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Section 4
You will hear a university teacher giving his
students some information about a research
project.
In my presentation today, I’m talking about the
conservation of endangered species of tree, and in
particular the work of a group of scientists from
Edinburgh in Scotland.
A small team of conservationists from Edinburgh,
has been involved in a project called Iconic, which
aims to save some of the world’s most endangered
trees from extinction. The trees are conifers and
they grow in the wild in Chile in South America,
where they once occupied large areas of the
country’s coastal mountains. Today only tiny
fragments of the natural forest remain.
Members of the project team have been to South
America on a mission to gather seeds from the few
trees that survive in the wild. Priority was given to
trees that are growing in a valley that will soon be
flooded to make way for a hydro-electricity scheme.
The project aims to save the trees from extinction
and because trees take a long time to grow, it's a
very long-term one.
The seeds of conifer trees grow in cones. Out in
Chile, the team found collecting the cones quite
simple. There was no need for climbing because
few of the targeted species are high-growing trees
with tall canopies. This meant that it was possible to
gather the cones by hand. Some of the species, like
the one called Fitzroya should be very tall trees, but
the remnant populations contain mostly small trees
with low branches. Fitzroya can reach about 45
metres, but there are few trees of that size left in
Chile, and the team only found a few trees left
exceeding 15 metres in height. The team typically
gathers around fifty seeds from each species, and
takes samples from between five and ten trees of
each.
One of the problems they faced was that the seeds
they collect might be low in fertility, leading to poor
germination. Where they believed this was likely,
the team supplements the seed by taking cuttings.
However, they always take care to select parent
plants for seed collections which they believe
contain good seed. As the project leader pointed
out to me, it’s easy to leave Scotland with targets
for the number of seeds that will be collected, but in
practice there’s a need to be flexible. It’s often a
matter of responding to what you find.
So, on to the next stage in the process. Once
harvested, the seeds and cones are transported
back to Scotland, where each seed is logged in a
database, where it is given its identification tag, with
information on where and when it was collected.
Eventually seeds will be selected from this
database and used in the cultivation of young plants
in Scotland.
Once established, the young trees will be planted
out in plantations in Scotland. But initially, the seed
will be germinated under what are called controlled
conditions. These young trees and the seeds they
themselves go on to produce can then form the
basis of a long-term cultivation programme in which
seeds can be returned to Chile, helping to create a
healthy population of trees there for the future.
So why is this project, and projects like it,
important? This is by no means a solution to the
problems of deforestation and the loss of specific
species. Doing this sort of rescue work is what can
only be called a last resort for saving depleted
natural populations. As well as saving threatened
populations and conserving important genotypes,
the Scottish project team is also gathering essential
information about tree growth
– data which might
otherwise have been lost. To be able to effectively
restore natural forests and ecosystems, we have to
know how to cultivate the plants.
It is this horticultural knowledge that is going to
prove so vital in the future restoration and
management of native areas. This type of project is
part of a wider discipline known as ‘restoration
ecology’, where, as the name suggests, whole
ecosystems are restored artificially. And the key to
this whole process, to almost all the world's
ecosystems, is plants.
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