Yesterday I mentioned those seas of plastic junk in Pacific and Atlantic Oceans...here is some more...
HEY, whaddya know, I found a "contrarian " view which you might as well see...All these phenomenona should be discussed and talked about as much as possible, and if some people disagree with what has been said so far, let the other people come back with more evidence to prove their point....
This comes from this website
http://io9.com/5911969/lies-youve-been-told-about-the-pacific-garbage-patch
You've probably heard of the "Pacific garbage patch," also called the
"trash vortex." It's a region of the North Pacific ocean where the
northern jet stream and the southern trade winds, moving opposite
directions, create a vast, gently circling region of water called the
North Pacific Gyre — and at its center, there are tons of plastic
garbage. You may even have seen this picture of the garbage patch, above
— right? Wrong.
That image,
widely mislabeled as a shot of the Pacific garbage patch, is actually
from Manila harbor. And it's just one of many misconceptions the public
has about what's really happening to plastics in the ocean. We talked
with Scripps Institution marine biologist Miriam Goldstein, who has just
completed a study of how plastic is changing the ecosystem in the North
Pacific Gyre, about myths and realities of the Pacific garbage patch.
"That picture of the guy in the canoe has been following me around my
whole career!" Goldstein laughed when I brought it up. "I think it's an
example of media telephone, where somebody wanted something dramatic to
illustrate their story — and then through the magic of the internet, the
picture got mislabeled." Goldstein has gone on several research trips
to the garbage patch, 1,000 miles off the coast of California, and has
even swum in it. "We have never seen anything like that picture," she
asserted. "I've never seen it personally, and we've never seen it on
satellite."
MYTH: There is a giant island of solid garbage floating in the Pacific.
FACT: There are millions of small and microscopic pieces of plastic, about .4 pieces per cubic meter, floating over a roughly 5000 square km area of the Pacific. This amount has increased significantly over the past 40 years.
FACT: There are millions of small and microscopic pieces of plastic, about .4 pieces per cubic meter, floating over a roughly 5000 square km area of the Pacific. This amount has increased significantly over the past 40 years.
In reality,
Goldstein said, most pieces of garbage in the Pacific are "about the
size of your pinkie fingernail." Though she and her team have found some
larger pieces of plastic, like buoys and tires, most are microscopic.
What's alarming about them isn't their size, but the sheer amount of
plastic. To figure out how much there really is, she and her team have
trawled the surface of the ocean in random locations over a 1700 square
mile region in the gyre. Once a day, they drag a very fine, specialized
net behind the boat. On one such sampling trip, she and her team found
plastic pieces in 117 out of 119 random samples. On another, they found
plastic in all 28 samples they took.
This
is a video of Goldstein in 2010, talking about some of the group's
earlier research trips to collect samples from the surface of the ocean
in the North Pacific Gyre.
Since the
1970s, scientists have been using the same sampling methods — and the
same kinds of trawling nets, invented by oceanographer Lanna Cheng — to
measure the amount of plastic in the ocean. So Goldstein and her
colleagues are able to make historical comparisons, and measure
increases in plastic density. In a recent paper,
they write, "Microplastic debris in the North Pacific increased by two
orders of magnitude between 1972–1987 and 1999–2010 in both numerical
and mass concentrations."
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MYTH: All this plastic is killing animals.
FACT: Some animals are being harmed, but others are thriving. Here's why that could be a problem.
FACT: Some animals are being harmed, but others are thriving. Here's why that could be a problem.
Nobody who
studies ocean ecosystems would ever argue that this plastic isn't
harmful. But many documentaries and articles about the garbage patch
make it seem as if the main problem is that the garbage is killing
animals. Birds and fish mistake the plastic for food, eat it, and then
slowly starve to death. Goldstein points out that there is clear
evidence that both birds and fish are eating the plastic, but it's very
hard to draw conclusions about whether eating it is killing them.
Generally, scientists are only able to examine the stomachs of animals
who are already dead. "Some studies of albatrosses show plastic
correlating with poor nutrition — and you do see a lot of dead chicks
with their stomachs absolutely stuffed with plastic," Goldstein
explained. The problem is that we don't know whether there are also
birds who eat the plastic and survive. "We're not going to go around
killing baby albatrosses to examine their stomach contents," she added.
This is an
even more difficult issue when it comes to fish, since she and many
other researchers have found living fish with plastic in their stomachs.
It's not clear whether these fish are suffering malnutrition, or are
unharmed by eating plastic because they can just pass it out in their
excrement. Fish digestive systems are a lot different from those of
birds, so it's possible that what's harmful to the albatrosses isn't
affecting the fish as much.
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And finally, there is a class of creatures who are actually thriving as
a result of the plastic influx. These are water skater insects, small
crabs, barnacles, and invertebrates called bryozoans, who live on hard
surfaces in the water. Some of them, like the barnacles and bryozoans,
can do a lot of damage to ship hulls and have caused harm in other
ecosystems they've invaded. Usually, these creatures lead a hardscrabble
life, barely making it in the deep ocean where hard surfaces are
limited to, as Goldstein put it, "the odd floating tree trunk, rare
shells, feathers, or pieces of pumice." But now, with all the plastic
floating around, these once-rare creatures are enjoying a boom time.
In her recent paper,
Goldstein and her colleagues offer persuasive evidence that water
skaters are laying their eggs on pieces of plastic in much greater
numbers than ever before. Does this mean a glut of water skaters? Not
necessarily. Their eggs are large and yellow, which means they stand out
in a world of clear blue water. Possibly what's happening is that all
these eggs are easy prey for fish and crabs who eat them. No matter
what's happening to these eggs, we're going to see an imbalance in this
ecosystem, where suddenly a lot more water skaters or crabs are
competing with the locals for more food.
Expand
MYTH: The plastisphere is killing the ocean.
FACT: The plastisphere is an ecosystem out of balance.
FACT: The plastisphere is an ecosystem out of balance.
The "plastisphere" is a term coined by marine biologist Erik Zettler
to describe the creatures — like water skaters — who thrive in an
environment with hard surfaces in the water. They are similar to
creatures who cling to piers or the hulls of ships. Before human-made
hard surfaces were everywhere, they would have lived on rocks or
flotsam. The problem with the plastisphere is that it's radically
changing the balance of a sea ecosystem that was once mostly just open
ocean creatures.
"One thing
that people worry about is that hard surfaces can transport invasive
species," Goldstein said. "Some animals are good at hitching a ride and
they can be destructive. By adding big chunks of plastic these species
can move around better, and could be introduced to places like the
Northwest Pacific Islands, where there are some of the best coral reefs
in the world." In other words, the plastisphere isn't destroying the
ocean ecosystem — the creatures who ride on the plastic are. We're
witnessing an ecosystem that is slowly falling off balance.
For now,
the open ocean is still mostly inhabited by lantern fish. "There's one
lantern fish for every cubic meter of ocean," Goldstein explained,
noting that these fish are probably more common than the pieces of
plastic her team has sampled. But if trends continue, we're going to see
more plastic than fish. And with that plastic will come more invasive
species, more water skaters, and more creatures to eat the water
skaters' eggs. The danger is that this could alter the open ocean
forever — and destroy all the native life there that has kept the oceans
healthy for thousands of years.
Read Goldstein, et. al.'s paper about water skaters in Biology Letters.
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