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The power of earthworm poop and how it could influence climate change – CBC.ca

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There is a confounding mystery wrapped up in the tiny turds of two different types of earthworms, and the secrets locked inside are influencing climate change around the world.

Scientists say some earthworm species are potentially speeding up climate change by feeding on leaves, then pooping out a mix that’s fodder to tiny microbes and fungi that spew carbon into the atmosphere. By contrast, other worms are helping lock carbon in soil.

Canada is ground zero for this paradox. Earthworm populations are growing as warmer temperatures allow the invertebrates to move farther north than ever before.

And no one knows exactly how much carbon they are helping release into the atmosphere.

“Some of the early work has shown that they could have as much of an impact as, let’s say, wildfire,” said Sylvie Quideau, a professor of soil biogeochemistry at the University of Alberta.

It’s possible, she said, worms in Canada could release millions of tonnes of carbon into the atmosphere in a year, but that estimate is still subject to a lot of uncertainties, including the rate of earthworm invasion across the country.

Sylvie Quideau, a professor of soil biogeochemistry at the University of Alberta, says early work on earthworms show ‘they could have as much of an impact as, let’s say, wildfire.’ (Submitted by Sylvie Quideau)

The most common earthworms that live in leaf litter, on forest floors or in the top layers of soil are called Dendrobaena octaedra. They eat plant debris, and their poop, also known as casts, is more easily broken down by microbes and fungi that then release carbon dioxide.

“Microbes find earthworm poop very attractive,” said Quideau.

The more earthworms there are, the more plant debris is broken down at a faster rate and the more carbon gets released into the atmosphere.

This kind of carbon being released from Canada’s boreal forests is new, according to Quideau, since earthworms are not native to the country. They were wiped out during the last ice age.

The earthworms here now, save for some found in British Columbia, are invasive species transported into forests when Europeans arrived or brought them in from the United States as fishing bait.

“Earthworms can both be allies and enemies,” said Joann Whalen, a professor in the department of natural resource sciences at Montreal’s McGill University who has studied earthworms for 20 years. 

In agriculture, earthworms are beneficial, said Whalen: They help make soil more fertile, and allow water and roots to more easily enter the ground. 

In spring, it is common to see spherical lumps of earth on the soil surface. These earthworm casts are a mixture of soil and organic residues that all earthworm species poop out or egest onto the soil surface. The white object is a toonie, to give an idea of the cast size. (Submitted by Joann Whalen)

In the boreal forest, worms can do more harm than good. 

Some eat the leaf litter covering the forest floor, and many plant seeds need that thick covering to grow in. Without it, the seeds can’t take root, said Whalen, which means earthworms can reduce plant diversity in the forest.

But earthworms aren’t all bad. There are some burrowing species that actually trap carbon in the soil, because their poop binds it more tightly and makes it harder for microbes to break down.

Often sold as fishing bait, Lumbricus terrestris is a common deep-burrowing earthworm found in Canada. It can be identified by the small mounds of earth it leaves on lawns or in forests.

How much carbon is being trapped by these worms and whether it’s enough to offset the carbon other worms are helping release isn’t clear. Finding the answer to that question is part of Quideau’s research.

“What keeps me up at night is wondering if I can quantify their effect on climate change,” she said.

‘Earthworms can both be allies and enemies,’ says Joann Whalen, a professor in the department of natural resource sciences at Montreal’s McGill University. (Submitted by Joann Whalen)

Whalen isn’t losing any sleep over worms. She said the carbon dioxide coming from decomposing plant material is a natural process, and worms help it.

“I’d be more concerned about what people are doing in terms of utilizing fossil carbon that had been buried for millennia and is now being released into the atmosphere.”

Still, in Canada, the earthworm invasion continues.

Erin Cameron, an assistant professor in the department of environmental science at Saint Mary’s University in Halifax, has been monitoring the invasion’s progress since 2006. 

In northern Alberta, she’s been studying how fast earthworms are spreading, and has discovered they are moving north at a rate of 17 metres a year. The earthworm population appears to have grown as well.

Dendrobaena octaedra is one of the most common earthworms that live in the leaf litter on the forest floor or in the top layers of soil. (Submitted by Erin Cameron)

The most abundant kind of earthworm she finds live in leaf litter or in the top layers of soil, the ones that help release carbon into the air.

“Earthworms may benefit from warmer temperatures in Canada’s North, for example, because that may currently be restricting the distributions of some species,” said Cameron.

So as climate change continues to warm the country, earthworms could continue to become more abundant and possibly drive more climate change.

