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The Structure of Hydrosphere. The Structure of Hydrosphere. Oceans—96.5% of water found here Fresh water—3.5% of water found here. Fresh water distribution: Ice: 1.762% Groundwater: 1.7% Surface Fresh Water: 0.014% Atmosphere and soil: 0.002%.
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The Structure of Hydrosphere • Oceans—96.5% of water found here • Fresh water—3.5% of water found here • Fresh water distribution: • Ice: 1.762% • Groundwater: 1.7% • Surface Fresh Water: 0.014% • Atmosphere and soil: 0.002%
Understanding Where Your Water Is Located—Oceans and Ice • What bodies of water hold the largest amount of water? • Oceans—the largest bodies of water on Earth (contain salt water only) • What features house water as ice? • Icebergs: a large piece of freshwater ice floating in open waters • Glaciers: any large mass of ice that moves slowly over land • *permanent snow areas also “house” water as ice
Fresh Water Locations—Surface Water • What is the difference between a watershed and a river basin? • Both terms describe land that drains into a river, stream or lake River Basin: the term used to describe an area that drains into a large river. Watershed: the term used to describe an area that drains into a smaller river or stream.
What do the U.S river basins look like? • Where is the United States continental divide (the highest area which divides the U.S)? • Which river basin supplies the water for the local rivers in southeast North Caroline?
Fresh Water Locations—River Basins and Watersheds • Larger river basins are made up of many interconnected watersheds • Example: Cape Fear and Neuse River Basins are made of many small watersheds • The water in a watershed runs to the lowest point—a river, stream, lake, or ocean
Fresh Water Locations—Rivers, Streams, and Lakes • What is a river? • A large channel along which water is continually flowing down a slope—made of many streams that come together • What is a stream? • A small channel along which water is continually flowing down a slope—made of small gullies • What is a lake? • A body of water of considerable size contained on a body of land
What are the two types of streams? Meandering Stream: Streams that have channels with many curves. Braided Stream: Streams with many bars and islands separated by channels. Activity: To the best of your ability; draw a meandering and braided stream in your notes. (I will demonstrate on the board)
What are the parts to a stream? Turn to Pg.165 in the textbook: Meander: The turn in a meandering stream. - Outside of a meander moves faster than the inside. - Sediment deposits on the inside- Sediment erodes on the outside Point Bar: Develops on the inside where sediment deposits. Cutoff Meander: A meander that had broken off from the stream.
What is stream erosion? Stream erosion: The movement of rock and sediment to other places through the flow of a stream. - Bed Load: Bottom- Sand and Gravel. - Suspended Load: Middle- Silt and Clay - Dissolved Load: Top- Dissolved Minerals
What is the result of stream erosion? • Canyon Formation: Over thousands of years stream and river erosion can cut into the earth to form caynons. • Ex. Colorado river and the Grand Canyon.
Continued 2. Alluvial Fans: Streams deposit sediment onto a flat area of land.
Continued 3. Delta: Streams deposit sediment into a body of water.
Engage Question: Lakes • Recall a time that you visited a lake or seen a lake on television. • 1. Describe the plants and animals that you saw around this area. • 2. How is a lake different from a river or stream?
How do lakes form? • 1. Glaciers: Glaciers scoured out depressions that over time fill in with runoff water. • Natural Lakes: • Ex. Great Lakes- They hold 18 percent of Earth’s freshwater. • http://upload.wikimedia.org/wikipedia/commons/c/c3/Great_Lakes_from_space.jpg • 2. Crustal Movement: The Earth’s crust can move and create depressions that fill in with water. • 3. Volcanic Eruption: After a volcanic eruption the top of the volcano can fill with water. • Caldera: http://www.gvb-csic.es/CCDB/iamgenes/KatmaiCaldera.jpg
Continued • 4. Formation of a dam: • Human-made lake • Ex. Hoover dam • http://philip.greenspun.com/images/pcd2882/hoover-dam-aerial-91.4.jpg Thought Question: Why might a dam and reservoir be useful in a dry area? Answer: The reservoir could store water for drinking and irrigation.
What is found in lakes? • Plant Life: Plant life near a lake is usually found near the shallow parts. Why? • Because, plants need sunlight to live and produce. • Amphibians: Organisms that use both the land and the water. • Ex. Frogs, Ducks, Turtles, etc. • Fish • Plankton: small organisms found near the surface of the water. • Sediment and Nutrients: • Nutrients: Compounds such as nitrates and phosphates that are used by plants and algae to grow. • Sediment: Can a lake be the same depth forever? • No, sediment will build and over time the lake will decrease in depth. Eventually becoming dry. http://techalive.mtu.edu/meec/module08/FoodWeb.htm
What is eutrophication? Eutrophication: An increase in nutrients and organism that is a normal part of a lake’s life. Thought Question: How could building a dam lead to an increase in eutrophication in a lake? Answer: When a dam is constructed and forms a reservoir, sediment can collect behind the dam and quickly fill in the reservoir.
How does a lake turnover?Pg. 176 Textbook • Turnover-The mixing of lake water, which causes nutrients from deep in the lake to move to the surface. • Summer Lake: • Nutrients are concentrated on the bottom with the more dense colder water. • Low nutrient count on top with the less dense water . • There is a separation of nutrients due to water density. • Autumn Lake: • The top layer of water becomes colder and more dense. • The top layer sinks and mixes with the nutrient rich water from the bottom. • Turnover causes nutrients from deep in the lake to move upward toward the surface. • http://www.islandnet.com/~see/weather/graphics/photos0506/laketurnover.gif
Other Surface Waters • What is a wetland? • An area where the water table is at, near or above the land surface long enough during the year to support adapted plant growth • What are the types of wetlands? • Swamps, bogs, and marshes • Swamp: a wetland dominated by trees • http://dnr.state.il.us/wetlands/images/swamp21.jpg • Bogs: a wetland dominated by peat moss • http://www.travelblog.org/Photos/223909 • Marshes: a wetland dominated by grasses • http://water.epa.gov/type/wetlands/images/marsh.jpg
What types of animals depend on wetlands? • Wetlands provide habitats for both water and land animals. • Migrating birds: • Provide cover and resting areas during long flights. • Mink and Muskrat • Reptiles
Why are wetland important? • They trap sediment: • The trapped sediment cannot enter into lakes and streams. This keeps streams and lakes clear. • They use a lot of excess nutrients: • Wetlands near lakes and streams use these nutrients for their plant growth. Decreasing eutrophication.
Fresh Water Locations--Groundwater • What is groundwater? • The water found in cracks and pores in sand, gravel and rocks below the earth’s surface • What is an aquifer? • A porous rock layer underground that is a reservoir for water • http://geoscape.nrcan.gc.ca/ottawa/images/biggroundwater.jpg