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Soil Erosion: Scientists discover Earliest Human Impact on Environment

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Soil Erosion has a huge impact on environment. VOA
  • Scientists have discovered wide rates of erosion dating back to 11,500 years ago from the Dead Sea in Israel
  • the erosion occurred during the Neolithic Revolution
  • The discovery took place as part of the Dead Sea Deep Drilling Project

New York, June 6, 2017: Scientists have discovered wide rates of erosion dating back to 11,500 years ago from the Dead Sea in Israel — touted as the oldest geological evidence of man-made impact on the environment.

The discovery took place as part of the Dead Sea Deep Drilling project, which harnessed a 1,500-foot-deep drill core to delve into the Dead Sea basin.

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The core sample, which provided the researchers with a sediment record of the last 220,000 years, showed basin-wide erosion rates dramatically opposite to the known tectonic and climatic regimes of the period.

We noted a sharp threefold increase in the fine sand that was carried into the Dead Sea by seasonal floods. This intensified erosion is incompatible with tectonic and climatic regimes during the Holocene, the geological epoch that began after the Pleistocene some 11,700 years ago, said lead author Shmuel Marco, Professor at the Tel Aviv University in Israel.

The study, published in the journal Global and Planetary Change, showed that the erosion occurred during the Neolithic Revolution, the wide-scale transition of human cultures from hunting and gathering to agriculture and settlement. The shift resulted in an exponentially larger human population on the planet.

Natural vegetation was replaced by crops, animals were domesticated, grazing reduced the natural plant cover, and deforestation provided more area for grazing, Marco said.

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All these resulted in the intensified erosion of the surface and increased sedimentation, which we discovered in the Dead Sea core sample, he added.

The researchers are currently in the process of recovering the record of earthquakes from the same drill core.

We have identified disturbances in the sediment layers that were triggered by the shaking of the lake bottom. It will provide us with a 220,000-year record — the most extensive earthquake record in the world, Marco said. (IANS)

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Women of America Are Stepping Up As Nuclear Energy Advocates

Nuclear power is clean, safe and better for the environment than some alternative energy sources

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Engineering manager Kristin Zaitz and her co-worker Heather Matteson, a reactor operator, started Mothers for Nuclear. VOA
  • The availability of cheap natural gas and greater energy efficiency has reduced demand for nuclear energy in recent years
  • Nuclear power is clean, safe and better for the environment than some alternative energy sources
  • Industry experts say that women who work in nuclear power can be powerful advocates for nuclear

San Francisco, August 26, 2017: Kristin Zaitz is confident that her nuclear power plant is safe.

Zaitz, an engineering manager, was at Diablo Canyon Power Plant during both her pregnancies and has scuba dived to inspect the plant, which hugs the California coast. Zaitz wears a pendant with a tiny bit of uranium inside, an item that tends to invite questions.

“We all have our perceptions of nuclear,” Zaitz said.

In a few years, Diablo Canyon will close, part of a trend nationwide. The availability of cheap natural gas and greater energy efficiency has reduced demand for nuclear energy in recent years. Add to that ongoing concerns about public safety, such as those raised by memories of disasters at nuclear power plants in Fukushima, Japan, Chernobyl in Ukraine (then part of the Soviet Union) and Three Mile Island in the United States.

Nuclear is ‘cleaner’ than fossil fuels

Supporters of nuclear energy say that when a reactor-based generating station closes, not enough wind and solar power is available to make up the difference. They lament that energy companies tend to turn instead to fossil fuels — coal and natural gas — which produce environmentally harmful emissions.

Zaitz and her co-worker Heather Matteson, a reactor operator, started Mothers for Nuclear, their effort to get the word out that nuclear power is clean, safe and better for the environment than some alternative energy sources.

“I went into the plant very skeptical of nuclear and being scared of it,” said Matteson. “It took me six to seven years to really feel like this is something good for the environment. I don’t want people to take six to seven years to make that decision. We don’t have that long.”

Matteson, too, wears the uranium necklace as a conversation starter. “Nuclear is fun,” she said. Is there any radiation emitted by the pendant? “There’s slightly more than from a banana,” she conceded.

Also Read: Indian nuclear industry growing fast, says former Atomic Energy Commission chief

Women seen as powerful advocates

Industry experts say that women who work in nuclear power can be powerful advocates for nuclear. They can help change attitudes of other women who tend to be more skeptical than men about nuclear energy’s benefits.

