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ScienceDaily

Gold mining restricts Amazon rainforest recovery

Gold mining significantly limits the regrowth of Amazon forests, greatly reducing their ability to accumulate carbon, according to a new study. The researchers warn that the impacts of mining on tropical forests are long-lasting and that active land management and restoration will be necessary to recover tropical forests on previously mined lands.

Gold mining has rapidly increased across the Amazon in recent years, especially along the Guiana Shield, where it is responsible for as much as 90% of total deforestation. The Shield encompasses Guyana, Suriname, French Guiana, Venezuela and small parts of Colombia and northern Brazil, and its forests hold roughly twenty billion tonnes of aboveground carbon in its trees.

The ability of tropical forests to recover from gold mining activities has remained largely unquantified. Now, an international study led by the University of Leeds is the first to provide detailed field-based information on the regeneration of forests in Guyana after gold mining, and the first ground-based estimate of carbon sink lost as a result of gold mining activities across the Amazon.

The team’s findings, published in the Journal of Applied Ecology, found that forest recovery rates on abandoned mining pits and tailing ponds are amongst the lowest ever recorded for tropical forests. At some sites there was nearly no tree regeneration even after three to four years since mining had stopped.

They estimate that mining-related deforestation results in the annual loss of over two million tons of forest carbon across the Amazon. The lack of forest regrowth observed following mining suggests that this lost carbon cannot be recovered through natural regeneration.

Lead author Dr Michelle Kalamandeen, began this research as a postgraduate researcher in the School of Geography at Leeds she is now a postdoctoral researcher at Cambridge University. She said: “This study shows that tropical forests are strongly impacted by mining activities, and have very little capacity to re-establish themselves following mining.

“Our results clearly show the extraction process has stripped nitrogen from the soil, a critical component to forest recovery, and in many cases directly contributed to the presence of mercury within neighbouring forests and rivers. Active mining sites had on average 250 times more mercury concentrations than abandoned sites.

“Not only does this have serious consequences for our battle against global warming by limiting Amazonian forests’ ability to capture and store carbon, but there is also a larger implication of contaminating food sources especially for indigenous and local communities who rely on rivers.

“A positive finding from this study shows that overburden sites, areas where topsoil is deposited during the mining process, recorded similar recovery rates as other Central and South American secondary tropical forests abandoned after agriculture or pasture.

“Active management and enforcement of laws is clearly needed to ensure recovery and to safeguard communities and there are methods available, such as replacing the soil using the overburdens at abandoned sites. But there is an urgent need for large-scale recovery management to be tested and implemented.

“We could be facing a race against the clock. The current crisis is significantly increasing the demand for gold, given its perceived role as an economic stabiliser. With current gold price more than US$1700 per ounce and estimated to reach US$2000-3000 in the coming months, many artisanal and small-scale miners are already rapidly responding to this increase in pricing, and the weakening of environmental laws and policies as we’ve seen in Brazil, leading to further deforestation in the Amazon.”

The team used forest inventory plots installed on recently abandoned mines in two major mining regions in Guyana, and re-censused the sites 18 months later. The study analysed soil samples and determined individual trees’ above-ground biomass — the tree’s living plant material — to determine recovery and chemical changes caused by mining.

Their results suggest that forest recovery is more strongly limited by severe mining-induced depletion of soil nutrients, especially nitrogen, rather than by mercury contamination. The high rate of mercury does however have serious implications for negative impacts on food security, water supply and local biodiversity.

Study co-author, Dr David Galbraith, Associate Professor in Earth System Dynamics at Leeds, said: “Currently approximately 1.3 million square kilometres of the Amazon is under prospecting for mining activities.

“This research provides support to local and national governance structures to critically approach policy implementation and development for land management, including how and where mining occurs, and more stringent monitoring and action for forest recovery. It shows that carefully planned active restoration projects will be critical in this regard.

“But responsibility lies beyond remediation efforts to mitigate the damage done. Investors and consumers alike need increased awareness and accountability of the environmental footprints of gold mining.”

The Guyana Geology and Mines Commission (GGMC) who supported the fieldwork are optimistic that the results from this research will help in making more informed decisions for their reclamation policies and programmes, monitoring and enforcement.

Mr Newell Dennison, Commissioner of the GGMC said: “The research results showed two important aspects: that overburden areas recovered relatively well and there was limited recovery in mining pits and tailing ponds. The latter being areas where we need improved management. The more data we can accumulate for recovery of secondary forests in mined out areas, the better we are all positioned for the implementation of effective programmes and operations that aid in the recovery of our rainforests. We look forward to working with Dr Kalamandeen and her team in the future.”

The Guyana Forestry Commission (GFC) expressed gratitude and appreciation to the research team for the important and impressive empirical work done in [this] paper.

