Transcript Surface Water PowerPoint

Mississippi River Basin
NC River Basins Map
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Water Resources
Aquifer Depletion
NOAA: Water Cycle
Water Cycle
The Water Cycle
Freshwater
Sections 9.2 & 9.3
Stream Development,
Lakes, Wetlands
Headwaters: Region where water
first accumulates to supply a stream.
Common to be high in the mountains
where falling precipitation accumulates in
small gullies and forms briskly moving
streams
Stream
Headwaters
Tundra Lake headwaters of Stein River Lytton, 1983 August 07 (British Columbia, Canada)
people.uleth.ca/~holzmann/photos/index.html
Stream
Headwaters
http://www.2steger.de/canada/40_Stein_Valley_Traverse.htm
Stream Channel: Narrow pathway
carved into sediment or rock by the
movement of surface water.
Stream Bank: Ground bordering
each side of a stream that keeps the
moving water confined
Stream
Stream
Banks
Banks
Stream
Channel
http://www.littleriverbigfuture.org/images/In%20txt%20pics/Stream_erosion_1.jpg
Immature River: Young river erodes
path through sediment or rock forming a
V-shaped channel.
V-shaped channels have steep sides and
sometimes form canyons or gorges.
Inner gorge of the Grand Canyon, located in northwestern Arizona. Carved by the power of the Colorado River, the canyon stretches for
277 miles. http://www.scienceclarified.com/landforms/Basins-to-Dunes/Canyon.html
Mature River: As the river becomes
more mature, the V-shaped valley will be
eroded away forming a broader, wider
river.
This bridge across the Danube River links Hungary with Slovakia
http://en.wikipedia.org/wiki/Image:MariaValeriaBridge.jpg
Meander: A bend or curve in a stream
channel caused by moving water
Meanders of the Rio Cauto at , Cuba.
http://en.wikipedia.org/wiki/Image:Rio-cauto-cuba.JPG
•Water in the straight parts of a stream flows at
different velocities depending on the location of
the water in the channel.
•Generally, water in the
center is flowing faster at
the maximum velocity while
water along the bottom and
sides flows more slowly
because it experiences
friction as it moves against
the land.
• The water moving along the outside of a meander
curve experiences the greatest rate of flow within the
meander.
• The water that flows along
this outside part of the
curve continues to erode
away the sides of the
streambed, thus making
the meander larger.
• Along the inside of the
meander, the water moves
more slowly and deposition
is dominant.
Oxbow Lake: A lake formed
from a cut-off meander
•After some degree of
winding it is common for a
stream to cut off a meander
and once again flow along a
straighter path.
•The stream then deposits
material along the adjoining
meander and eventually
blocks off its water supply.
•The blocked-off meander
becomes and oxbow lake,
which eventually dries up.
http://homepage.ntlworld.com/harry.wickens/borneo/borneo070.jpg
http://www.gly.uga.edu/railsback/1121RiverOxBow.jpeg
Alluvial Fan: Sloping depositional features
formed at the bases of slopes and composed
mostly of sand and gravel.
•Streams that lose velocity also lose their ability to carry
sediment.
•In dry regions mountain streams commonly flow down
narrow valleys onto broad, flat, valley floors. As a stream
flows from the mountain to the flat valley, the stream’s
gradient** may suddenly decrease causing the stream to
drop its sediment as a fan-shaped deposit.
•**A stream’s gradient is the difference in elevation between two
points on the stream divided by the distance along the stream
(Essentially the slope of the stream)
http://www.tulane.edu/~sanelson/images/allfan.gif
http://en.wikipedia.org/wiki/Image:Alluvial_fan_01.JPG
Delta: When a stream enters a large body of
water (example: an ocean), the stream looses
its velocity and the stream’s load is deposited in
a triangular shape.
•Usually silt and clay particles
•As a delta develops, sediments build up and slow
the stream water, sometimes even blocking its
movement.
•Smaller distributary streams then form to carry the
stream water through the developing delta.
http://www.sln.org.uk/geography/schools/blythebridge/delta.jpg
http://earth.usc.edu/~slund/systems/topic7pics/image9.gif
http://serc.carleton.edu/images/research_educati
on/katrina/map_of_delta.v2.gif
http://earthobservatory.nasa.gov/IOTD/view.php?id=2521
Lake: A depression in the surface materials of
a landscape that collects and holds water
•Lakes accumulate water from streams, runoff,
precipitation, and springs.
Reservoir: A man-made structure used for
storing water for later use.
1st A sturdy dam is built.
2nd A stream is allowed to flow behind the dam
and will eventually fill the area with water.
Falls Lake; www.saw.usace.army.mil/falls/index.htm
Wetland: A land area that is covered with
water for a large part of the year.
•Include bogs,
marshes, and swamps
•Serve as a filtering
system and improve
water quality
•Provide vital habitats
for and abundance of
wildlife.
http://www.iwla.org/index.php?id=416
http://i197.photobucket.com/albums/aa19/forjerz/Sunday-080.jpg
http://dcm2.enr.state.nc.us/ncwp/aerial.jpg
http://h2o.enr.state.nc.us/ncwetlands/gbheron.JPG
http://h2o.enr.state.nc.us/ncwetlands/swsms.html
Estuary: Where the lower end
of a freshwater river or stream
enters the ocean
•The water in estuaries is a mix of freshwater and salt
water called brackish.
•Estuaries are nurseries to the young of many different
species including ocean fish species.
•Some large estuaries include the Chesapeake
Bay in Maryland/Virginia and the Pamlico Sound
in North Carolina.
Groundwater