[permaculture] BBC Nature - Man-made noise disrupts the growth of plants and trees

Lawrence London lfljvenaura at gmail.com
Wed Mar 21 09:07:39 EDT 2012

BBC Nature - Man-made noise disrupts the growth of plants and trees

Man-made noise disrupts the growth of plants and trees By Victoria Gill Science
reporter, BBC Nature
[image: Pinus edulis foliage and cones (c) snowpeak via wikimedia commons] The
Pinon pine could suffer from high levels of artificial noise
 Continue reading the main
story<http://www.bbc.co.uk/nature/17457323#story_continues_1> Related

   - Traffic noise is 'bad for
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 It alters birdsong and can make it difficult for some predators to hunt,
and now it seems that man-made noise also affects plants.

A US team found that industrial noise disrupted the behaviour of animals
that pollinate plants and disperse seeds.

This, they suggest, could be slowly transforming our landscape, especially
by changing the dispersal of slow-growing trees.

The study is published in the Royal Society Proceedings

The team, led by Clinton Francis from the National Evolutionary Synthesis
Center (NESCent) in North Carolina, tested the effects of industrial noise
on wildlife in Rattlesnake Canyon Habitat Management Area (RCHMA), New

This large forested area has a high density of natural gas wells, providing
scientists with a unique setting that allowed them to study the effects of
noise without some of the "confounding factors" often associated with noisy
areas, such as roadways and artificial light.
 Continue reading the main
“Start Quote

Fewer pinon pine trees would mean less critical habitat for the hundreds of
species that depend on them for survival”

Clinton Francis NESCent

   - Coniferous_forest videos, news and

 In the first of two experiments, the team focused on birds, which, they
explained, "are considered to be especially sensitive to noise pollution
owing to their reliance on acoustic communication".

They placed patches of artificial hummingbird-pollinated flowers in noisy
and quiet areas.

These convincing flower copies contained tubes of nectar, enabling the
researchers to track exactly how much sugary fluid was consumed by visiting

Industrial din, the scientists discovered, actually increased the activity
of the birds. One species in particular - the black-chinned
hummingbird (*Archilochus
alexandri*) - made five times more visits to noisy sites than quiet ones.

Dr Francis explained that these hummingbirds might prefer noisy sites
because another bird species that prey on their nestlings, such as western
scrub jays, tend to avoid them.
Silent growth
[image: Rattlesnake Canyon Habitat Management Area] Natural gas wells in a
forested area created the ideal setting to test the impact of noise on

In a second set of experiments, the team investigated the effect of noise
on a species of tree that makes up much of the area's forest habitat - the
Pinon pine (*Pinus edulis*).

The team scattered pine cones beneath 120 trees in noisy and quiet sites,
and used a motion-triggered camera to record the animals that took the

Over three days, several animals visited the sites to take seeds, including
mice, chipmunks, squirrels, birds and rabbits. Most significantly though,
mice much preferred noisy sites, whereas western scrub jays avoided them

This, the researchers explained, could be very bad news for the trees.
 Continue reading the main
story<http://www.bbc.co.uk/nature/17457323#story_continues_3> Noisy
[image: Bat foraging near a motorway (Image: Stefan Greif/ Dietmar Nil)]

   - Predators that rely on sound to navigate and hunt are particularly
   susceptible to the effects of man-made noise. Scientists recently found
   that noise from traffic reduces bats' ability to locate

   - The effects of man-made noise on wildlife are not confined to land.
   Researchers recently found evidence of increased levels of a stress
   hormone in right whales in response to noise from nearby

   - Find out more about animals' use of sound to

 The seeds that are eaten by mice, Dr Francis explained, don't survive the
passage through the animal's gut. So an increase in mouse populations near
noisy sites could mean that fewer seeds germinate in those areas.

In contrast, one western scrub jay can take hundreds or even thousands of
seeds and hide them in the soil to eat later in the year. Some of these
will eventually germinate.

The team went on to count the number of pine seedlings and found that they
were four times as abundant in quiet sites compared with noisy ones.

"Fewer seedlings in noisy areas might eventually mean fewer mature trees,
but because pinon pines are so slow-growing the shift could have gone
undetected for years," Dr Francis explained.

"Fewer pinon pine trees would mean less critical habitat for the hundreds
of species that depend on them for survival."

The researchers concluded: "Noise pollution is growing [and] this study
emphasises that investigators should evaluate the ecological consequences
of noise alongside other human-induced environmental changes that are
reshaping human-altered landscapes worldwide."
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noise'<http://www.bbc.co.uk/news/science-environment-16926005> 08

 Related Internet links

   - Noise pollution alters ecological services: enhanced pollination and
   disrupted seed dispersal, Proceedings of the Royal Society

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