PowerPoint Presentation

Aquatic BiodiversityChapter 8Red Tide1Core Case Study: Why Should We Care about Coral Reefs?BiodiversityFormation coral polyps + algaeImportant ecological and economic servicesModerate atmospheric temperaturesAct as natural barriers protecting coasts from erosionProvide habitatsSupport fishing and tourism businessesProvide jobs and building materialsStudied and enjoyed2Core Case Study: Why Should We Care about Coral Reefs?Degradation and declineCoastal developmentPollutionOverfishingWarmer ocean temperatures leading to coral bleachingIncreasing ocean acidity

38-1 What Is the General Nature of Aquatic Systems? Concept 8-1A Saltwater and freshwater aquatic life zones cover almost three-fourths of the earths surface with oceans dominating the planet. Concept 8-1B The key factors determining biodiversity in aquatic systems are temperature, dissolved oxygen content, availability of food and availability of light and nutrients necessary for photosynthesis. 4

Most of the Earth Is Covered with Water (~70%)Saltwater: global ocean divided into 4 areasAtlanticPacificArcticIndian Freshwater

5Most of the Earth Is Covered with Water Aquatic life zonesSaltwater: marine Oceans and estuariesCoastlands and shorelinesCoral reefsMangrove forests (see Mangrove Adventure video in Ch. 9-11 folder)FreshwaterLakesRivers and streamsInland wetlands

6The Ocean Planet

7Distribution of the Worlds Major Saltwater and Freshwater Sources

8Most Aquatic Species Live in Top, Middle, or Bottom Layers of Water PlanktonPhytoplanktonPhyto: plant, plankton: diftingPrimary producersZooplankton zoo: animalUltraplankton photosynthetic bacteria70% of primary productivity near ocean surfaceNekton strong swimmersBenthos bottom dwellersDecomposers

9Most Aquatic Species Live in Top, Middle, or Bottom Layers of Water Key factors in the distribution of organismsTemperatureDissolved oxygen contentAvailability of foodAvailability of light and nutrients needed for photosynthesis in the euphotic, or photic, zone Light can be reduced by turbidity cloudiness caused by algal blooms or sediment

10Testing turbidity

8-2 Why Are Marine Aquatic Systems Important? Concept 8-2 Saltwater ecosystems are irreplaceable reservoirs of biodiversity and provide major ecological and economic services. 12Oceans Provide Important Ecological and Economic ResourcesReservoirs of diversity in three major life zonesCoastal zone 10% of ocean, 90% of marine species!Usually high NPP due to ample sunlight and nutrientsOpen sea nutrients in short supplyEuphotic zone: 40% of the worlds photosynthesis! Ocean bottom

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Fig. 8-4, p. 165Marine EcosystemsEconomic ServicesClimate moderationFoodCO2 absorptionAnimal and pet feedNutrient cyclingPharmaceuticalsHarbors and transportation routesWaste treatmentReduced storm impact (mangroves, barrier islands, coastal wetlands)Coastal habitats for humansRecreationHabitats and nursery areasEmploymentGenetic resources and biodiversityOil and natural gasMineralsScientific informationBuilding materialsEcological ServicesNATURAL CAPITALFigure 8.4Major ecological and economic services provided by marine systems (Concept 8-2). Question: Which two ecological services and which two economic services do you think are the most important? Why?Natural Capital: Major Life Zones and Vertical Zones in an Ocean

15Estuaries and Coastal Wetlands Are Highly ProductiveEstuaries and coastal wetlands - high nutrient input from rivers River mouthsInletsBaysSoundsSalt marshesMangrove forests

Seagrass BedsSupport a variety of marine speciesStabilize shorelinesReduce wave impact16Estuaries and Coastal Wetlands Are Highly ProductiveImportant ecological and economic servicesCoastal aquatic systems maintain water quality by filteringToxic pollutantsExcess plant nutrientsSedimentsAbsorb other pollutants Provide food, timber, fuelwood, and habitatsReduce storm damage and coast erosion17View of an Estuary from Space

18Components and Interactions in a Salt Marsh Ecosystem in a Temperate Area

19Rocky and Sandy Shores Host Different Types of OrganismsIntertidal zone tides rise and fall every 6 hoursRocky shoresSandy shores: barrier beachesOrganism adaptations necessary to deal with daily salinity and moisture changes hold onto something, protective shell, dig into mudImportance of sand dunes plant roots hold sand in place. They protect inland areas from the sea.20

Beach fleaPeanut wormTiger beetleBarrier BeachBlue crabClamDwarf oliveHigh tideSandpiperGhost shrimpSilversidesLow tideMole shrimpWhite sand macomaSand dollarMoon snailFig. 8-9, p. 169

Rocky Shore BeachSea starHermit crabShore crabHigh tidePeriwinkleSea urchinAnemoneMusselLow tideSculpinBarnaclesKelpSea lettuceMonterey flatwormNudibranchStepped ArtLiving between the TidesFigure 8.9Living between the tides. Some organisms with specialized niches found in various zones on rocky shore beaches (top) and barrier or sandy beaches (bottom). Organisms are not drawn to scale.Primary and Secondary Dunes

22Coral Reefs Are Amazing Centers of BiodiversityMarine equivalent of tropical rain forestsHabitats for one-fourth of all marine species23Natural Capital: Components and Interactions in a Coral Reef Ecosystem

