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Gold mining stunts Amazon rainforest recovery

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June 29 (UPI) — The effects of gold mining on forest health are long lasting. According to new research, gold mining stunts the regrowth of Amazon forests, limiting their ability to store carbon.

“Historically gold mining was often overlooked in deforestation analysis as it occupies relatively small areas when compared to pastures or large-scale agriculture,” lead study author Michelle Kalamandeen told UPI in an email.

Kalamandeen started the research as a postgraduate researcher at the University of Leeds but is now a postdoctoral researcher at Cambridge University.

“Yet, given recent proliferation in mining activities since 2007-2008 and again in 2012, the potential areas may be underestimated and the impact on biodiversity and forest recovery unquantified,” she said.

For the study, Kalamandeen and her colleagues sampled soil and measured trees at 18 test plots in two main gold mining areas in Guyana. Researchers also established two control sites in old-growth forests.

“We measured trees/saplings/seedlings within each plot and took soil samples from abandoned gold mining sites, active sites and control ‘old-growth’ sites,” Kalamandeen said.

The data — published Monday in the Journal of Applied Ecology — showed trees in forests damaged by gold mining activity struggled to reestablish themselves. Where as forest harmed by other kinds of activities, such as logging and agriculture, were able to rebound, the negative effects of mining on growth and carbon storage persisted.

“Our analysis showed that the lack of nitrogen was the primary driving force for the lack of recovery occurring on the tailing ponds and mining pits,” Kalamandeen said. “On the overburden, where there was an abundance of nitrogen, regrowth of trees were similar to other Neotropical secondary, recovery forests.”

Researchers were surprised to find that a lack of nitrogen, instead of an excess of mercury, was to blame for the stunted regrowth.

“Our research showed that active mines had on average 250 times more mercury than abandoned mining sites, suggesting that this mercury leaches into neighboring forests and rivers,” Kalamandeen said.

Researchers found that in the few mining sites where topsoil was replaced and fertilized with nitrogen — an often mandated, but rarely enforced, restoration step — regrowth was comparable to plots where trees were cleared for other types of activity.

Scientists hope their findings will inspire politicians and policy makers in the Amazon to strengthen environmental regulations for gold mining.

“It’s important the current environmental policies are enforced. Most Amazonian countries have reasonable monitoring and enforcement policies but weakening of such policies or reduced funding to regulatory agencies as we’ve seen in Brazil and Venezuela, means that enforcement isn’t occurring,” Kalamandeen said.

“Addressing corruption in mining agencies is also another issue that needs addressing at the national scale,” Kalamandeen said. “For restoration, many Amazonian countries don’t have a forest restoration policy when it comes to gold mining and this needs to be tested and developed for tropical forests at the landscape-scale.”

Gold prices often rise in the wake of economic crises, and when they do, small-scale gold mining activity ramps up in the Amazon.

Though under new leadership, Brazil has recently been weakening environmental regulations. But in the years that followed the financial crisis, strong rainforest protections forced miners to pursue gold in neighboring countries, especially the dense forests of Guyana and the French Guiana.

With the COVID-19 pandemic putting a significant dent in global economic growth, researchers worry gold mining activity will once again proliferate across a large stretch of forest known as the Guiana Shield. In the future, scientists hope to test new technologies designed to curb the threat of gold mining.

“We hope to use remote sensing to help detect gold mining especially illegal mining within the Amazon,” Kalamandeen said.



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NASA’s OSIRIS-REx touches down on asteroid Bennu to nab sample

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Oct. 20 (UPI) — NASA’s OSIRIS-REx touched down on asteroid Bennu on Tuesday evening in a mission to scoop a sample of rocks and dirt.

The spacecraft — the Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer — made soft contact with the asteroid at 6:12 p.m. EDT.

The historic “touch and go” event featured animation displaying OSIRIS-REx’s sample collection activities in real time. It takes time for real images of the touchdown to travel back to the Earth, so they won’t be released to the public until Wednesday.

The craft executed a series of maneuvers over the course of several hours before making soft contact with the surface of the asteroid to collect regolith, or rocks and dirt.

“It will be four and a half hours of anxiousness,” Beth Buck, OSIRIS-REx mission operations manager at Lockheed Martin Space, said in a news conference ahead of the event.

Buck made a comparison to the descent of a spacecraft on Mars, when there is typically “seven minutes of terror.”

The goal is to learn more about the solar system’s history and help “planetary defense” engineers with missions to protect earth from rogue asteroids. Bennu is believed to be a window into the solar system’s past since it’s a pristine, carbon-rich body carrying building blocks of both planets and life.

