by University of Cambridge
A major study of botanic gardens around the world has revealed their struggles with one fundamental aim: to safeguard the world's most threatened plants from extinction.
Researchers analyzed a century's worth of records—from 1921 to 2021—from fifty botanic gardens and arboreta currently growing half a million plants, to see how the world's living plant collections have changed over time.
The results suggest that the world's living collections have collectively reached peak capacity, and that restrictions on wild plant collecting around the world are hampering efforts to gather plant diversity on the scale needed to study and protect it.
There is little evidence that institutions are managing to conserve threatened plants within collections, on a global scale, despite accelerating rates of elevated extinction risk. The findings imply that tackling the loss of biodiversity has not been prioritized across the world's botanic gardens as a collective - a fact the researchers say must be urgently addressed.
Curator of Cambridge University Botanic Garden Professor Samuel Brockington, who led the work, said, "A concerted, collaborative effort across the world's botanic gardens is now needed to conserve a genetically diverse range of plants, and to make them available for research and future reintroduction into the wild."
In their report, published in the journal Nature Ecology and Evolution, the researchers say the Convention on Biological Diversity (CBD) has effectively halved the level at which plants are being collected from the wild, and also created obstacles to the international exchange of plants.
Brockington, who is also Professor of Evolution in the University of Cambridge's Department of Plant Sciences, said, "The impact of the Convention on Biological Diversity is a remarkable demonstration of the power and value of international agreements. But it seems to be preventing individual botanic gardens from working with many globally threatened plant species that we could help save from extinction."
