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Hotspot conservation will not protect global biodiversity Rhett Butler, mongabay.com December 11, 2006 The concept of biological hotspots has served as a fundamental principle guiding conservation efforts over the past generation. A new study, published in the Dec. 15 online edition of the Proceedings of the National Academy of Sciences (PNAS), argues this may be a mistake and that conservation efforts based on hotspots will not effectively preserve biodiversity. Biodiversity hotspots are geographic areas that contain high levels of species diversity but are threatened with extinction. First identified by British ecologist Dr. Norman Myers in two articles in The Environmentalist (appearing in 1998 and 1990), the principles of biodiversity hotspots have been the basis for conservation efforts by Conservation International (CI) and other leading environmental groups. Today over half of the world’s plant species and 42 percent of all terrestrial vertebrate species are endemic to the world's 34 biodiversity hotspots according to CI. These hotspots account for more than 60 percent of the world's known plant, bird, mammal, reptile, and amphibian species. While there's no doubt that these areas house a significant portion of the planet's biological diversity, the new PNAS paper argues that the three factors that usually determine hotspots -- the number of total species (species richness), the number of unique species (endemism), or the number of species at risk (threat of extinction) -- do not necessarily overlap on a global scale. The results raise similar issues to those presented in a paper published in the November 2, 2006 issue of the journal Nature which found a geographical discrepancy in hotspots of endangered species from different groups (i.e. birds, amphibians, mammals) -- geographical areas with a high concentration of endangered species from one group do not necessarily have high numbers from other groups.
"Hotspots, which have played a central role in the selection of sites for reserves, require careful re-thinking," the authors wrote. "Assigning global conservation priorities based on hotspots is at best a limited strategy." "We found that if you use species richness as a criterion, you're not going to protect the endemic or endangered species," said lead author Gerardo Ceballos. "So the 'hotspot' approach, which was extremely valuable in focusing attention on species diversity in the past, has limitations. What's needed is a more comprehensive analysis that also takes into account the species that live outside the hotspots." The authors say that because most of the world's biodiversity persists in some of the world's poorest countries where conservation is not a top priority, there is a great need to develop strategies for maintaining biodiversity in human-disturbed landscapes, a discipline known as "countryside biogeography." Further, say the authors, climate change could well cause species to shift their ranges outside areas that are currently protected. "The likelihood of species migrations in response to global climate change adds further complexity to the development of conservation strategies, and further limits the present usefulness of the classic hotspot approach," they wrote. "Most of the significant habitats that need protecting are outside of hotspots, and we should do a better job managing them properly," added Ceballos. Going forward, Ceballos and Ehrlich say that new protected areas should be selected based on more comprehensive criteria. “Hotspots tem o valor para o conservation mas são completamente limitados,” mongabay.com dito Ceballos através do email. “Hoje nós podemos fazer avaliações melhores para determinar locais da prioridade para o conservation no nível do mundo. Tais análises indicam um scenario mais complexo do que apenas hotspots protegendo. Bàsicamente, nossa sugestão é que as áreas protegidas novas devem ser selecionadas por causa de suas concentrações de espécies endemic ou postas em perigo, seu complementarity, respresentação de populações locais, e proteção de serviços do ecosystem.” “Eu propus três coisas tentar minimizar a população e as extinções da espécie,” continuaram Ceballos, sumariando seu trabalho. “Um, áreas mais protegidas reservadas, dentro e fora dos hotspots. Dois, melhoram o valor da matriz seminatural (isto é paisagens dominadas por atividades humanas) para o conservation do biodiversity. Três, tentativa para reduzir a densidade de população e a pobreza humanas.” Ceballos e Ehrlich adicionaram aquele além de reservar áreas protegidas adicionais e fazendo habitats humano-alterados mais hospitable ao biodiversity, os esforços reduzir pressões humanas no biodiversity e os ecosystems restantes são chave. “Todos os biólogos do conservation devem tentar encontrar maneiras de reduzir os excitadores básicos da perda do biodiversity: crescimento da população, overconsumption pelos rich, e o uso de tecnologias defeituosas e de sistemas socio-econômico-políticos,” conclíram. Este artigo usa citações e a informação do papel de PNAS e de uma notícia libera-se da universidade de Stanford. Recomendar este artigo? Comentários? Original version (in English) | |
MONGABAY.COM Mongabay.com promove a apreciação da natureza e dos animais selvagens, quando também examinar o impacto de emergir tender no clima, na tecnologia, na economia, e nas finanças no conservation e no desenvolvimento. Estes artigos são escritos em inglês mas traduzidos automaticamente. Uma tradução profissional aparece aqui. Se você gostar de ajudar com tradução, contatar-me por favor. Eu estou procurando um interno para ajudar com tradução.
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