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Do Now Sit SILENTLY and answer the following in your notes. You do not have to copy the questions, though I am confident some of you will still ask…le sigh What are the 2 atoms that make up a water molecule? Balance the following… –___H 2 + ____O 2 ____H 2 O If water changes from a solid to a liquid to a gas then it is undergoing what kind of change? How do you know? What are some ways that we as humans pollute water systems?
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What makes water so special?
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Water three A water molecule (H 2 O), is made up of three atoms --- one oxygen and two hydrogen. H H O
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Special Properties Water is the only substance on Earth that occurs naturally as a solid, a liquid, and a gas. It is often referred to as ‘the universal solvent’ because so many other substances dissolve in it. This characteristic is one reason that the water encountered on Earth is rarely pure.
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So…what makes water so special?
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Water is Polar!!!! oxygennegative The oxygen end “acts” negative hydrogenpositive The hydrogen end “acts” positive POLAR, like a magnet. Causes the water to be POLAR, like a magnet.
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Hydrogen Bonds Exist Between Water Molecules Formed between a highly Electronegative atom (like oxygen in another water) of a polar molecule and a hydrogen Formed between a highly Electronegative atom (like oxygen in another water) of a polar molecule and a hydrogen Weak bond, but strong in great numbers Weak bond, but strong in great numbers
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Interaction Between Water Molecules Negative Oxygen end of one water molecule is attracted to the Positive Hydrogen end of another water molecule to form a HYDROGEN BOND
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What are the Properties of Water?
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Properties of Water Cohesion Cohesion
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Properties of Water Cohesion Cohesion Adhesion Adhesion
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Properties of Water Cohesion Cohesion Adhesion Adhesion High Specific Heat High Specific Heat
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Properties of Water Cohesion Cohesion Adhesion Adhesion High Specific Heat High Specific Heat High Heat of Vaporization High Heat of Vaporization
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Properties of Water Cohesion Cohesion Adhesion Adhesion High Specific Heat High Specific Heat High Heat of Vaporization High Heat of Vaporization Less Dense as a Solid Less Dense as a Solid
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Cohesion Attraction between particles of the same substance (why water is attracted to itself) Attraction between particles of the same substance ( why water is attracted to itself) Results in surface tension (a measure of the strength of water’s surface) Results in surface tension (a measure of the strength of water’s surface)
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Cohesion … Helps insects walk across water, but how is it helpful to people?
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Adhesion Attraction between two different substances. Attraction between two different substances. Water will make hydrogen bonds with other surfaces such as glass, soil, plant tissues, and cotton. Water will make hydrogen bonds with other surfaces such as glass, soil, plant tissues, and cotton. Capillary action-water molecules will “tow” each other along when in a thin glass tube. Capillary action-water molecules will “tow” each other along when in a thin glass tube.
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Adhesion Causes Capillary Action Which gives water the ability to “climb” structures
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High Specific Heat Amount of heat needed to raise or lower 1g of a substance 1° C. Amount of heat needed to raise or lower 1g of a substance 1° C. Water resists temperature change, both for heating and cooling. Water resists temperature change, both for heating and cooling. – Would you rather walk on sand or in water on a beach on a hot summer day? – Which would be warmer that night? Why?
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High Heat of Vaporization
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Water vapor Water vapor forms a kind of global ‘‘blanket” which helps to keep the Earth warm. Heat radiated from the sun Heat radiated from the sun warmed surface of the earth is absorbed and held by the vapor by the vapor.
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Water is Less Dense as a Solid Which is ice and which is water? Which is ice and which is water?
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Exit Ticket 1.Draw a water molecule with labeled atoms and charges. 2.What is the property called that describes water sticking to itself? 3.Is ice les dense or more dense than liquid water? How do you know?
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Do Now Why is water’s property of high heat of vaporization important to the earth and more specifically to us? What 2 properties of water are important for plants specifically and why? Explain why solid water (ice) is able to float on liquid water.
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Water Distribution Water covers approximately 71% of the Earth’s surface (USGS). Most of this water (97%) is not drinkable because it is saltwater.
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Water Distribution The majority of freshwater (3%) exists in ice caps, glaciers, and oceans. 77% of the freshwater is frozen. Of the 23% that is not frozen, approximately a half of a percent is available to supply living organisms with what they need to survive. The availability of water varies with local geography and allows humans to utilize water as a resource.
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Salinity Salinity = total amount of solid material dissolved in water Can be determined by measuring water conductivity Typically expressed in parts per thousand (‰) Figure 5-15
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So why is the Ocean so Salty?! Dissolved chemicals eroded from the Earth's crust and washed into the sea. Solid and gaseous ejections from volcanoes, suspended particles swept to the ocean from the land by onshore winds, and materials dissolved from sediments deposited on the ocean floor have also contributed.