Mr Gavin Agard, Commissioner of the GFC said: “We expect that this scientific work has greatly improved Guyana’s baseline and understanding of the forest degradation impacts of mining with respect to biomass recovery and sets a foundation for more dynamic, focused studies to advise planning and policy for improving secondary forest growth and restoring biomass capacity.

“The findings and recommendations from this study will significantly impact policy and management strategies for forest restoration and rehabilitation in mined-out areas, which is a key objective for Guyana under the Paris Agreement of the UNFCCC.

“The contribution of deforestation and degradation to climate change cannot be ignored, and thus we welcome the contributions of this research team to build and improve our communal knowledge and understanding of our changing forests as we continue to pursue the highest standards of sustainable forestry in Guyana.”

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3D Printing Industry

Stratasys to cut 10% of workforce in strategic resizing

3D printer manufacturer Stratasys has announced that it will be reducing its global workforce by 10% as part of its plan to operate on a “leaner” business model. Spurred on by the financial implications of the pandemic, the resizing aims to reduce operating costs and drive the company on a profitable growth trajectory.  Yoav Zeif, […]

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Grants.gov

Improving oral health and reducing disparities in adolescents (R01 Clinical Trial Not Allowed)

Funding Opportunity ID: 322582
Opportunity Number: PAR-20-058
Opportunity Title: Improving oral health and reducing disparities in adolescents (R01 Clinical Trial Not Allowed)
Opportunity Category: Discretionary
Opportunity Category Explanation:
Funding Instrument Type: Grant
Category of Funding Activity: Health
Category Explanation:
CFDA Number(s): 93.121
Eligible Applicants: State governments
County governments
City or township governments
Special district governments
Independent school districts
Public and State controlled institutions of higher education
Native American tribal governments (Federally recognized)
Public housing authorities/Indian housing authorities
Native American tribal organizations (other than Federally recognized tribal governments)
Nonprofits having a 501(c)(3) status with the IRS, other than institutions of higher education
Nonprofits that do not have a 501(c)(3) status with the IRS, other than institutions of higher education
Private institutions of higher education
For profit organizations other than small businesses
Small businesses
Others (see text field entitled “Additional Information on Eligibility” for clarification)
Additional Information on Eligibility: Other Eligible Applicants include the following: Alaska Native and Native Hawaiian Serving Institutions; Asian American Native American Pacific Islander Serving Institutions (AANAPISISs); Eligible Agencies of the Federal Government; Faith-based or Community-based Organizations; Hispanic-serving Institutions; Historically Black Colleges and Universities (HBCUs); Indian/Native American Tribal Governments (Other than Federally Recognized); Non-domestic (non-U.S.) Entities (Foreign Organizations); Regional Organizations; Tribally Controlled Colleges and Universities (TCCUs) ; U.S. Territory or Possession; Non-domestic (non-U.S.) Entities (Foreign Institutions) are not eligible to apply. Non-domestic (non-U.S.) components of U.S. Organizations are not eligible to apply. Foreign components, as defined in the NIH Grants Policy Statement, are allowed.
Agency Code: HHS-NIH11
Agency Name: Department of Health and Human Services
National Institutes of Health
Posted Date: Nov 18, 2019
Close Date: Jan 07, 2023
Last Updated Date: Nov 18, 2019
Award Ceiling: $0
Award Floor: $0
Estimated Total Program Funding:
Expected Number of Awards:
Description: The purpose of this Funding Opportunity Announcement (FOA) is to stimulate research to improve the oral health of adolescents in the United States, and to reduce observed oral health disparities and inequities in this population. This FOA defines adolescents as those individuals between the ages of 10 and 19.
Version: 1

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Grants.gov

Improving oral health and reducing disparities in adolescents (R21 Clinical Trial Not Allowed)

