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You can only see 1% of all microplastics dumped into the ocean – TNW

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What if the “great ocean garbage patches” were just the tip of the iceberg? While more than ten million tonnes of plastic waste enters the sea each year, we actually see just 1% of it – the portion that floats on the ocean surface. What happens to the missing 99% has been unclear for a while.

Plastic debris is gradually broken down into smaller and smaller fragments in the oceanuntil it forms particles smaller than 5mm, known as microplastics. Our new research shows that powerful currents sweep these microplastics along the seafloor into large “drifts,” which concentrate them in astounding quantities. We found up to 1.9 million pieces of microplastic in a 5cm-thick layer covering just one square metre – the highest levels of microplastics yet recorded on the ocean floor.

While microplastics have been found on the seafloor worldwide, scientists weren’t sure how they got there and how they spread. We thought that microplastics would separate out according to how big or dense they were, in a similar manner to natural sediment. But plastics are different – some float, but more than half of them sink.

Read: [Chemical recycling could be the solution to plastic pollution]

Plastics which once floated can sink as they become coated in algae, or if bound up with other sticky minerals and organic matter. Recent research has shown that rivers transport microplastics to the ocean too, and laboratory experiments revealed that giant underwater avalanches of sediment can transport these tiny particles along deep-sea canyons to greater depths.

We’ve now discovered how a global network of deep-sea currents transports microplastics, creating plastic hotspots within vast sediment drifts. By catching a ride on these currents, microplastics may be accumulating where deep-sea life is abundant.

Once plastic debris has broken down and sinks to the ocean floor, currents sweep the particles into vast drifts. Ian Kane, Author provided

From bedroom floors to the seafloor

We surveyed an area of the Mediterranean off the western coast of Italy, known as the Tyrrhenian Sea, and studied the bottom currents that flow near the seafloor. These currents are driven by differences in water salinity and temperature as part of a system of ocean circulation that spans the globe. Seafloor drifts of sediment can be many kilometres across and hundreds of metres high, forming where these currents lose their strength.

We analyzed sediment samples from the seafloor taken at depths of several hundred metres. To avoid disturbing the surface layer of sediment, we used samples taken with box-cores, which are like big cookie cutters. In the laboratory, we separated microplastics from the sediment and counted them under microscopes, analyzing them using infra-red spectroscopy to find out what kinds of plastic polymer types were there.

A microplastic fibre seen under a microscope. Ian Kane, Author provided

Most microplastics found on the seafloor are fibres from clothes and textiles. These are particularly insidious, as they can be eaten and absorbed by organisms. Although microplastics on their own are often non-toxic, studies show the build-up of toxins on their surfaces can harm organisms if ingested.

These deep ocean currents also carry oxygenated water and nutrients, meaning that the seafloor hotspots where microplastics accumulate may also be home to important ecosystems such as deep-sea coral reefs that have evolved to depend on these flows but are now receiving huge quantities of microplastics instead.

What was once a hidden problem has now been uncovered – natural currents and the flow of plastic waste into the ocean are turning parts of the seafloor into repositories for microplastics. The cheap plastic goods we take for granted eventually end up somewhere. The clothes that may only last weeks in your wardrobe linger for decades to centuries on the seafloor, potentially harming the unique and poorly understood creatures that live there.The Conversation

This article is republished from The Conversation by Ian Kane, Reader in Geology, University of Manchester and Michael Clare, Principal Researcher in Marine Geoscience, National Oceanography Centre under a Creative Commons license. Read the original article.

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B.C.'s "living dinosaurs" threatened by ocean warming and acidification – Straight.com

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The world’s warming oceans and the ongoing acidification of seawater are having a serious effect on B.C.’s rare glass sponges and their associated reefs, according to a study conducted by UBC researchers.

The sponge reefs—constructed by living glass sponges growing on the skeletons of previous generations—can grow to the height of a six-storey building and were thought to have become extinct worldwide about 40 million years ago, until the discovery of  massive reefs 200 metres deep in Hecate Strait in northern B.C. in 1987 (although they had been observed as unexplained “mounds” on the floors of Queen Charlotte Sound and Hecate Strait during sonar surveys a few years previous).

