专业英语-生态学教材.ppt

Biodiversityvalue DirectvalueIndirectvalue Biodiversityvalue DirectvalueProvidefoodandenergy Providerichresourcesofmedicinalherbs Provideindustrialrawmaterials Biodiversityvalue IndirectvalueMaintainthebalanceandstabilityofecologicalsystemSolarfixedHydrologyregulationClimateregulationabsorptionanddecompositionofpollutants Storageofnutrientelementsandpromotenutrientcyclingmaintenanceoftheevolutionaryprocess Threat Excessivedeforestation Threat Industrialpollution Threat Excessiveexploitation CaseStudy CostaRica sleadingagriculturalproduceshavelongincludedbeefandbananas whoseproductionandcultivationrequireextensiveenvironmentalmodification Atthebegining TheQuakersreliedonmilkandcheeseformuchoftheireconomicactivity Theyalsosetasideone thirdoftheirlandforconservation TheQuakers efforts alongwithcontributionsfrominternationalconservationorganizationsProvidedthebeginningsofwhatistodaytheMonteverdeCloudForestBiologicalReserve Quakers Quakers orFriends astheyrefertothemselves aremembersofafamilyofreligiousmovementscollectivelyknownastheReligiousSocietyofFriends TheQuakersmakeitstart Thisprivatelymanaged10 500 ha 26 000 acre reservewasestablishedin1972toprotecttheforestanditspopulationsof2 500plantspecies 400birdspecies 500butterflyspecies 100mammalspecies and120reptileandamphibianspecies includingthegoldentoad MonteverdeCloudForestBiologicalReserve In1970 theCostaRicangovernmentandinternationalrepresentativescametogethertocreatethecountry sfirstnationalparksandprotectedareas Thefirstparkscenteredonareasofspectacularscenery suchas TortugueroNationalParkessentialnestingbeachesforthegreenturtle CahuitaNationalParkprotectaprominentcoralreefsystem PoasVolcanoNationalPark SantaRosaNationalParkencompassedvaluabletropicaldryforest Initiallythegovernmentgavetheparkslittlerealsupport AccordingtoCostaRicanconservationistMarioBoza intheirearlyyearstheparksweregrantedonlyfiveguards onevehicle andnofunding Todaygovernmentsupportisgreater Fully12 ofthenation sareaiscontainedinnationalparks andafurther16 isdevotedtoothertypesofwildlifeandconservationreserves CostaRicans alongwithinternationalbiologists areworkingtoprotectendangeredspeciesandrecovertheirpopulations Thebenefitsoftheirconservationefforts notonlyecologicalbenefits butalsoeconomicones TouristsfromaroundtheworldnowvisitCostaRica aphenomenoncalledecotourism Theecotourismindustrydrawsmorethan1millionvisitorstoCostaRicaeachyear providesthousandsofjobstoCostaRicans andisamajorcontributortothecountry seconomy It scontributions 40 outweighthoseofindustry 22 andagriculture 13 combined CostaRicahasprotectedawidearrayofitsdiversenaturalareas Thisprotectionhasstimulatedthenation seconomythroughecotourism Here visitorsexperienceawalkwaythroughtheforestcanopyinoneofthenation sparks HowBesttoConserveBiodiversity Mostpeopleviewnationalparksandecotourismasexcellentwaystohelpkeepecologicalsystemsintact Yetthegoldentoadwentextinctdespitelivingwithinareserveestablishedtoprotectit andclimatechangedoesnotpayattentiontoparkboundaries ItremainstobeseenhoweffectivelyecotourismcanhelppreservenaturalsystemsinCostaRicainthelongterm Asforestsoutsidetheparksdisappear theparksarebeginningtosufferfromillegalhuntingandtimberextraction Theparksarestillunderprotectedandunderfunded Stillneedmoremoneytopreservehabitat protectendangeredspecies andrestorealteredcommunitiestotheirformercondition Whatlessonscanwetakefromthisabouttheconservationofbiodiversity Conclusion ThegoldentoadandotherorganismsoftheMonteverdecloudforesthavehelpedilluminatethefundamentalsofevolutionandpopulationecologythatareintegraltoenvironmentalscience Theevolutionaryprocessesofnaturalselection speciation andextinctionhelpdetermineEar