes and human activities
When lake organisms die, bacteria
break down their bodies and
release nutrients into the water.
Over time, nutrients can build up in
a lake in a process called
eutrophication.
Algae use the plentiful nutrients
and grow into a thick layer that
blocks sunlight form reaching
lake plants.
The lake plants die and the animals
that eat them die as well.
Decaying material piles up and the
lake becomes shallower and
eventually fills in.
Eutrophication Pg. 275
Human activities can cause
eutrophication. Fertilizer in
runoff from farmlands
contains nutrients that
increase eutrophication when
the runoff enters pond and
lakes.
Fig. 4 Surface Water and Groundwater pg. 275
Eutrophication
Write a caption for each
diagram to explain the
changes that occur during
eutrophication?
Assess your Und.
How Does Water Move Underwater? Pg. 276
Underground water generally comes from
precipitation, which soaks into the
ground.
Water underground trickles
down between particles of soil and
through cracks and spaces in layers
of rock.
 Because they have large and
connected pores, materials such as
sand and gravel allow water to pass
through, or permeate and are called
permeable materials.
 Other materials, such as clay have few
or no pores or cracks or the pores are
very small. These materials are less
permeable than sand. Granite is
impermeable, meaning that water
cannot pass through easily.
Water Zones pg. 277
The top layers of rock and soil
contain air as well as water and
are called the unsaturated
zone.
At some depth the water reaches
the saturated zone, a level
where the pores in the ground
are saturated with water.
The top of the saturated zone is
called the water table. The
saturated zone reaches deep
into the Earth even though the
rock becomes less permeable
the deeper you go.
Do the Math!
Fig. 6 Surface Water and Groundwater pg. 278
R. Pg 278/9
Springs and Wells
Suppose you are a farmer looking
for water sources.
Draw lines showing where you would
drill a regular well and artisian well.
Explain why you chose those
locations.
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Assess your Understanding.