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NIS - BIOLOGY

NIS - BIOLOGY. Lecture 18 Biodiversity Ozgur Unal. What is Biodiversity. Look at the pictures below and state which species is the most abundant , which is less abundant . What is Biodiversity.

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NIS - BIOLOGY

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  1. NIS - BIOLOGY Lecture 18 Biodiversity OzgurUnal

  2. What is Biodiversity • Look at thepicturesbelowand • statewhichspecies is themost • abundant, which is lessabundant.

  3. What is Biodiversity • Biodiversityis thevariety of life in an areathat is determinedbythenumber of differentspecies in thatarea. • Entirespeciesmaypermanentlydisappearfromthebiosphere in a processcalledextinction. • Extinctionreducesbiodiversity. What do wemeanbyvariety of life? • Threetypes of biodiversity: • Geneticdiversity • Speciesdiversity • Ecosystemdiversity

  4. GeneticDiversity • Thevariety of genesorinheritablecharacteristicsthatarepresent in a populationcomprisesitsgeneticdiversity. • Thevariety of colorsdemonstrates a form of geneticdiversity. • Somecharacteristicsare not as apparent as color. • Theabilitytotorecoverfrom a disease • Theabilitytotoobtainnutrients • from a newfoodsourceetc.

  5. SpeciesDiversity • Thenumber of differentspeciesandtherelativeabundance of eachspecies in a biologicalcommunity is calledspeciesdiversity. • As youmovefromthe polar regionstotheequator, speciesdiversityincreases. • Howmanydifferent • species can youidentify • in thepicture?

  6. EcosystemDiversity • Thevariety of ecosystemsthatarepresent in thebiosphere is calledecosystemdiversity. • Differentlocationsaroundhteworldhavedifferentabioticfactorsthatsupportdifferenttypes of life.

  7. TheImportance of Biodiversity • Why is conservingbiodiversityimportant? • Whatbenefits do wegetbyconservingbiodiversity? • Economicvalue: • Conservinggeneticbiodiversitymight be helpful in thefuturetoimprovedomesticcropspecies. Example: Teosintecornplants • Beingableto transfer genesmakes it extemelyimportanttomaximizethevariety of genes. • Derivingmedicinesfromplantsandotherorganisms.

  8. TheImportance of Biodiversity • Aestheticandscientificvalue: • Beauifulspeciesandecosystems.. • Scientificallyinterestingtostudy.

  9. NIS - BIOLOGY Lecture 19 ThreatstoBiodiversity OzgurUnal

  10. ExtinctionRates • How long did the dinosaurs live on Earth? • Were they biologically diverse? • How did they become extinct? Did they become extinct by time or all of a sudden? • How do we call it if there is a sudden extinction of a species? Checktheseout! http://video.nationalgeographic.com/video/index.html • Dinosaursbecameextinctbymassextinction. • Massextinctionis an event in which a largepercentage of allspeciesbecomeextinct in a relativelyshortperiod of time. • Table 5.1

  11. ExtinctionRates • How many tigers were living about 15 years ago? How many tigers live now? • Why did they decrease in number? • What term do we use for the species close to extinction? • Assuming that in the next decade these tigers become extinct, is there any similarity between the extinction of the dinosaurs and the extinction of these tigers? What is the difference? http://video.nationalgeographic.com/video/index.html?widgets=unknown%7cSyndicatedVideoPlayer • Thegradualprocess of speciesbecomingextinct is known as background extinction.

  12. ExtinctionRates – Background Extinction Stableecosystems: Naturalprocess of extinctionbytheactivity of otherorganisms, climatechangesornaturaldisasters. Thisnaturalprocess of extinction is not a bigconcern. Increase in the rate of extinctionis a bigconcern! Somescientistspredictthatbetween 1/3 or 2/3 of allanimalandplantspecieswillbecomeextinctbytheend of thiscentury. CheckoutTable 5.2 toseethenumber o fextinctions since 1600. Whyarespecies on islandsaremorevulnerabletoextinction?

  13. FactorsthatThreatenBiodiversity • HomoSapiens • Activities of homosapienschangetheconditions on Earthfasterthannewtraits can evolvetocopewiththenewconditions. • After a massextinction, newspecies can evolveover time andbiodiversityrecovers. • But as humanschangetheconditionsfasterthanevolving rate of species,biodiversitycannotrecover. • Humansalsouseupthenaturalresourcesfortheirownneed, leaving not enoughtosomeotherspecies. • Naturalresourcesareallmaterialsandorganismsfound in thebiosphere, includingmineralsfossilfuels, nuclearfuels, plants, animals, soilcleanwater, cleanairand solar energy. What is themainreasonforthesehighrates of extinction?

