Geoscience Reference
In-Depth Information
wide distribution of most plants and invertebrates within the maritime Antarctic,
despite clear evidence that most areas that are now seasonally ice free must have
been covered at most 10
-
15 000 years ago, and in many cases much more recently.
Evidence of contemporary colonisation is seen in the form of new populations on
previously barren ground, and new species records from better-known locations.
Particularly impressive evidence is provided in studies of heated ground at a few
volcanically active sites around Antarctica. These sites are, by de
nition, short-lived
and small, but they host exceptional bryophyte and arthropod communities that
include species not otherwise found in Antarctica.
Climate change and other human impacts
Antarctica
uence
until recent centuries and decades. The terrestrial environments of Antarctica and
even the milder sub-Antarctic islands have not yet been subjected to human
exploitation as seen on all other continents worldwide. However, there have
undoubtedly been fundamental impacts, commencing with the land-based activities
associated with the sealing and whaling industries in the sub- and maritime
Antarctic regions, and with attempts at farming activities and the introductions of
alien species on some sub-Antarctic islands.
The
'
s simple isolation provided a very effective barrier to human in
first human landings on the Antarctic Peninsula and the continent itself
took place just over 100 years ago, initiating the
of continental
exploration. Following the post-war International Geophysical Year of 1957
'
Heroic Age
'
-
58,
and the creation of the Antarctic Treaty System in 1961, science became the focus
of human activity on the continent. By 2012, 50 countries had acceded to the
Antarctic Treaty, and many scienti
c research stations had been established around
the continent. Over the last 40 years, Antarctica has achieved increasing prominence
on the tourist map of the world, and numbers of visitors continue to increase
rapidly. There is now a realisation that a combination of the very limited extent
of ice-free ground available in Antarctica, the concentration of both marine and
terrestrial biota in these locations and the fragility of terrestrial ecosystems in the
face of physical disturbance, inevitably leads to a con
ict of interest between the
viability of ecosystems and human activities. Human presence has inevitably
disturbed and, locally, destroyed areas of terrestrial habitat.
Biological introductions
The introduction of non-indigenous (
) organisms is an almost inevitable
corollary of human contact with any ecosystem worldwide, and Antarctica is no
exception. Many animals, plants and microbes are capable of surviving and
'
alien
'
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