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1、BiodiversityvalueDirectvalueIndirectvalueBiodiversityvalueDirectvalueProvidefoodandenergy.Providerichresourcesofmedicinalherbs.Provideindustrialrawmaterials.BiodiversityvalueIndirectvalueMaintainthebalanceandstabilityofecologicalsystemSolarfixedHydrologyregulationClimateregulationabsorptionanddecomp
2、ositionofpollutants,StorageofnutrientelementsandpromotenutrientcyclingmaintenanceoftheevolutionaryprocessThreat-ExcessivedeforestationThreat-IndustrialpollutionThreat-ExcessiveexploitationCaseStudyCostaRicasleadingagriculturalproduceshavelongincludedbeefandbananas,whoseproductionandcultivationrequir
3、eextensiveenvironmentalmodification.AtthebeginingThe Quakers relied on milk and cheese for much of their economic activity,They also set aside one-third of their land for conservation. The Quakers efforts, along with contributions from international conservation organizationsProvided the beginnings
4、of what is today the Monteverde Cloud Forest Biological Reserve. Quakers: Quakers(orFriends,astheyrefertothemselves)aremembersofafamilyofreligiousmovementscollectivelyknownastheReligious Society of Friends.TheQuakersmakeitstartThis privately managed 10,500-ha (26,000-acre) reserve was established in
5、 1972 to protect the forest and its populations of 2,500 plant species, 400 bird species, 500 butterfly species, 100 mammal species, and 120 reptile and amphibian species, including the golden toad.MonteverdeCloudForestBiologicalReserveIn 1970, the Costa Rican government and international representa
6、tives came together to create the countrys first national parks and protected areas. The first parks centered on areas of spectacular scenery, such asTortuguero National Park essential nesting beaches for the green turtleCahuita National Park protect a prominent coral reef systemPoas Volcano Nationa
7、l ParkSanta Rosa National Park encompassed valuable tropical dry forestInitially the government gave the parks little real support. According to Costa Rican conservationist Mario Boza, in their early years the parks were granted only five guards, one vehicle, and no fundingToday government support i
8、s greater. Fully 12% of the nations area is contained in national parks, and a further 16% is devoted to other types of wildlife and conservation reserves. Costa Ricans, along with international biologists, are working to protect endangered species and recover their populations. The benefits of thei
9、r conservation efforts-not only ecological benefits, but also economic ones. Tourists from around the world now visit Costa Rica, a phenomenon called ecotourism The ecotourism industry draws more than 1 million visitors to Costa Rica each year, provides thousands of jobs to Costa Ricans, and is a ma
10、jor contributor to the countrys economy. Its contributions (40%) outweigh those of industry (22%) and agriculture (13%) combined.CostaRicahasprotectedawidearrayofitsdiversenaturalareas.Thisprotectionhasstimulatedthenationseconomythroughecotourism.Here,visitorsexperienceawalkwaythroughtheforestcanopy
11、inoneofthenationsparksHow Best to Conserve Biodiversity?Most people view national parks and ecotourism as excellent ways to help keep ecological systems intact. Yet the golden toad went extinct despite living within a reserve established to protect it, and climate change does not pay attention to pa
12、rk boundaries. It remains to be seen how effectively ecotourism can help preserve natural systems in Costa Rica in the long term. As forests outside the parks disappear, the parks are beginning to suffer from illegal hunting and timber extraction. The parks are still underprotected and underfunded.
13、Still need more money to preserve habitat, protect endangered species, and restore altered communities to their former conditionWhat lessons can we take from this about the conservation of biodiversity?ConclusionThegoldentoadandotherorganismsoftheMonteverdecloudforesthavehelpedilluminatethefundament
14、alsofevolutionandpopulationecologythatareintegraltoenvironmentalscience.Theevolutionaryprocessesofnaturalselection,speciation,andextinctionhelpdetermineEarthsbiodiversity.UnderstandinghowecologicalprocessesworkatthepopulationleveliscrucialtoprotectingbiodiversitythreatenedbythemassextinctioneventManybiologistsmaintainisalreadyunderwayIncludeyou?