  14. FactorsthatThreatenBiodiversity - Overexploitation Overexploitation Overexploitationis theexcessiveuse of speciesthathaveeconomicvalue. Example: Bisons in North Americahavebeenhuntedtothebrink of extinctionbecause of theirmeatandhides. Theywerealsohuntedforsports.

  15. FactorsthatThreatenBiodiversity - Overexploitation Otherexamplessubjecttooverexploitation: Passengerpigeons Ocelot Whiterhinoceros

  16. FactorsthatThreatenBiodiversity – Habitat Loss Habitat Loss Thereareseveralwaysthatspecies can losetheir habitat If a habitat may be destroyedordisrupted, thenativespeciesmighthavetorelocateortheywilldie. • Destruction of habitat: Theclearing of tropicalrainforest has a directimpact on global biodiversity. • Tropicalrainforestsarebeingclearedforagriculture, grazinganimalsetc. • Morethanhalf of allspecieslive in thetropicalrainforestsandtheremoval of therainforestswillcausemanyspecies on Earthtobecomeextinct.

  17. FactorsthatThreatenBiodiversity Disruption of habitat: Habitatsmight be disrupted. Howdoes a decline in thenumber of sealionsandharborsealsaffectotherspecies in Figure 5.11? • Fragmentation of Habitat: • Theseparation of an ecosystemintosmallerpieces of land is calledhabitat fragmentation. • A habitat can be fragmentedbyconstructingroadsorhumanmadebarriers. • If a parcel of land is smaller, it supportsfewerspecies.

  18. FactorsthatThreatenBiodiversity – Habitat Fragmentation Fragmentationreducestheopportunitytoreproducewithindividualsfromanotherarea. Fragmentationalsoincreasesthenumber of parcelsthathaveedgescreatingedgeeffects. Edgeeffectsaredifferentenvironmentalconditionsthatoccuralongtheboundaries of an ecosystem. Forexample: Edges of a forestnear a roadhavedifferentabioticfactors thantheinterior of a forest.

  19. FactorsthatThreatenBiodiversity –Pollution Pollutionandatmosphericchangesthreatenbiodiversityand global stability. Manytypes of pollution: Airpollution, waterpollution, soilpollutionetc. Humanmadedangerouschemicals, pesticidessuch as DDT, areingestedbyorganismswhentheydrinkwateroreatotherorganismsthatcontainthechemical. Thesedangerouschemicalsaccumulate in thetissues of organisms.

  20. FactorsthatThreatenBiodiversity – DDT Carnivores at thehighertrophiclevelsseemto be mostaffectedbythisaccumulationbecause of a processcalledbiologicalmagnification. Biologicalmagnificationis theincreasingconcentration of toxicsubstances in organisms as trophiclevelsincrease in a foodchainorfood web. CheckoutFigure 5.13 Howexactlydoes DDT threatenthesurvival of thefisheatingbirds?

  21. FactorsthatThreatenBiodiversity – DDT

  22. FactorsthatThreatenBiodiversity –Pollution Acidprecipitation:Whenfossilfuelsareburned, sulfurdioxide is releasedintotheatmosphere. Also, fuelsburned in automobileenginesreleasenitrogenoxides in totheatmosphere. Thesecompoundsreactwithwaterandothersubstances in theairtoproducesulfuricandnitricacid. Byprecipitationtheseacidseventuallyfallback on thesurface of Earthanddamageplantsandotherspecies in thesoilbyremovingpotassiumcalciumandothernutrients.

  23. FactorsthatThreatenBiodiversity – Pollution

  24. FactorsthatThreatenBiodiversity –Pollution Eutrophication: A form of waterpollution, calledeutrophication, destroysunderwaterhabitatsforfishandotherspecies. Eutrophicationoccurswhenfertilizers, animalwaste, sewageorothersubstancesrich in nitrogenandphosphorusflowintowaterways. Thesesubstances in waterresult in rapidalgaegrowth. Thesealgaeuseupmost of theoxygenavailable in thewater. Otherorganisms in thewater, as a result, suffocate. Eutrophication is a naturalprocess but humanactivities (dumpingsewage, fertilizers in waterwaysetc.) acceleratethe rate at which it occurs.