Funding Opportunity ID: 322583
Opportunity Number: PAR-20-059
Opportunity Title: Improving oral health and reducing disparities in adolescents (R21 Clinical Trial Not Allowed)
Opportunity Category: Discretionary
Opportunity Category Explanation:
Funding Instrument Type: Grant
Category of Funding Activity: Health
Category Explanation:
CFDA Number(s): 93.121
Eligible Applicants: State governments
County governments
City or township governments
Special district governments
Independent school districts
Public and State controlled institutions of higher education
Native American tribal governments (Federally recognized)
Public housing authorities/Indian housing authorities
Native American tribal organizations (other than Federally recognized tribal governments)
Nonprofits having a 501(c)(3) status with the IRS, other than institutions of higher education
Nonprofits that do not have a 501(c)(3) status with the IRS, other than institutions of higher education
Private institutions of higher education
For profit organizations other than small businesses
Small businesses
Others (see text field entitled “Additional Information on Eligibility” for clarification)
Additional Information on Eligibility: Other Eligible Applicants include the following: Alaska Native and Native Hawaiian Serving Institutions; Asian American Native American Pacific Islander Serving Institutions (AANAPISISs); Eligible Agencies of the Federal Government; Faith-based or Community-based Organizations; Hispanic-serving Institutions; Historically Black Colleges and Universities (HBCUs); Indian/Native American Tribal Governments (Other than Federally Recognized); Non-domestic (non-U.S.) Entities (Foreign Organizations); Regional Organizations; Tribally Controlled Colleges and Universities (TCCUs) ; U.S. Territory or Possession; Non-domestic (non-U.S.) Entities (Foreign Institutions) are not eligible to apply. Non-domestic (non-U.S.) components of U.S. Organizations are not eligible to apply. Foreign components, as defined in the NIH Grants Policy Statement, are allowed.
Agency Code: HHS-NIH11
Agency Name: Department of Health and Human Services
National Institutes of Health
Posted Date: Nov 18, 2019
Close Date: Jan 07, 2023
Last Updated Date: Nov 18, 2019
Award Ceiling: $0
Award Floor: $0
Estimated Total Program Funding:
Expected Number of Awards:
Description: The purpose of this Funding Opportunity Announcement (FOA) is to encourage exploratory or developmental research to improve the oral health of adolescents in the United States, and to reduce observed oral health disparities and inequities in this population. This FOA defines adolescents as those individuals between the ages of 10 and 19.
Version: 1

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ScienceDaily

Study casts doubt on carbon capture

One proposed method for reducing carbon dioxide (CO2) levels in the atmosphere — and reducing the risk of climate change — is to capture carbon from the air or prevent it from getting there in the first place. However, research from Mark Z. Jacobson at Stanford University, published in Energy and Environmental Science, suggests that carbon capture technologies can cause more harm than good.

“All sorts of scenarios have been developed under the assumption that carbon capture actually reduces substantial amounts of carbon. However, this research finds that it reduces only a small fraction of carbon emissions, and it usually increases air pollution,” said Jacobson, who is a professor of civil and environmental engineering. “Even if you have 100 percent capture from the capture equipment, it is still worse, from a social cost perspective, than replacing a coal or gas plant with a wind farm because carbon capture never reduces air pollution and always has a capture equipment cost. Wind replacing fossil fuels always reduces air pollution and never has a capture equipment cost.”

Jacobson, who is also a senior fellow at the Stanford Woods Institute for the Environment, examined public data from a coal with carbon capture electric power plant and a plant that removes carbon from the air directly. In both cases, electricity to run the carbon capture came from natural gas. He calculated the net CO2 reduction and total cost of the carbon capture process in each case, accounting for the electricity needed to run the carbon capture equipment, the combustion and upstream emissions resulting from that electricity, and, in the case of the coal plant, its upstream emissions. (Upstream emissions are emissions, including from leaks and combustion, from mining and transporting a fuel such as coal or natural gas.)

Common estimates of carbon capture technologies — which only look at the carbon captured from energy production at a fossil fuel plant itself and not upstream emissions — say carbon capture can remediate 85-90 percent of carbon emissions. Once Jacobson calculated all the emissions associated with these plants that could contribute to global warming, he converted them to the equivalent amount of carbon dioxide in order to compare his data with the standard estimate. He found that in both cases the equipment captured the equivalent of only 10-11 percent of the emissions they produced, averaged over 20 years.

This research also looked at the social cost of carbon capture — including air pollution, potential health problems, economic costs and overall contributions to climate change — and concluded that those are always similar to or higher than operating a fossil fuel plant without carbon capture and higher than not capturing carbon from the air at all. Even when the capture equipment is powered by renewable electricity, Jacobson concluded that it is always better to use the renewable electricity instead to replace coal or natural gas electricity or to do nothing, from a social cost perspective.

Given this analysis, Jacobson argued that the best solution is to instead focus on renewable options, such as wind or solar, replacing fossil fuels.

Efficiency and upstream emissions

This research is based on data from two real carbon capture plants, which both run on natural gas. The first is a coal plant with carbon capture equipment. The second plant is not attached to any energy-producing counterpart. Instead, it pulls existing carbon dioxide from the air using a chemical process.

Jacobson examined several scenarios to determine the actual and possible efficiencies of these two kinds of plants, including what would happen if the carbon capture technologies were run with renewable electricity rather than natural gas, and if the same amount of renewable electricity required to run the equipment were instead used to replace coal plant electricity.

While the standard estimate for the efficiency of carbon capture technologies is 85-90 percent, neither of these plants met that expectation. Even without accounting for upstream emissions, the equipment associated with the coal plant was only 55.4 percent efficient over 6 months, on average. With the upstream emissions included, Jacobson found that, on average over 20 years, the equipment captured only 10-11 percent of the total carbon dioxide equivalent emissions that it and the coal plant contributed. The air capture plant was also only 10-11 percent efficient, on average over 20 years, once Jacobson took into consideration its upstream emissions and the uncaptured and upstream emissions that came from operating the plant on natural gas.