At the time, the reefs were described by astonished scientists as “living dinosaurs”. German paleontologist Manfred Krautter was quoted as saying their discovery in B.C. waters “electrified” him and was “like discovering a herd of dinosaurs on land”, and the prehistoric constructs are often referred to as “Jurassic Park submerged”.

Subsequent dives by scientists in submersibles determined that they were up to 6,000 years old and covered a surface area of up to 700 square kilometres. It is theorized that the sponges, which are living marine animals, started building reefs there after B.C.’s most recent glaciation period scraped the ocean bottom clean more than 9,000 years ago.

Since the first discoveries, another 19 glass-sponge reefs have been found in the Strait of Georgia, part of what is often called the Salish Sea. An American geologist found other, specialized, reefs off the coast of Washington state in 2007.

The sponges use dissolved silica—glass, essentially—to build skeletons constructed of needlelike so-called spicules. Although glass sponges are common around the world, only in very rare cases do they form reefs, building new structures on top of the skeletons of dead sponges. The relatively accessible reefs found in Howe Sound are unique in the world for their shallow depth of less than 40 metres.

The UBC paper—published on May 18 in Scientific Reports, an open-access, peer-reviewed journal—detailed the results of an experiment initiated by Angela Stevenson, a postdoctoral fellow at UBC’s zoology department who is the study’s lead researcher. Stevenson was aided by scientists from Fisheries and Oceans Canada’s Pacific Biological Station in Nanaimo, Vancouver’s Ocean Wise Research Institute, and UBC’s department of botany.

Stevenson brought some examples of Aphrocallistes vastus—called the cloud sponge and one of three species of reef-building glass sponges found in B.C. waters—from Howe Sound to a UBC lab. Water temperature and acidity were then manipulated for a four-month study, resulting in the first successful long-term lab experiment involving living glass sponges.

““Their sheer size and tremendous filtration capacity put them at the heart of a lush and productive underwater system, so we wanted to examine how climate change might impact their survival,” Stevenson said in a June 1 UBC news release.

The researchers were monitoring the sponges’ durability, pumping ability, and skeletal strength. The results showed that the sponges experienced up to a 25 percent loss in tissue and a 50-percent reduction in pumpong capacity. Their bodies also became more elastic and lost about half their strength.

“Most worryingly, pumping began to slow within two weeks of exposure to elevated temperatures,” Stevenson noted.

Glass-sponge reefs are home to many marine creatures in B.C., including fish and giant Pacific octopuses.
Diane Reid/Ocen Wise

Glass sponges survive by pumping enormous volumes of water through their systems, filtering out the bacteria and plankton that they eat and purifying the surrounding seawater. It is estimated that the 19 reefs that are known to be in the Salish Sea can filter up to 100 billion litres of seawater every day, removing about 80 percent of the particles and microbes therein.

The Canadian Parks and Wilderness Society’s (CPAWS) B.C chapter, which advocates to protect glass-sponge reefs, says that 95 percent of seawater bacteria are filtered out by glass sponges and that a small reef of the sponges will filter and clean a volume of water every 60 seconds that would fill an Olympic-sized swimming pool.

Diver Glen Dennison above a Howe Sound glass-sponge reef.
Adam Taylor/Marine Life Sanctuaries Society

The reefs are protected by various conservation efforts in B.C’s deep northern waters and shallower Salish Sea depths, including federal marine protected areas in Hecate Strait and Queen Charlotte Sound and smaller buffer zones in Howe Sound and the Strait of Georgia. CPAWS says that research shows both measuers require expansion to fully protect the delicate structures from potential fishing and resource-exploration damage.

Borttom fishing, especially trawling, can devastate glass-sponge reefs, and suspended sediment can choke the sponges’ feeding filters and even kill them. Crab and prawn traps can damage or crush the sponge skeletons.

Jeff Marliave, an Ocean Wise senior researcher and paper coauthor, said in the release that more study is needed to understand how climate change might affect the reefs. “In Howe Sound, we want to figure out a way to track changes in sponge growth, size and area and area in the field so we can better understand potential climate implications at a larger scale. We also want to understand the microbial food webs that support sponges and how they might be influenced by climate cycles.”

