"Long before it's in the papers"
June 04, 2013


Over a fifth of plant species may face extinction threat

Sept. 28, 2010
Courtesy of Royal Botanic Gardens Kew
and World Science staff

One in five plant spe­cies are threat­ened with ex­tinc­ti­on, put­ting plants on a par with mam­mals in terms of their risks of dy­ing out, a study has found.

The study was con­ducted by the Nat­u­ral His­to­ry Mu­se­um in Lon­don, the Roy­al Bo­tan­ic Gar­dens, Kew, U.K. and the In­tern­ati­onal Un­ion for the Con­serv­ati­on of Na­ture.

Based on what the sci­en­tists called a rep­re­sent­a­tive sam­ple of almost 4,000 spe­cies, “this study con­firms what we al­ready sus­pect­ed,” said Ste­phen Hop­per, di­rec­tor of the Bo­tan­ic Gar­dens. “Plants are un­der threat and the main cause is human-induced hab­i­tat loss.” 

The study was billed as mark­ing the first time that the true ex­tent of the threat to the world’s es­ti­mat­ed 380,000 plant spe­cies is known. The find­ings were an­nounced as gov­ern­ments are to meet in Na­go­ya, Ja­pan in mid-October to set new bio­divers­ity tar­gets.

“For the first time we have a clear glob­al pic­ture of ex­tinc­ti­on risk to the world’s known plants,” Hop­per said. “This re­port shows the most ur­gent threats and the most threat­ened regi­ons.” 

The study found that plants are more threat­ened than birds, as threat­ened as mam­mals and less threat­ened than am­phib­ians or corals. The most threat­ened plants are gym­nosperms, group that in­cludes conifers and cy­cads, the re­search­ers said; the most threat­ened hab­i­tat is trop­i­cal rain for­est. Conversi­on of hab­i­tats for ag­ri­cul­ture or live­stock use is mostly to blame for the man-induced hab­i­tat loss that un­der­lies the bulk of the threat, in­ves­ti­ga­tors con­clud­ed.

The stu­dy, known as the Sam­pled Red List In­dex for Plants, is part of a world­wide ef­fort to cre­ate a tool to mon­i­tor the chang­ing sta­tus of the world’s ma­jor groups of plants, fun­gi and an­i­mals.

“The 2020 bio­divers­ity tar­get that will be dis­cussed in Na­go­ya is am­bi­tious, but in a time of in­creas­ing loss of bio­divers­ity it is en­tirely ap­pro­pri­ate to scale up our ef­forts,” Hop­per said. “Plants are the found­ati­on of bio­divers­ity and their sig­nif­i­cance in un­cer­tain cli­mat­ic, eco­nom­ic and po­lit­i­cal times has been over­looked for far too long.”

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One in five plant species are threatened with extinction, putting plants on a part with mammals in terms of their risk of dying out, a study has found. The study was conducted by the Natural History Museum in London and the Royal Botanic Gardens, Kew, U.K. and the International Union for the Conservation of Nature. Based on what the scientists called a representative sample of 4,000 species, “this study confirms what we already suspected,” said Stephen Hopper, director of the Botanic Gardens. “Plants are under threat and the main cause is human-induced habitat loss.” The study was billed as marking the first time that the true extent of the threat to the world’s estimated 380,000 plant species is known, and was announced as governments are to meet in Nagoya, Japan in mid-October to set new biodiversity targets. “For the first time we have a clear global picture of extinction risk to the world’s known plants,” Hopper said. “This report shows the most urgent threats and the most threatened regions. In order to answer crucial questions like how fast are we losing species and why, and what we can do about it.” The study found that plants are more threatened than birds, as threatened as mammals and less threatened than amphibians or corals. The most threatened plants are gymnosperms, group that includes conifers and cycads, the researchers said; the most threatened habitat is tropical rain forest. Conversion of habitats for agriculture or livestock use is mostly to blame for the man-induced habitat loss that underlies the bulk of the threat, investigators concluded. The study, known as the Sampled Red List Index for Plants, is part of a worldwide effort to create a tool to monitor the changing status of the world’s major groups of plants, fungi and animals. “The 2020 biodiversity target that will be discussed in Nagoya is ambitious, but in a time of increasing loss of biodiversity it is entirely appropriate to scale up our efforts,” Hopper said. “Plants are the foundation of biodiversity and their significance in uncertain climatic, economic and political times has been overlooked for far too long.”