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By PENNY FANNIN SCIENCE REPORTER The Age, Australia
 Changing
global weather patterns appear to have caused the treeline around
Mount Hotham and Falls Creek to creep uphill.
Research by
scientists at La Trobe University has found that during the past
25 years the treeline in alpine Victoria has moved up to 40 metres.
John Morgan,
an alpine plant ecologist in the university's school of botany,
said snow gums in the sub-alpine forest had been stable for many
years but new trees had become established in the past quarter-century.
"We are
seeing trees growing where they have never grown before,"
he said. "Since 1975 something has happened that was not
going on in the past."
By a process
of deduction Dr Morgan has identified temperature change as the
most likely cause of the new plant growth.
"Cold
temperatures limit these trees and if they're now growing in areas
where previously they could not then it's because it's not so
cold."
Weather records
from the area showed that temperature had increased and the length
of the snow season had decreased.
Young snow
gums, which were growing in previously bare regions, were healthy
and some were up to eight metres high, he said.
"A mean
annual temperature change of one degree might have been enough
to let these things get through when they previously could not."
Dr Morgan
does not believe his observations are just a local phenomenon
as they have been made at four sites around Mount Hotham and two
near Falls Creek.
In the mid-1990s
a survey of mountains in Germany showed that the number of alpine
plant species had fallen - one of the first signs that biological
systems responded to global warming.
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