Stevenson had a cautionary thought about what is required to guarantee the future safety of the reefs, whaich have been described as “international treasures”.

“When most people think about reefs, they think of tropical shallow-water reefs like the beautiful Great Barrier Reef in Australia,” Stevenson said. “But we have these incredible deep-water reefs in our own backyard in Canada. If we don’t do our best to stand up for them, it will be like discovering a herd of dinosaurs and then immediately dropping dynamite on them.”

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What a dinosaur's last supper reveals about life in the Cretaceous period – CBC.ca

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A beautifully preserved armoured dinosaur found in an Alberta oilsands mine died on a full stomach. The “extraordinarily rare” preservation of its last meal offers new clues and surprises about how the dinosaur lived during its last days.

The 5.5-metre-long, 1,300 kilogram spiky, plant-eating nodosaur, similar to an ankylosaurus but without a tail club, is the only known one of its species, Borealopelta markmitchelli. (Its name means “shield of the north” and honours Mark Mitchell, the technician who spent 7,000 carefully extracting the fossil from the surrounding rock). 

Victoria Arbour, an evolutionary paleontologist at the Royal BC Museum, describes how some armoured dinosaurs likely used their horns, spines and armour for fighting each other, not just for protection. 1:34

The nodosaur lived 110 million years ago during the early Cretaceous, in a lush forest of conifers, ferns and palm-like plants called cycads, near the coast of what was then an inland sea. At the time, the climate was warmer, similar to that of South Carolina, said Caleb Brown, a paleontologist at the Royal Tyrrell Museum of Paleontology in Alberta and lead author of the new study. It was published this week in the journal Royal Society Open Science.

The fossil was discovered by accident in 2011 by Shawn Funk, a shovel operator at the Suncor Millennium Mine near Fort McMurray. Paleontologists from the Royal Tyrrell were called to have a look and realized at once that it was no ordinary fossil.

While most fossils include only bones, this one included skin. It was so well-preserved that it has been described as “mummified.”

Meet one of the world’s best-preserved dinosaurs ever. Borealopelta fossilized so perfectly that we can see every inch of its armour and skin in 3D, 110 million years after its death. 0:58

In the dinosaur’s belly, “there were these massive concentrations of what looked like rocks,” Brown said.

Those were in a mass about the size of a soccer ball, and it appears they were gastroliths — rocks that some plant-eating dinosaurs use to grind up their food in their stomachs, as modern birds do, instead of using their teeth.

Sure enough, when chunks of the mass were encased in resin, sliced and examined under the microscope, the researcher could see well-preserved twigs, leaves, mosses, pollen and spores.

To get some help at identifying the plant material, the dinosaur researchers turned to paleobotanists, including University of Brandon researcher David Greenwood and his team, along with their retired Royal Tyrrell colleague Dennis Braman.

Inside the nodosaur’s belly was a mass about the size of a soccer ball that contained rocks. The rocks are called gastroliths and are used to grind up the animal’s food within its stomach. (Royal Tyrrell Museum)

Ferns and charcoal

They discovered that the dinosaur was a bit of a picky eater. While it lumbered through a landscape that was lush with conifers, horsetails and cycads, there weren’t a lot of those in its stomach.

“It’s almost all ferns,” Brown said, noting that ferns aren’t actually very nutritious. “It wasn’t just hoovering up everything on the landscape.”

But to him, the biggest surprise was that the stomach also contained a significant amount of wood, mostly charcoal, suggesting it was feeding in an area that had recently been ravaged by wildfires.

“And that’s a really cool result,” Brown said. “Because if you look at large mammals that are herbivores today, they often seek out areas that are recovering from forest fires.”

That’s because the new growth tends to be lush, more nutritious than older plants, and low to the ground where it’s easily accessible.

Microscope images show some of the plant material found inside the stomach, including a club moss spore sac (a), fern spore sacs (b-d), a charcoal fragment (e), parts of plant stems and leaves (f-l) and a cross section of a twig, showing its annual rings (m). (Brown et al/Royal Tyrrell Museum)

Forensic paleobotany

By looking at the types of spores and the fact that the twigs appeared to be in the middle of their growing season, the researchers figured out that the animal died during the wet season, which was late spring or early summer.

