Christmas trees absorb super greenhouse gas methane

Christmas trees are absorbing methane, a
super greenhouse gas that they were
previously
suspected of emitting, scientists claim.
The discovery that some trees are
absorbing methane comes from Elin
Sundqvist and colleagues at Lund
University and Stockholm University in
Sweden.
They did forest and laboratory
measurements and analysed gases being
exchanged by tree branches of pine,
spruce and birch trees under a variety of
conditions, Discovery News
reported.
"In contrast to earlier studies of CH4
(methane) exchange by plants, we find a
net consumption by all plants studied
both in situ and in the laboratory,"
researchers concluded.
The discovery could offer a new
explanation to an observed levelling off of
methane concentrations in Earth's
atmosphere, the researchers said.
Earlier, work they cited suggested that
the methane levels were slowing as a
result of less fossil fuel burning while
another study suggested that maybe
there were fewer microbes
making methane in the Northern
hemisphere.
"Our results offer a third explanation:
that an increasing amount of CH4 has
been taken up by vegetation during the
last decades as a consequence of
increased greenness," the
researchers said.
In other words, the observed increases in
vegetation (greening) could mean trees
are working harder at absorbing methane.
The study was published in the journal
Geophysical Research Letters.