Due to the high energy needs of carbon capture equipment, Jacobson concluded that the social cost of coal with carbon capture powered by natural gas was about 24 percent higher, over 20 years, than the coal without carbon capture. If the natural gas at that same plant were replaced with wind power, the social cost would still exceed that of doing nothing. Only when wind replaced coal itself did social costs decrease.

For both types of plants this suggests that, even if carbon capture equipment is able to capture 100 percent of the carbon it is designed to offset, the cost of manufacturing and running the equipment plus the cost of the air pollution it continues to allow or increases makes it less efficient than using those same resources to create renewable energy plants replacing coal or gas directly.

“Not only does carbon capture hardly work at existing plants, but there’s no way it can actually improve to be better than replacing coal or gas with wind or solar directly,” said Jacobson. “The latter will always be better, no matter what, in terms of the social cost. You can’t just ignore health costs or climate costs.”

This study did not consider what happens to carbon dioxide after it is captured but Jacobson suggests that most applications today, which are for industrial use, result in additional leakage of carbon dioxide back into the air.

Focusing on renewables

People propose that carbon capture could be useful in the future, even after we have stopped burning fossil fuels, to lower atmospheric carbon levels. Even assuming these technologies run on renewables, Jacobson maintains that the smarter investment is in options that are currently disconnected from the fossil fuel industry, such as reforestation — a natural version of air capture — and other forms of climate change solutions focused on eliminating other sources of emissions and pollution. These include reducing biomass burning, and reducing halogen, nitrous oxide and methane emissions.

“There is a lot of reliance on carbon capture in theoretical modeling, and by focusing on that as even a possibility, that diverts resources away from real solutions,” said Jacobson. “It gives people hope that you can keep fossil fuel power plants alive. It delays action. In fact, carbon capture and direct air capture are always opportunity costs.”

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ScienceDaily

Replacing coal with gas or renewables saves billions of gallons of water

The ongoing transition from coal to natural gas and renewables in the U.S. electricity sector is dramatically reducing the industry’s water use, a new Duke University study finds.

“While most attention has been focused on the climate and air quality benefits of switching from coal, this new study shows that the transition to natural gas — and even more so, to renewable energy sources — has resulted in saving billions of gallons of water,” said Avner Vengosh, professor of geochemistry and water quality at Duke’s Nicholas School of the Environment.

These savings in both water consumption and water withdrawal have come despite the intensification of water use associated with fracking and shale gas production, the new study shows.

“For every megawatt of electricity produced using natural gas instead of coal, the amount of water withdrawn from local rivers and groundwater is reduced by 10,500 gallons, the equivalent of a 100-day water supply for a typical American household,” said Andrew Kondash, a postdoctoral researcher at Duke, who led the study as part of his doctoral dissertation under Vengosh.

Water consumption — the amount of water used by a power plant and never returned to the environment — drops by 260 gallons per megawatt, he said.

At these rates of reduction, if the rise of shale gas as an energy source and the decline of coal continues through the next decade, by 2030 about 483 billion cubic meters of water will be saved each year, the Duke study predicts.

If all coal-fired power plants are converted to natural gas, the annual water savings will reach 12,250 billion gallons — that’s 260% of current annual U.S. industrial water use.

Although the magnitude of water use for coal mining and fracking is similar, cooling systems in natural gas power plants use much less water in general than those in coal plants. That can quickly add up to substantial savings, since 40% of all water use in the United States currently goes to cooling thermoelectric plants, Vengosh noted.

“The amount of water used for cooling thermoelectric plants eclipses all its other uses in the electricity sector, including for coal mining, coal washing, ore and gas transportation, drilling and fracking,” he said.

Even further savings could be realized by switching to solar or wind energy. The new study shows that the water intensity of these renewable energy sources, as measured by water use per kilowatt of electricity, is only 1% to 2% of coal or natural gas’s water intensity.

“Switching to solar or wind energy would eliminate much of the water withdrawals and water consumption for electricity generation in the U.S.,” Vengosh said.

Natural gas overtook coal as the primary fossil fuel for electricity generation in the United States in 2015, mainly due to the rise of unconventional shale gas exploration. In 2018, 35.1% of U.S. electricity came from natural gas, while 27.4% came from coal, 6.5% came from wind energy, and 2.3% came from solar energy, according to the U.S. Energy Information Administration (EIA).

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IEEE Spectrum

Simulation-Driven Optimization of 5G RF MEMS Filters

Efficiently design RF MEMS acoustic resonator-based filters, reducing cost, risk and time