In Dinosaur Cold Case, a recent documentary about the fossil on CBC’s Nature of Things, Greenwood said extreme storms and flash floods would have been a problem at that time of year on the coastal plain where the dinosaur and suggested that being swept away by rushing water may have been what caused its death.

These are some plant fossils from Alberta from about the time that Borealopelta lived, including ferns, a gingko (d), horsetails (i) and a conifer cone (j). (Brown et al/Royal Tyrrell Museum)

The discoveries about the nodosaur’s last meal are significant because to date, Brown said, “we know almost nothing about what herbivorous dinosaurs eat.”

Only guesses can be made based on what plants lived nearby and the dinosaur’s teeth. There are also clues in fossil dinosaur feces, but the plant material in those are often digested beyond recognition and it’s difficult to know which dinosaur they came from.

Part of the problem is that finding preserved stomach contents from a dinosaur is “extraordinarily rare,” Jim Basinger of the University of Saskatchewan, a co-author of the study, said in a statement. 

Nine cases of possible dinosaur stomachs of plant-eating dinosaurs have been found, the researchers note, but most have turned out to just be plant material found nearby rather than actual stomachs. In this case, the dinosaur was washed far out to sea, without any plants from the landscape it lived in, before it was fossilized.

“So in this case we have what I would say is by far the best evidence that these are stomach contents,” Brown said.

That said, he notes that it may not necessarily be representative of what this species normally ate, as an animal’s diet can vary depending on its age, its health, and the seasonal availability of different foods.

Still, he said it’s useful to be able to compare it to what scientists think plant-eating dinosaurs were eating at that time and raises new questions to investigate, such as: How much of this food a dinosaur this size would have needed to eat to sustain itself? And how did it digest it?

 “I think give us a benchmark for figuring out how this animal may have lived.”

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‘Strawberry Moon’ to rise with a special eclipse for some skywatchers – Globalnews.ca

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The full moon on Friday, June 5 might look a little different in some parts of the world, where the so-called “Strawberry Moon” will fall partially under the Earth’s shadow.

The phenomenon, known as a penumbral lunar eclipse, occurs when the Earth comes between the sun and the moon, thereby casting a faint shadow on the moon. This penumbral lunar eclipse will make the full moon look slightly darker on part of its surface, although only some portions of the world will see it.

The penumbral lunar eclipse will only be visible from parts of Australia, Asia, Africa, Europe and South America, according to NASA’s charts.


READ MORE:
Pentagon officially releases three leaked ‘UFO’ videos

In other words, North Americans will need to watch a livestream on the internet to catch a glimpse of the event, which starts at 3 p.m. EDT. Nevertheless, the so-called “Strawberry Moon” will be visible to everyone.

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That name comes from the time of year and not the expected colour of the moon. There are farm-related nicknames for the first full moon of every month, and the strawberry nickname originated from the Algonquin First Nation, according to the Old Farmer’s Almanac. The first full moon of June often coincided with the harvest season for wild strawberries in North America, the Almanac says.


The Strawberry Moon is practically full over the horizon as a lady poses for a photo in Malaga, Spain, on June 4, 2020.


Jesus Merida/SOPA Images/LightRocket via Getty Images

Although skywatchers in Canada and the U.S. will miss out on this penumbral lunar eclipse, they’ll only have to wait a month to catch the next one. Another penumbral lunar eclipse is slated to happen on July 5, and that one should be visible from North America. The darkest penumbral lunar eclipse of the year is expected on Nov. 30.

A penumbral lunar eclipse also happened on Jan. 10, coinciding with that month’s “Wolf Moon.”

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Timelapse captures moment sky darkens for total solar eclipse


Timelapse captures moment sky darkens for total solar eclipse

Not to throw shade at the penumbral lunar eclipses, but they’ll likely pale in comparison to the annular solar eclipse predicted for June 21. That’s when the moon will pass between the Earth and the sun, making the sun look like a ring of fire for viewers in parts of Africa, China, northern India and Pakistan, according to TimeandDate.com.

Again, it won’t be visible from North America — but you’ll still be able to watch the whole thing online without risking eye damage from staring at the sun.

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© 2020 Global News, a division of Corus Entertainment Inc.

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