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https://theconversation.com/one-third-of-the-worlds-tree-species-are-threatened-with-extinction-here-are-five-of-them-167749>
"One in three of the world’s tree species are at risk of becoming extinct,
according to a recent report by the Global Tree Assessment – the first attempt
to estimate the conservation status of all of Earth’s trees.
Well-known species, including magnolias, oaks and maples are among those at
risk. More than 400 species have fewer than 50 individuals remaining in the
wild, and 142 tree species are already extinct. Human activity is the
overwhelming culprit, especially forest clearance for farming, logging for
timber and the spread of invasive pests and diseases.
When myself and colleagues first came up with the idea of a worldwide
assessment of tree species in 2015, it seemed like an impossible task. Back
then, nobody even knew how many there were, let alone how they were all faring.
The first task was to make a list of all tree species that have been described
in scientific literature. It turns out there are nearly 60,000, most of which
live in tropical forests, and scientists continue to describe new species each
year.
We then had to determine which of these are under threat of extinction. Given
the huge number of species, this was a much bigger task than any conservation
assessment undertaken previously. We created a global network of more than 500
experts, each assessing the species they were most familiar with, and the
report is the result of that enormous collaborative effort which took five
years to complete.
There are twice as many threatened tree species globally than threatened
mammals, birds, amphibians and reptiles combined. But trees are also food and
habitat for at least half of the Earth’s known land-based plants and animals.
Losing tree species can cause cascades of extinction among the many species
that depend on them.
Trees are very valuable to people too. More than one-fifth are used as a source
of food, fuel, timber or medicine. Others have important cultural and religious
value. Worryingly, some of the most useful and significant species are among
those facing extinction. Here are five of them."
Cheers,
*** Xanni ***
--
mailto:xanni@xanadu.net Andrew Pam
http://xanadu.com.au/ Chief Scientist, Xanadu
https://glasswings.com.au/ Partner, Glass Wings
https://sericyb.com.au/ Manager, Serious Cybernetics