  25. FactorsthatThreatenBiodiversity – Pollution

  26. FactorsthatThreatenBiodiversity –IntroducedSpecies Introducedspecies: Nonnativespeciesthatareeitherintentionallyorunintentionallytransportedto a new habitat areknown as introducedspecies. Under normal conditions, predators, parasitesandcompetitionbetweenspecieskeepthenativeecosystem in balance. Whennewspeciesareintroducedinto a newarea, thesecontrollingfactorsare not in place. Introducedspeciesreproduce in largenumbersandbecause of a lack of predatorsandbecomeinvasivespecies in theirnew habitat. CheckFigure 5.15 forimported fire ants in the US.

  27. FactorsthatThreatenBiodiversity –IntroducedSpecies http://video.nationalgeographic.com/video/index.html?widgets=unknown%7cSyndicatedVideoPlayer What do cane toads eat? When and why were they brought to Australia? Why and how are they dangerous to the other species? What term do we use for the species like cane toads? Why is it bad to introduce new species to an ecosystem?

  28. FactorsthatThreatenBiodiversity AssignmentdueFriday: Chooseone of thefactorsthatthreatensbiodiversitybelowandwrite an informativeessay on it. Overexploitation (bisons) Habitat loss (tropicalrainforests) Pollution (acidrain) IntroducedSpecies (fire ants) Youressayshould be morethan 400 wordstyped in MS Word (Times New Roman, 12, 1.5 paragraph) Include at least 2 pictures in youressay. Give as manyrelevantinformation as you can withoutsacrificingconsistency. Make 5 copies of youressayandbringthemwithyou on Fridayto be distributedtoeachperson in theclass.

  29. NIS - BIOLOGY Lecture 20 ConservingBiodiversity OzgurUnal

  30. NaturalResources • Look at thepicturesandtrytoidentifywhichresourcesareverylimited in supplyandwhichare not as limited as others. Morethan 6 billionhumans on Earth Increase in humanpopulation ----> Increase in theneedfornaturalresources

  31. RenewableResources Theresourcesthatarereplacedbynaturalprocessesfasterthantheyareconsumedarecalledrenewableresources. Example: Solar energy, cleanair, cleanwater, agriculturalplantsandanimalsetc. Thesupply of theseresourcesare NOT unlimited. Ifthedemandexceedsthesupply of anyresource, theresourcemightbecomedepleted.

  32. NonrenewableResources Theresourcesthatarefound on Earth in limitedamountsorthosethatarereplacedbynaturalprocessesoverextremelylongperiods of time arecallednonrenewableresources. Example:Fossilfuels, mineral depositsetc. Speciesareconsideredrenewable resourcesuntilthelast of a speciesdie (it is lostforever)

  33. Use of NaturalResources Theconsumption rate of naturalresources is not evenlydistributed. CheckoutFigure 5.16! Developedcountriesconsumemorenaturalresourcesthandevelopingcountries. Why? • As thehumanpopulationincreases, a long-term plan fortheuseandconservation of naturalresources is important. • Oneapproach is sustainableuse. • Sustainableusemeansusingresources at a rate in whichthey can be replacedorrecycledwhilepreservingthelong-termenvironmentalhealth of thebiosphere. • Reducingtheamount of resourcesconsumed, recyclingandpreservingecosystems.

  34. ProtectingBiodiversity WeknowfromSection 5.2 thathumanactivitiesaffectecosystems. Manyeffortsareunderwayworldwidetoslowtheloss of biodiversityandtousenaturalresourcessustainably. InternationalProtectedAreas Biodiversity Hot Spots: (Figure 5.19) Endemicspeciesarespeciesthatareonlyfound in thatspecificgeographiclocation. Theremust be at least 1500 species of vascularplantsthatareendemic. Theregionmusthavelost 70% of itsoriginal habitat. CorridorsBetween Habitat Fragments

  35. ProtectingBiodiversity Biodiversity Hot Spots

  36. RestoringEcosystems CheckoutFigure 5.21 andtrytointerpretthegraph. Howlongdoes it taketorecoverfromsomehumancauseddisasters? Whatarethewaystospeedupthisrecovery time? • Bioremediation:Theuse of livingorganisms, such as prokaryotes, fungiorplantstodetoxify a pollutedarea is calledbioremediation. • Example: Oilspills • Biologicalaugmentation: Addingnaturalpredatorsto a degradedecosystem is calledbiologicalaugmentation. • Example: Ladybugseatingaphids, whichtransmitplantdiseasesthatdestroycrops.

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