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Salinity Cont. Salinity in ocean waters is increased by evaporation or by freezing of sea ice and it is decreased as a result of rainfall, runoff, or the melting of ice. The average salinity of seawater is 35 parts per thousand(3.5%). Salinities are much less than average in coastal waters, in the polar seas, and near the mouths of large rivers. In recent years, salinity has been changing across the world’s oceans. Why do you think that is?
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Processes affecting seawater salinity Processes that decrease seawater salinity: –Precipitation –Runoff –Icebergs melting –Sea ice melting Processes that increase seawater salinity: –Sea ice forming –Evaporation –Hydrothermal vents
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What are Hydrothermal Vents?
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Hydrothermal Vent Hydrothermal vent- a deep-sea hot spring where heated seawater forces its way up through the crust. Discovered rich communities in 1977. Temperatures range from 10-20⁰C (50-68⁰F) to 350⁰C (660⁰F). Mineral particles such as sulfides and carbonates precipitate to form chimneys. Chemosynthetic microbes form basis of food chain
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Mid-Ocean Ridge
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Hydrothermal Vents
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Where are vents located? Where magma is close to the surface – Mid Ocean Ridges.
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Mid-Ocean Ridges http://www.divediscover.whoi.edu/ridge/axial.html
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1977 1 st vent found by Alvin
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Alvin?
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Alvin http://www.youtube.com/watch?v=XotF9fzo4Vo
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Submersibles, ROVs, & AUVs
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http://www.divediscover.whoi.edu/vents/vent-infomod.html STEP 1 Cold water (2 o C) seeps through cracks and is heated up (up to 400 o C) How are vents created?
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STEP 2 Water heated to 350-400 o C – high temps. facilitate leaching of minerals from rock. Oxygen is removed chemically Picks up dissolved metals (Fe, Cu, Zn). H20 picks up Hydrogen sulfide.
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STEP 3 Hot liquid under pressure finds an exit. Dissolved metals and H2S are carried up and out. Effluent is acidic and toxic to most animals.
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White and Black Smokers
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Black Smoker Hottest of all vents
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monosulfide. This compound gives the smoker its black color. They spew mostly iron and sulfide, which combine to form iron monosulfide. This compound gives the smoker its black color.
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WHITE SMOKERS White smoke contains silica Anhydrite is created (white mineral) Contains compounds of barium, calcium, and silicon Still hot enough to cook pasta – but not as hot as black smokers
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Vent crabs
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Zooarcid Fish (Eelpout)
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Giant Vent Mussel
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Lepetodrilus- limpets
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Pompeii Worm
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Giant Hydrothermal Vent Clam
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Anemones
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Constituents of ocean salinity Average seawater salinity = 35‰ (3.5%) Main constituents of ocean salinity: –Chloride (Cl – ) –Sodium (Na + ) –Sulfate (SO 4 2– ) –Magnesium (Mg 2+ ) Figure 5-13
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Salinity variations Location/typeSalinity Normal open ocean33-38‰ Baltic Sea10‰ (brackish) Red Sea42‰ (hypersaline) Great Salt Lake280‰ Dead Sea330‰ Tap water0.8‰ or less Premium bottled water0.3‰
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Seawater desalination Desalination methods: –Distillation Solar Heat –Electrolysis –Reverse osmosis –Freeze separation Figure 5-25 Distillation Reverse Osmosis Figure 5-26
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But why do we really care about salinity anyway? The ocean currents are affected by salinity and ocean currents regulate climate around the world. The earths oceans and seas are also the biggest recyclers of gasses in the atmosphere. Finally the oceans store heat that allows us to have the seasons.
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What are Currents? Currents are the slow movement of sea water by different factors –Surface currents are caused by wind and temperature variations –Deeper currents are caused by changes in density (salinity) and temperature –http://www.youtube.com/watch?v=qeZgJzt3m0 4
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Heat Transport by Currents Surface currents play significant roles in transport heat energy from equatorial waters towards the poles May serve as “heat sources” to cooler overlying air, “heat sinks” from warmer Evaporation and condensation participate in latent heat exchanges
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Matter Transport and Surface Currents Currents also involved with gas exchanges, especially O 2 and CO 2 Nutrient exchanges important within surface waters (including outflow from continents) and deeper waters (upwelling and downwelling) Pollution dispersal Impact on fisheries and other resources
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The currents move in a circular motion
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Deep current and Surface current interaction
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What happens to the regular cycle when salinity is disrupted? The normal circular motion gets bent and skewed a bit.
