Botanists sound plant extinction alert

Posted: 19 September 2006

With fears that one in four of the world¹s plant species could already be on the brink of extinction from the effects of global climate change ­ and as many as half of the planet¹s estimated 400,000 plant species facing a similarly bleak future ­ a group of leading plant scientists have called for a global action plan to tackle the impending crisis.

"While the impact of climate change on iconic animal species, such as polar bears, is well recognised," says Sara Oldfield, Secretary General of Botanic Gardens Conservation International (BGCI), which is co-ordinating the initiative, "the threat that global warming poses to plant diversity is often overlooked and this could have serious consequences for the future of the planet."

This new declaration from The Gran Canaria Group, whose membership is drawn from biodiversity conservation organisations around the world, calls on the international community to take urgent action to protect global plant diversity. It sets out guidelines for action and stresses the role of botanic gardens in delivering the conservation message to their over 200 million annual visitors and in safeguarding their collections of wild plants as native habitats vanish.

Climate change concerns include the use of natural vegetation in water management and carbon offsetting and the vital defensive work of coastal ecosystems in the face of rising sea levels and extreme weather events.

Climate models

The declaration calls for immediate conservation action to protect plant species most at risk from climate change. Priority must also be givento:

  • Development of more detailed climate change models to detect potentially threatened species
  • Use of adaptive management strategies in vulnerable ecosystems
  • Management of existing natural vegetation to maintain carbon stocks and the monitoring of new plantings intended to offset carbonemissions to ensure their ecological suitability.
The group argues for a re-definition of the Global Strategy for Plant Conservation (GSPC), adopted by the UN in 2000, to respond more effectively to the realities of climate change. And it wants the Global Partnership for Plant Conservation (GPPC)to be closely involvedin this process.

Food crops The terrifying implications of plant extinctions for the future of humankind and the wellbeing of the planet simply cannot be underestimated, thescientists believe and time, they argue, is running out.

A recent study of four of the world¹s most important food crops, rice, potato, peanut and cowpea, predicts that climate change over the next fifty years will have a devastating impact on their wild relatives, which harbour the genetic diversity that may enable cultivated crops to adapt to changing climaticconditions. By 2055, says the research, up to a quarter of all potato, peanut and cowpea species could become extinct and over 50 per cent of the land area currently suitable for their cultivation could be gone. "Maintaining the genetic diversity that exists among the wild plant population is absolutely essential if we are to have any chance of mitigating the effects of climate change," says Emile Frison, Director General of the International Plant Genetic Resources Institute (IPGRI), a co-signatory of the declaration. "And this is not just a plant problem, but a human one too. Plants are key to human survival, not just for food, but medicines and many other essential materials." And as environments change faster than plant species can migrate, scientists estimate that in less than 80 years up to half of Europe¹s plant species could be under threat and a massive 60% of mountain species may have vanished. "We have to step up to the challenge now, at every level, if we are to make a difference," warns BGCI¹s Sara Oldfield. "The impact of global climate change on plants and habitats is already being felt and unless we do something about it urgently, the implications for all life on earth are bound to be severe." Source: BCGI, September 7th 2006 A PDF of the Gran Canaria Declaration II on Climate Change and Plant Conservation is available at www.bgci.org