At the recent U.S. Women in Nuclear conference in San Francisco, women working in the industry talked about how more should be done to make nuclear power’s case to the public, and how they may be the best suited to do it.

“As mothers, I think we also have an important role to play in letting the public know that we support nuclear for the future, for our children,” said Matteson. “And we don’t know other mothers supporting nuclear power in a vocal way. We thought there was a gap to fill.”

Young women say they look at careers in this industry because they are socially minded.

‘Do something good for the world’

“I went into this wanting to do something good for the world,” Lenka Kollar, business strategy director at NuScale, a firm in Oregon that designs and markets small modular reactors. “Wanting to bring power to people. There are still more than a billion people in the world who don’t have electricity.”

Critics of nuclear energy say it doesn’t matter who is promoting it.

“Using mothers’ voices to argue for a technology that is fundamentally dangerous and that has been demonstrated by disasters like Fukushima to be not safe for the communities that surround the power plants or even cities that are hundreds of miles away is disingenuous,” said Kendra Klein, a staff scientist with Friends of the Earth, an environmental group.

While the future of nuclear power in the United States may be uncertain, the women here say they have a positive story to tell. (VOA)

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Street View Car Map by Google Locates Methane Gas Leaks

Colorado State University biologist Joe Von Fisher helped enable a street view of Methane leaks in the city with the help of Google maps

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Colorado State University
Gas Leak. Wikimedia

August 04, 2017: Finding underground methane gas leaks is now as easy as finding a McDonalds, thanks to a combination of Google Street View cars, mobile methane detectors, some major computing power and a lot of ingenuity.

When a city’s underground gas lines leak, they waste fuel and release invisible plumes of methane, a potent greenhouse gas. To find and measure leaks, Colorado State University biologist Joe von Fischer decided to create “methane maps,” to make it easier for utilities to identify the biggest leaks, and repair them.

“That’s where you get the greatest bang for the buck,” he pointed out, “the greatest pollution reductions per repair.”

Knowing that Google Maps start with Google Street View cars recording everything they drive by, along with their GPS locations, von Fischer’s team thought they would just add methane detectors to a Street View car. It turned out, it was not that simple.

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“Squirrelly objects”

The world’s best methane detectors are accurate in an area the size of a teacup, but methane leaks can be wider than a street. Also, no one had ever measured the size of a methane leak from a moving car.

“If you’ve ever seen a plume of smoke, it’s sort of a lumpy, irregular object,” von Fischer said. “Methane plumes as they come out of the ground are the same, they’re lumpy squirrelly objects.”

The team had to develop a way to capture data about those plumes, one that would be accurate in the real world. They set up a test site in an abandoned airfield near campus and brought in what looked like a large scuba tank filled with methane and some air hoses. Then they released carefully measured methane through the hose as von Fischer drove a specially equipped SUV past it, again and again.

They compared readings from the methane detectors in the SUV to readings from the tank.

“We spend a lot of time driving through the plumes to sort of calibrate the way that those cars see methane plumes that form as methane’s being emitted from the ground,” von Fischer explained.

With that understanding, the methane detectors hit the road.

Also Read: This fiber material can sense odorless fuel leaks


Turning data into maps

But the results created pages of data, “more than 30 million points,” said CSU computer scientist Johnson Kathkikiaran. He knew that all those data points alone would never help people find the biggest leaks on any map. So he and his advisor, Sanmi Peracara, turned the data into pictures using tools from Google.

Their visual summaries made it easy for utility experts to analyze the methane maps, but von Fischer wanted anyone to be able to identify the worst leaks. His teammates at the Environmental Defense Fund met that challenge by incorporating the data into their online maps. Yellow dots indicate a small methane leak. Orange is a medium-sized one. Red means a big leak – as much pollution as one car driving 14,000 kilometers in a single day.

Von Fischer says that if a city focuses on these biggest leaks, repairing just 8 percent of them can reduce methane pollution by a third.

“That becomes a win-win type scenario,” he said, “because we’re not asking polluters to fix everything, but we’re looking for a reduction in overall emissions, and I think we can achieve that in a more cost effective way.”

After analyzing a methane map for the state of New Jersey, for example, the utility PSE&G has prioritized fixing its leakiest pipes there first, to speed the reduction of their overall pollution.