Erin Cameron, an assistant professor in the department of environmental science at Saint Mary’s University, has been monitoring the earthworm invasion’s progress since 2006. (Submitted by Erin Cameron)

Quideau doesn’t think there’s anything that can be done to stop the worm march through Canada.

“What’s important is that we can understand, quantify their effect better so that we can project better in the future what their influence will be. There might be ways then to manage a forest.”

She and other researchers hope to do just that in the next few years. They want to crack the secret of earthworm poop, and determine how much carbon earthworms release and store in the earth.

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VIDEO: Why Nova Scotia health officials are testing for COVID-19 in a community that's largely been spared from the virus – TheChronicleHerald.ca

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Over the weekend of Jan. 16-17, people in the Bridgewater, N.S. area were offered rapid COVID-19 testing for the first time since the province introduced the process last fall.

In the video above, Dr. John Ross speaks to SaltWire’s Sheldon MacLeod about why Nova Scotia health officials are looking for the virus in a community that has been mostly free of infections, even during the height of the outbreaks in the province.

This weekend, people in the Bridgewater area were offered Rapid COVID-19 testing for the first time since the province introduced the process last fall. Dr. John Ross explains why are they looking for the virus in a community that has been mostly free of infections, even during the height of the outbreaks in Nova Scotia. - Sheldon MacLeod
This weekend, people in the Bridgewater area were offered Rapid COVID-19 testing for the first time since the province introduced the process last fall. Dr. John Ross explains why are they looking for the virus in a community that has been mostly free of infections, even during the height of the outbreaks in Nova Scotia. – Sheldon MacLeod
- Sheldon MacLeod
– Sheldon MacLeod
- Sheldon MacLeod
– Sheldon MacLeod

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A 'super-puff' planet like no other – Nanowerk

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Jan 18, 2021 (Nanowerk News) The core mass of the giant exoplanet WASP-107b is much lower than what was thought necessary to build up the immense gas envelope surrounding giant planets like Jupiter and Saturn, according to a Canadian-led team of astronomers, including McGill University Professor Eve Lee. This intriguing discovery by Caroline Piaulet of the Université de Montréal under the supervision of Björn Benneke suggests that gas-giant planets form a lot more easily than previously believed. Published in Astronomical Journal (“WASP-107b’s Density Is Even Lower: A Case Study for the Physics of Planetary Gas Envelope Accretion and Orbital Migration”) by a team of astronomers from Canada, the U.S., Germany and Japan, the new analysis of WASP-107b’s internal structure has big implications. “This study pushes the boundaries of our theoretical understanding of how giant-sized planets form. WASP-107b is one of the puffiest planets out there, and we need a creative solution to explain how these tiny cores can build such massive gas envelopes,” says co-author Eve Lee, Assistant Professor in the Department of Physics at McGill University and McGill Space Institute.

As big as Jupiter but 10 times lighter

WASP-107b was first detected in 2017 around WASP-107, a star about 212 light years from Earth in the Virgo constellation. The planet is very close to its star — over 16 times closer than the Earth is to the Sun. About as big as Jupiter but 10 times lighter, WASP-107b is one of the least dense exoplanets known: a type astrophysicists have dubbed “super-puffs” or “cotton-candy” planets. The astronomers first used observations of WASP-107 obtained at the Keck Observatory in Hawaii to assess the planet’s mass more accurately. They used the radial velocity method, which allows scientists to determine a planet’s mass by observing the wobbling motion of its host star due to the planet’s gravitational pull. They concluded that the mass of WASP-107b is about one tenth that of Jupiter, or about 30 times that of Earth. In analyzing the planet’s most likely internal structure, they came to a surprising conclusion: with such a low density, the planet must have a solid core of no more than four times the mass of the Earth. This means that more than 85 percent of its mass is included in the thick layer of gas that surrounds this core. In comparison, Neptune, which has a similar mass to WASP-107b, only has 5 to 15 percent of its total mass in its gas layer.

A gas giant in the making

Planets form in the disc of dust and gas that surrounds a young star called a protoplanetary disc. Classical models of gas-giant planet formation are based on Jupiter and Saturn. In these, a solid core at least 10 times more massive than the Earth is needed to accumulate a large amount of gas before the disc dissipates. Without a massive core, gas-giant planets were not thought able to cross the critical threshold necessary to build up and retain their large gas envelopes. How then do we explain the existence of WASP-107b, which has a much less massive core? Professor Lee, who is a world-renowned expert on super-puff planets like WASP-107b, has several hypotheses. “For WASP-107b, the most plausible scenario is that the planet formed far away from the star, where the gas in the disc is cold enough that gas accretion can occur very quickly,” she said. “The planet was later able to migrate to its current position, either through interactions with the disc or with other planets in the system,” she says.

