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? 1. Where is the United States continental divide (the highest area which divides the U.S)? 2. 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? 1. Canyon Formation: Over thousands of years stream and river erosion can cut into the earth to form caynons. 1. 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 Crustal Movement: The Earth’s crust can move and create depressions that fill in with water Volcanic Eruption: After a volcanic eruption the top of the volcano can fill with water. - Caldera:

Continued - 4. Formation of a dam: - Human-made lake - Ex. Hoover dam 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.

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.

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  Bogs: a wetland dominated by peat moss  Marshes: a wetland dominated by grasses

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  pg pg