24The Open Sea and Ocean Floor Host a Variety of SpeciesVertical zones of the open seaEuphotic zone Eu:good, phot: lightBathyal zone - dim lightAbyssal zone: receives marine snowDeposit feeders eat mud (worms)Filter feeders - filter water (shellfish, sponges)Upwellings bring nutrients up from bottom, caused by winds and ocean currentsPrimary productivity and NPP low per unit area, but since area is so large, large overall25

Hadal (like Hades) deep sea trenchesAbyssal sea floorLittoral between high and low water mark in rivers, lakes, seasAnd areas near shorelineshttp://www.youtube.com/watch?v=8101vCjM7nY http://www.youtube.com/watch?v=c-cYksk1Z70 8-3 How Have Human Activities Affected Marine Ecosystems? Concept 8-3 Human activities threaten aquatic biodiversity and disrupt ecological and economic services provided by saltwater systems. 28Human Activities Are Disrupting and Degrading Marine SystemsMajor threats to marine systems Coastal developmentOverfishingRunoff of nonpoint source pollutionPoint source pollution Habitat destructionIntroduction of invasive speciesClimate change from human activitiesPollution of coastal wetlands and estuaries

29Case Study: The Chesapeake Bayan Estuary in TroubleLargest estuary in the US; polluted since 1960Population increasedPoint and nonpoint sources raised pollutionPhosphate and nitrate levels too highOverfishing1983: Chesapeake Bay ProgramUpdate on recovery of the BayShould we introduce an Asian oyster?Pros:Cons:30

Chesapeake Bay31http://www.cdph.ca.gov/pages/musselquarantinefaq.aspx https://www.flickr.com/photos/122341073@N07/14596266933/

8-4 Why Are Freshwater Ecosystems Important?Concept 8-4 Freshwater ecosystems provide major ecological and economic services and are irreplaceable reservoirs of biodiversity. 33Water Stands in Some Freshwater Systems and Flows in OthersStanding (lentic) bodies of freshwaterLakesPondsInland wetlandsFlowing (lotic) systems of freshwaterStreamsRivers

34Water Stands in Some Freshwater Systems and Flows in OthersFormation of lakesGlaciationCrustal displacementVolcanic activityFour zones based on depth and distance from shoreLittoral zone near shoreLimnetic zone open water, top layerProfundal zone too dark for photosynthesisBenthic zone bottom, decomposers and detritivores live here

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Fig. 8-14, p. 174NATURAL CAPITALFreshwater SystemsEcological ServicesEconomic ServicesClimate moderationFoodNutrient cyclingDrinking waterWaste treatmentIrrigation waterFlood controlHydroelectricityGroundwater rechargeHabitats for many speciesTransportation corridorsGenetic resources and biodiversityRecreationScientific informationEmploymentFigure 8.14Major ecological and economic services provided by freshwater systems (Concept 8-4). Question: Which two ecological services and which two economic services do you think are the most important? Why?Distinct Zones of Life in a Fairly Deep Temperate Zone Lake

37Some Lakes Have More Nutrients Than OthersOligotrophic lakesLow levels of nutrients and low NPPSteep banks, deep waterEutrophic lakesHigh levels of nutrients and high NPPMesotrophic lakes (meso = middle)Cultural eutrophication leads to hypereutrophic lakes

38The Effect of Nutrient Enrichment on a Lake

39Freshwater Streams and Rivers Carry Water from the Mountains to the Oceans Surface waterRunoff discuss combined sewer overflowsWatershed, drainage basinThree aquatic life zones Source zoneTransition zoneFloodplain zone

40Waterfall

LakeGlacierRain and snowRapidsSource ZoneFig. 8-17, p. 176Transition Zone

TributaryFlood plain

Oxbow lakeSalt marshDeltaDeposited sedimentOceanWaterSedimentFloodplain ZoneStepped ArtThree Zones in the Downhill Flow of WaterFigure 8.17Three zones in the downhill flow of water: source zone containing mountain (headwater) streams; transition zone containing wider, lower-elevation streams; and floodplain zone containing rivers, which empty into the ocean.Case Study: Dams, Deltas, Wetlands, Hurricanes, and New OrleansCoastal deltas, mangrove forests, and coastal wetlands: natural protection against storms

Dams and levees reduce sediments in deltas: significance?

New Orleans, Louisiana, and Hurricane Katrina: August 29, 2005

Global warming, sea rise, and New Orleans42

New Orleans, Louisiana, (U.S.) and Hurricane Katrina43Projection of New Orleans if the Sea Level Rises 0.9 Meter

44Freshwater Inland Wetlands Are Vital SpongesMarshesSwampsPrairie potholesFloodplainsArctic tundra in summer45Freshwater Inland Wetlands Are Vital SpongesProvide free ecological and economic servicesFilter and degrade toxic wastesReduce flooding and erosionHelp to replenish streams and recharge groundwater aquifersBiodiversityFood and timberRecreation areas

468-5 How Have Human Activities Affected Freshwater Ecosystems?Concept 8-5 Human activities threaten biodiversity and disrupt ecological and economic services provided by freshwater lakes, rivers, and wetlands.47Human Activities Are Disrupting and Degrading Freshwater SystemsImpact of dams and canals on riversImpact of flood control levees and dikes along riversImpact of pollutants from cities and farms on riversImpact of drained wetlands 48Case Study: Inland Wetland Losses in the United StatesLoss of wetlands has led to increased flood and drought damageLost due to:Growing cropsMiningForestryOil and gas extractionBuilding highwaysUrban development49http://www.whoi.edu/OCB-OA/page.do?pid=32865 (first video ocean acidification.)