At around 1:50 p.m. EDT, the spacecraft left orbit around the asteroid before executing a series of burns to position itself over a sampling area nicknamed Nightingale.

Once in position, the craft began its approach to the asteroid at 5:50 p.m. EDT. It then spent about 15 seconds attempting to collect the regolith sample before backing away again.

The area, which is 52 feet in diameter, will make for a more demanding landing than expected, Kenneth Getzandanner, OSIRIS-REx flight dynamics manager at the NASA Goddard Space Flight Center in Maryland, said in the news conference.

The original mission called for a landing “zone” about 150% larger than Nightingale, at 82 feet, but that changed because Bennu was more rocky than expected.

The goal was to collect at least 1.7 ounces of fine-grained material, but the spacecraft can carry up to 4.4 pounds, Heather Enos, OSIRIS-REx deputy principal investigator at the University of Arizona said.

“I would love for that capsule to be completely full,” Enos said.

Though early images from the asteroid should hint at whether the mission succeeded, it will take engineers roughly 10 days to compare and analyze the mass before and after the maneuver to actually know how much dirt is inside the OSIRIS-REx.

If it failed, the spacecraft has enough fuel to attempt two more touch downs to collect material.

The spacecraft is expected to return to Earth, with the regolith sample from Bennu, in 2023.



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SpaceX scrubs Starlink launch until Thursday, if weather cooperates

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Oct. 21 (UPI) — Just three days after sending 60 more Starlink satellites into orbit, SpaceX is aiming to launch another batch of broadband satellites into space from Florida.

If the weather cooperates, Thursday’s launch will be SpaceX’s 15th Starlink mission.

Liftoff had been scheduled for 12:29 p.m. EDT Wednesday aboard a Falcon 9 rocket at Launch Complex 40 at Cape Canaveral Air Force Station, but controllers scrubbed the launch due to weather and rescheduled for 12:14 p.m. on Thursday.

With a launch Sunday, SpaceX increased the size of their Starlink constellation to nearly 800 satellites. The 15th mission will see another 60-odd satellites join the network.

“The goal of Starlink is to create a network that will help provide Internet services to those who are not yet connected, and to provide reliable and affordable Internet across the globe,” according to the Kennedy Space Center.

Weather for Wednesday’s planned launch had looked so-so and the Space Force’s 45th Weather Squadron predicted a 60 percent chance of favorable conditions.

“A mid-level inverted trough and associated easterly wave currently across the Bahamas will meander into the state over the next few days, bringing enhanced moisture, cloud cover, and instability with a higher coverage of showers and storms,” Space Force forecasters wrote.

They said Thursday’s forecast looks quite similar to Wednesday’s.

Earlier this month, SpaceX founder and CEO Elon Musk tweeted that Starlink’s constellation was big enough to begin beta-testing the Internet service system in both the United States and southern Canada.

SpaceX has already offered Starlink Internet services to emergency responders in wildfire-stricken areas of Washington State.

Washington’s Hoh tribe is also using the Internet service to provide their members online education and telehealth services.



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Chernobyl-level radiation harms bumblebee reproduction

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Oct. 21 (UPI) — Bees are more sensitive to radiation than scientists thought. Scientists found the reproduction rates of bumblebees declined significantly when exposed to Chernobyl-level radiation.

The research, published Wednesday in the journal Proceedings of the Royal Society B: Biological Sciences, suggests radiation in Ukraine’s Chernobyl Exclusion Zone could impair pollination services, triggering wider ecological consequences than previously estimated.

Humans are not allowed to live in the Chernobyl Exclusion Zone, the disaster area more directly impacted by the 1986 nuclear accident, the worst in history. However, the destroyed nuclear reactors are surrounded by forests that are populated by robust populations of birds, bears, bison, lynx, moose, wolves and more.

Efforts to gauge the effects of radiation contamination on insects have yielded mixed results in the past. While some studies have suggested insects are relatively radiation-resistant, others have demonstrated significant impairment.

When researchers exposed bumblebees in the lab to radiation dose of 100 µGyh-1, an amount approximating exposure inside the Chernobyl Exclusion Zone, reproduction rates among the bees dropped between 30 and 45 percent.

Researchers found a direct correlation between the size of the radiation dose and reproduction rate declines. Lower levels of radiation had a smaller effect, while larger doses yielded greater declines.

Scientists were surprised to find they were able to detect reproductive rate declines at very small levels of radiation exposure.

“Our research provides much needed understanding as to the effects of radiation in highly contaminated areas and this is the first research to underpin the international recommendation for the effects of radiation on bees,” lead study author Katherine Raines, environmental scientist at the University of Stirling in Scotland, said in a news release.



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