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Do Now Sit SILENTLY and answer the following questions in your notes. What are the 4 main properties of water? Give a definition in your own words describing each of the properties listed in the previous question. Explain why England has a similar climate to ours despite being so much farther north.
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Gyres - large circular-moving loops of water Five main gyres (one in each ocean basin): North Pacific South Pacific North Atlantic South Atlantic Indian Generally 4 currents in each gyre Centered about 30 o north or south latitude Current Gyres
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“Great Pacific Garbage Patch” Estimate: 46,000 pieces of floating garbage/mi 2. North Pacific Subtropical Gyre
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Stop and Check Why does trash collect in the center of gyres? Infer why you think that the pacific gyre has a particularly large amount of garbage.
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North Pacific Subtropical Gyre 135° to 155°W and 35° to 42°N
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North Pacific Subtropical Gyre http://marinedebris.noaa.gov/info/patch.html#6 Great Pacific Garbage Patch- Good Morning America 2010 http://www.youtube.com/watch?v=Co43TXJXryI
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Lost at Sea
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January 1992 - shipwrecked in the Pacific Ocean, off the coast of China November 1992 - half had drifted north to the Bering Sea and Alaska; the other half went south to Indonesia and Australia 1995 to 2000 - spent five years in the Arctic ice floes, slowly working their way through the glaciers 2001 - the duckies bobbed over the place where the Titanic had sunk 2003 - they were predicted to begin washing up onshore in New England, but only one was spotted in Maine 2007 - a couple duckies and frogs were found on the beaches of Scotland and southwest England. Duckie Progress
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Upwelling in the World Ocean http://www.youtube.com/watch?v=Al8WrXkLuL4
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Upwelling Upwelling is the process that brings cold nutrient rich water to the surface. It comes to the surface, because winds move water away forcing the water below it to move up, much like the process of convection.
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Stop and check Why does water move from the bottom to the surface?
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Upwelling refers to deep water that is brought to the surface. Areas of upwelling are created by surface winds that pull water away from an area. This deficit of water on the surface invites water to come up from deeper regions.
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Types of Upwelling Equatorial Coastal Seasonal
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The Monsoonal wind shifts in Oman create very different conditions. August, 1999 Offshore winds: Upwelling April, 1999 Onshore winds: Downwelling Wind
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The deep water that surfaces in upwelling is cold; by looking at Sea Surface Temperature maps we can identify cool upwelled water versus hotter surface water.
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http://www.youtube.com/watch?v=H7sACT0Dx0Q Upwelled water also contains nutrients (nitrate, phosphate, silicate) and dissolved gases (oxygen and carbon dioxide) that are not utilized at depth because of a lack of sunlight. Now on the surface, these nutrients and gases help to fuel photosynthesis by small algae called phytoplankton.
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Stop and check Determine why there are more nutrients in the colder darker water than in the warm surface water. Discuss with your table partner and prepare to share.
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Phytoplankton photosynthesize using specialized color pigments called chlorophyll. Thus, “ Ocean Color ” maps are another way to identify areas of upwelling. Where on this ocean color map are high phytoplankton concentrations?
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Ecological and Economic effects of upwelling: Upwelling leads to more phytoplankton More phytoplankton leads to more fish More fish lead to commercial fishing jobs and to more seafood
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Stop and check Why is upwelling important to the ocean and us?
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Phytoplankton come in many shapes and forms. Collectively they form the base of oceanic food webs. Without upwelling many of the world’s fisheries would not thrive.
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Even though upwelling areas account for only 1% of the ocean surface, they support 50% of the worlds fisheries.
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Productivity (phytoplankton growth) of an area is determined by the rate and the duration of upwelling. Rate of upwelling determines phytoplankton cell size. Duration of upwelling determines the total amount of phytoplankton. few vs. many small vs. large
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Classification of upwelling systems in terms of rate and duration: After Thurman, H.V. (1994) Low Medium High RATE DURATION Long Short
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Moderate rates of upwelling for long duration (8 months or longer) provide the ultimate combination for a large fishery. With too low or too high a rate, phytoplankton are small, so there is a trophic level between the algae and the fish….therefore the fish receive less energy.
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The Water Cycle By Mr. Miller
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Water never leaves the Earth. It is constantly being cycled through the atmosphere, ocean, and land. This process, known as the water cycle, is driven by energy from the sun. The water cycle is crucial to the existence of life on our planet.
