1. water cycle - earth’s water is recycled through two main processes: condensation and...
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Surface Water
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Surface Water Movement
Water cycle - earth’s water is recycled through two main processes: condensation and evaporation. It is also referred to as the hydrological cycle.
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Water Cycle
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Process 1) Evaporation – Changing a liquid to a gas, 2) Condensation - changes a gas to a liquid 3) Precipitation - falling of H2O from the sky as rain, sleet, snow,
hail, etc. 4) Run off - water flowing down a slope along the earth’s surface amount of run off is determined by the size of pores or spaces
where water can accumulate. Vegetation soils allow water to seep into the ground, compact soils do not. Light precipitation gives water time to seep downward, heavy precipitation does not.
Holding capacity of the soil is affected by the chemical/ physical composition of the soil.
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Soil
Humus is decayed organic matter with minerals Particle size determines the amount of water that
seeps into the ground. Humus - medium size/ Sand - large/ Clay fine
(less penetrable) Slopes allow water to move from high level to
low levels. Greater potential for erosion.
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Humus/ Clay/Sand
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Stream Systems
Stream SystemsWater other than run off, sometimes collects in channels as run off increases so does the channel. (erosion widens out) - a stream is born. Large channels create rivers fed by tributaries.
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Streamload
All the material’s that are carried with the movement of water in a channel. There are 3 ways to carry a load: 1) Solution - materials are dissolved in a stream’s water. Ex.
Calcium carbonate, limestone, and marble amounts are expressed as parts per million (ppm) Streams commonly carry magnesium compounds.
2) Suspension - particles are held up by the turbulance of the Stream 3) Bedload - sand, pebbles, and cobbles force of the water to
pull and push or roll the material along the bed of the stream
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Carrying Capacity
Ability of the stream to transport material, dependent on the velocity and amount of moving water Bed abrasion occurs when materials rub off one another - erodes the bed
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Carrying Capacity Cont…
The channels slope, depth and width affect the speed and direction in which the water moves.
Discharge - measures the volume of water that flows over a particular location within a given time period - expressed in m³/sec Formula: D = w x d x v of H2O Depth width depth volume Mississippi - average discharge 173,600 m³/sec Flood Plain - river over flow banks and water floods the land along the
river bed Amazon River - 10x the discharge as the Mississippi River - is the largest
river in the world
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Small streams - brook and creeks, Watershed - all the land area whose water drains into a stream. (drainage basin) ex. Mississippi - largest river in the U.S.
Flood Plains are the most fertile land and at times used for farming
Sediment is dropped as the floor recedes Floods are natural occurrences Upstream floods - floods of areas due to heavy
rainstorms Gauging Station and satellites monitor the flow
of water
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Major rivers of North America
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Water Shed
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Mississippi Basin Map
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Gauging Station
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Stream Development Stream Development Stream changes width, shape, and size and the landscape as it flows -
adequate supply of water is needed Headwaters - region where water accumulates to supply the stream -
commonly found in mountains Moving water carves a narrow path - stream channel Stream bank - sides of the channel
Rock and soil are eroded away called head ward erosion V-shaped channels are formed with steep sides - called gorges or canyons, ex.
Colorado River. A usable chasm - Yellowstone River. Erosion will continue until its bas level reaches sea level
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Meandering Streams
Streams that are U shaped and with little slope.
The water begins to erode the over all path is bent or curved – meander.
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Oxbow Lake
When deposition drops enough sediment, it blocks the meandering
· Forms and Oxbow Lake
Deposition · Forms deltas - ex. Mississippi deposit
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WetLands
Wetlands - land area that is covered with water for a large part of the year, ex. Bogs, marches, swamps Bogs - not stream fed, water comes from precipitation Water logged soils - peat moss (Sphagnum) Soil is very acidic due to the decay of peat moss Plant species - Venus Fly Trap, sundew Marsh grasses trap sediments - slows down water
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Lakes And Fresh waterLakes - Depression in the surface materials of the landscape that collects and holds water Some are oxbow, glacial origin (Great Lakes) Prehistoric Lake - Great Salt Lake (Utah) Cirque - carved lakes in the mountains by valley glaciers Precipitation, runoff and underground sources maintain the water supply
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Great Lakes
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Satellite Picture
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Lake Tahoe largest Alpine lake
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Yellowstone Lake-Largest High Altitude Lake
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Eutrophication
- A process of a lake becoming rich in nutrients from the surroundings,Ex. big algae bloom (pond scum - slimy substance) Over population creates a depletion of O2
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Euthrophication lake
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Euthrophication Lake in S. CA
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Wetlands
Wetlands - land area that is covered with water for a large part of the year, ex. Bogs, marches, swamps
Bogs - not stream fed, water comes from precipitation Water logged soils - peat moss (Sphagnum) Soil is very acidic due to the decay of peat moss Plant species - Venus Fly Trap, sundew Marsh grasses trap sediments - slows down water
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Moraine dammed lakesglacier gauged out of the land during the ice age.
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Glacial Moraines
Glacial moraines originally dammed some of these depressions and restricted the outward flow of water.
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Kettle Lakes
Kettle lakes - formed as blocks of ice left on the outwash plainahead of melting glaciers eventually melted and left depressions called kettles. When these depressions filled with water,they formed kettle lakes.
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Kettle Lake
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Glacial action