More than fifth of world’s plants could vanish, says global study

More than a fifth of the world’s plants are under threat of extinction, a global assessment revealed yesterday.

The analysis indicates that the estimated 380,000 plant species found on earth are as much at risk of disappearing as the planet’s mammals and are more under threat than birds.

Plants are most at risk from the destruction of their habitat by humans, according to the assessment by scientists at Kew, the Natural History Museum and the International Union for Conservation of Nature.

Vegetation is under pressure from human activities across the world – from the destruction of the Atlantic rainforest in South America to slash and burn land clearance in Madagascar, palm oil plantations in Indonesia and intensive agriculture in Europe and the US, the experts warned. The study, the Sampled Red List Index for Plants, indicates that some 80,000 to 100,000 plants could be at risk of extinction globally – more than 50 times the number of species known to be native to the British Isles.

The study looked at a representative sample of 7,000 plants from five major groups of plants, which incorporate mosses, ferns, conifers, flowering plants such as orchids and grasses, and legumes.

Both rare and common species were assessed to give a baseline for how plants were doing, in contrast to the existing IUCN Red List of Threatened Species for plants, which includes just three per cent of species but focuses on ones which are at risk of extinction.

Too little was known about a third of the species in the sample used for the latest index, making it impossible to properly assess them.

The research found that 22 per cent of the 4,000 species which were carefully assessed were classified as critically endangered, endangered or vulnerable to extinction.

A further 10 per cent of plants including the humble snowdrop – a non-native species which has become widely established in the UK but is losing ground in its natural habitat in central and eastern Europe – are not yet threatened but will be without conservation action.

The majority of threatened plant species were found in tropical rainforest, which is home to a wide variety of species but is under great pressure from humans, while islands in the middle of the ocean such as Christmas Island and Bermuda also had a high proportion of threatened species.

Gymnosperms, the plant group containing conifers, were the most threatened group with 36 per cent of species at risk.

The director of the Royal Botanic Gardens, Kew, professor Stephen Hopper, said: “This study confirms what we already suspected, that plants are under threat and the main cause is human-induced habitat loss. “Plants are the foundation of biodiversity and their significance in uncertain climatic, economic and political times has been overlooked for far too long.

“We cannot sit back and watch plant species disappear – plants are the basis of all life on earth, providing clean air, water, food and fuel. All animal and bird life depends on them and so do we.”

The global analysis of the state of plants comes just weeks before governments from around the world meet in Nagoya, Japan, to discuss the state of the world’s wildlife and habitats and set new targets on protecting biodiversity over the next decade.

Global targets to significantly reduce the loss of wildlife by this year have been missed.