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Consider the following… Watch the following clip and while its playing define the following in your notes Evaporation Condensation Precipitation Transpiration Evection Runoff http://www.youtube.com/watch?v=i3NeMVBcXXU
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The Water Cycle
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During part of the water cycle, the sun heats up liquid water and changes it to a gas by the process of evaporation. Water that evaporates from Earth ’ s oceans, lakes, rivers, and moist soil rises up into the atmosphere.
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The process of evaporation from plants is called transpiration. (In other words, it’s like plants sweating.)
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As water (in the form of gas) rises higher in the atmosphere, it starts to cool and become a liquid again. This process is called condensation. When a large amount of water vapor condenses, it results in the formation of clouds.
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When the water in the clouds gets too heavy, the water falls back to the earth. This is called precipitation.
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When rain falls on the land, some of the water is absorbed into the ground forming pockets of water called groundwater. Most groundwater eventually returns to the ocean. Other precipitation runs directly into streams or rivers. Water that collects in rivers, streams, and oceans is called runoff.
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Eutrophication The process by which a body of water acquires a high concentration of nutrients, especially phosphates and nitrates.nutrients These typically promote excessive growth of algae. As the algae die and decompose, high levels of organic matter and the decomposing organisms deplete the water of available oxygen, causing the death of other organisms, such as fish. Eutrophication is a natural, slow-aging process for a water body, but human activity greatly speeds up the process
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Do Now Sit SILENTLY and answer the following questions in your notes. Define eutropihcation, how it is caused and whether it is good or bad for the ecosystem it is in. What is transpiration? List the steps of the water cycle and describe each.
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What is an estuary? Partially enclosed body of water Salt water estuaries –Saltwater from the ocean mixes with fresh water Fresh water estuaries –Lake water mixes with stream/river water –Freshwater the concentration of salts, or salinity, is nearly zero
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Commercial Economic Benefits Fancy steamed shrimp or fried catfish for dinner? Estuaries provide habitat for over 75% of the U.S. commercial sea catch. Estuaries support jobs and income for many Americans each year. Many estuaries are important centers of transportation and international commerce.
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Why are estuaries Important? Ecosystem Services –Water filtration –Habitat protection Ecosystem services are difficult to put a value on; they are essentially priceless.
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What Role do Estuaries Play in Earth’s Cycle? Nutrient Cycle –Elements are recycled and made available to living organisms. Water Cycle –Evaporation occurs, and also serve to recharge groundwater. Cycle of Life –Estuaries provide shelter, food and nursery grounds for animals.
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Stormwater Runoff and Water Quality
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Stormwater Runoff GDefinition: Rainfall that, instead of soaking into the ground, flows into water bodies picking up pollutants along the way http://www.kytc.state.ky.us/EnvAnalysis/Stormwaterquality/Gen_info_edu.htm
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How does runoff become groundwater? As long as water is able to run through permeable rock, it can be stored naturally as ground water. How do you think humans prevent this?
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River Basin GDefinition: defined area where all water within the area flows into a common water body GThere are 17 different river basins in NC GYou live in the Catawba River Basin, which has the largest number of people so what implications do you think there are for the environment here?
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NC River Basins http://www.cgia.state.nc.us/Portals/0/images/examples/nc_rivbasins.jpg
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Pollution GAs stormwater flows across streets and lawns, it picks up chemical pollutants GAll pollution in a river basin accumulates in the common water body
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Types of Pollution Point Source Pollution GDefinition-localized source of pollution, usually industrial and coming from a pipe GExamples GIndustry Nonpoint Source Pollution Definition- general and indirect water pollution from many diffuse sources GExamples GAgricultural Runoff GAnimal Waste GResidential Property Runoff GParking Lot and Road Runoff http://www.liverpool.nsw.gov.au/LCC/INTERNET/me.get?site.sectionshow&PAGE1230&BODY
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What’s wrong with this picture? http://www.ncstormwater.org/pages/workbook_pollution_solutions.html
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Visual Indicators of Water Quality GDiverse Organisms GBugs as Indicators of Water Quality Mayflies and Caddisflies cannot tolerate water pollution, therefore their presence in a water body indicates good water quality. Mayfly larvae http://swittersb.files.wordpress.com/2008/08/mayfly20nymph.jpg Caddisfly larvae http://www-staff.lboro.ac.uk/~gymfj2/Caddisfly.htm
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Measuring Water Quality GDissolved Oxygen GWater Temperature GpH GExtremely high or low levels of any of these indicate poor water quality A YSI Meter is used to measure these quantities.
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How do we cleanse our waters?! GRiparian buffers GA vegetated area near a stream, usually forested which helps shade and partially protect a stream from the impact of adjacent land uses such as farming GWetlands GAreas that stay saturated and support vegetation that helps control water and pollution from urban centers
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