Discovery of a second planet

The Keck observations of the WASP-107 system cover a much longer period of time than previous studies have, allowing the research team to make an additional discovery: the existence of a second planet, WASP-107c, with a mass of about one-third that of Jupiter, considerably more than WASP-107b’s. WASP-107c is also much farther from the central star; it takes three years to complete one orbit around it, compared to only 5.7 days for WASP-107b. Also interesting: the eccentricity of this second planet is high, meaning its trajectory around its star is more oval than circular. “WASP-107c has in some respects kept the memory of what happened in its system,” said Piaulet. “Its great eccentricity hints at a rather chaotic past, with interactions between the planets which could have led to significant displacements, like the one suspected for WASP-107b.” The researchers plan to continue studying WASP-107b, hopefully with the James Webb Space Telescope set to launch in 2021, which will provide a much more precise idea of the composition of the planet’s atmosphere.

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Pool closures a bitter pill for people with disabilities – CBC.ca

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Mary Jane Clinkard suffers from a neuromuscular disability that requires her to exercise to maintain her strength, but with municipal pools under lockdown since Boxing Day, she hasn’t been able to do that.

Now her muscles feel weak, stiff and painful, and her independence is in jeopardy. The 50-year-old fears she’ll need a personal support worker to get in and out of her wheelchair if she can’t get back into the water soon.

Clinkard, who has hypotonia, told CBC’s Ottawa Morning it’s especially disheartening when she hears others talking about the activities they’re able to do during the lockdown.

“I get really, really frustrated when I hear, ‘We all go skating or go skiing,’ and I’m like, ‘Well, I can’t do either of those,'” Clinkard said.

Once the pools reopened in July, it took Clinkard months of swimming three times a week to get back into shape. Then Ontario entered another lockdown.

The Sandy Hill woman would like to see swimming pools deemed essential, and said she’s not the only one who depends on them for her health.

“There are other people who cannot walk, who cannot ski, cannot skate,” she said.

Mary Jane Clinkard, 50, suffers from hypotonia, and says she’s not the only one who depends on swimming to stay healthy. (Submitted by Mary Jane Clinkard)

No exemptions

According to Dan Chenier, the city’s general manager of recreation, cultural and facility services, the provincial restrictions currently in place don’t allow exemptions for people wishing to use indoor municipal facilities for physical therapy or rehabilitation.

“Provincial authorities have been made aware of the request for an exemption for […] these services and the City will be monitoring the revised regulations for any changes,” Chenier said in an emailed statement. 

When am I going to be back in the water? When am I going to be able to swim again?– Mary Jane Clinkard

According to the office of Sylvia Jones, Ontario’s solicitor general, the second wave of COVID-19 poses a serious threat to the province’s most vulnerable. 

“The single most important thing Ontarians can do right now to protect our most vulnerable is to stay at home,” wrote Stephen Warner, Jones’s press secretary and issues manager. “As we continue our vaccine rollout, this is our best defense against this virus.”

According to Warner, municipalities don’t have the power to ease restrictions put in place under the province’s lockdown. 

Restrictions ‘frustrating and difficult’

Under the stay-at-home order, only “exercising, including walking or moving around outdoors using an assistive mobility device, or using an outdoor recreational amenity” are allowed. 

Coun. Matt Luloff, who represents Orléans and sits on the city’s community and protective services committee, called that lack of flexibility “frustrating and difficult.”

Ottawa Morning8:34Pool use for disabled people during lockdown

An Ottawa woman is hoping the province will reconsider its decision to close pools during lockdown so disabled people can use pools to maintain their muscle strength. Councillor Matthew Luloff weighs in on the province’s decision to close pools and whether any exceptions can be made. 8:34

On Monday, Luloff told Ottawa Morning if exemptions can be made for NHL players, then people who rely on certain facilities for their health and well-being should be granted similar leeway.

“We can say to one group of people that it’s fine to … bubble and to provide entertainment for us,” he told Ottawa Morning on Monday. “But when there’s a real need, a real physical [or] mental health need, that’s just not as important as getting to see the Sens play.”

“Maybe if the city doesn’t feel comfortable opening people pools for everybody, they can open one pool for people who really need it,” Clinkard suggested. “When am I going to be back in the water? When am I going to be able to swim again?”

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