“To me that was a real victory, to be able to help the utility find which parts were leakiest, and to make a cost effective reduction in their overall emissions,” von Fischer said.

Von Fischer envisions, even more, innovation ahead for mapping many kinds of pollution… to clean the air and save energy. (VOA)

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Saving Farms from Slow Death called “Erosion” : Farmers believe Healthy Soils Yield Healthy Profits

A short drive away, in a neighbor's conventionally tilled field, soybeans grow in neat and tidy lines on a clean slate of bare earth

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farmers need to learn tilled soil erodes more easily and holds less water
University of Maryland soil scientist Ray Weil says that farmers need to learn tilled soil erodes more easily and holds less water. VOA
  • Experts worldwide are working to persuade farmers to reject thousands of years of agricultural tradition in order to save their soil
  • Building healthy soil and buffering themselves against climate change — and saving money while doing it — are all possible by practicing what is called conservation agriculture
  • Most farmers worldwide still plow their soil and leave it bare in the off-season, that causes the important nutrients to be washed away

July 25, 2017: Ancient civilizations plowed themselves into oblivion, and modern agriculture risks doing it again, geologist David Montgomery says.

In his new book, Montgomery says a growing number of farmers are using techniques that can save their farms from slow death by erosion.

In ‘Growing a Revolution: Bringing Our Soil Back to Life’, Montgomery meets farmers who are building healthy soil and buffering themselves against climate change — and saving money while doing it — by practicing what is called conservation agriculture.

Experts worldwide are working to persuade farmers to reject thousands of years of agricultural tradition in order to save their soil.

Erosion of Civilizations

Montgomery told VOA, while finishing his previous book, Dirt: The Erosion of Civilizations, “It was very difficult to write the final chapter and not have it sound really depressing.”

Dirt describes how tillage, one of the oldest practices in agriculture, degraded farms and civilizations from Mesopotamia to 1930’s Dust Bowl America.

Farmers till the soil to control weeds and make planting easier, but exposed soil washes away in the rain and blows away in the wind, carrying with it the nutrients plants need to thrive.

And yet, most farmers worldwide still plow their soil and leave it bare in the off-season. Many plant the same crops over and over again. All three practices wear out the soil.

Growing a Revolution picks up where Dirt ends, with the promise of a relatively new kind of farming.

“Conservation agriculture flip[s] all three of those ideas on their head,” he said. “It’s a completely different philosophy to not till, to always have the ground covered with either a commercial crop or a cover crop, and to grow a much more diverse rotation.”

ALSO READ: With vast untapped potential in Agriculture, Africa seeks Agricultural Transformation with India’s Help

Trouble in tidy fields

Trey Hill of Maryland has not tilled his soybean field in years. The young crop peeks out from below waist-high brown stalks of what remains of last year’s cover crop, a mix of grains, legumes, radishes and more.

“If you don’t like your fields to look like a mess,” Hill said with a laugh, “it has to kind of grow on you. Yet, I have a lot of other owners and peers that are, like, ‘Wow, what you’re doing is really exciting.'”

A short drive away, in a neighbor’s conventionally tilled field, soybeans grow in neat and tidy lines on a clean slate of bare earth.

University of Maryland soil scientist Ray Weil sees signs of trouble. The lower leaves of the soybean plants are splashed with mud from a rainstorm two nights earlier.

“When it rained, that soil went flying,” Weil said. “When the soil goes flying, it goes running down the slope. That’s the first step in soil erosion.”

Just a few millimeters below the surface, he finds soybean roots growing sideways, unable to penetrate a layer of hard earth packed down by the effects of tillage. If it turns dry later in the summer, he said, “they’re going to be crying uncle for water.”

‘Farming ugly’

“When no-till started, they called it ‘farming ugly,'” Weil said.

Hill’s “ugly” field is pretty on the inside. The roots of the cover crop he planted last year held onto the soil and its precious nutrients through the winter. Legumes added nitrogen, a key fertilizer. Earthworms feasting on the decomposing plants dig tunnels in the earth. Those pores soak up rainfall like a sponge, and they provide paths for the roots of Hill’s soybeans to grow through.

Cushioning against droughts and downpours, these soils help Hill through the weather extremes that are becoming more frequent with climate change.

And Hill is saving money. Less tilling means paying for less tractor fuel. He buys less fertilizer because his cover crops feed the soil.

“It all means more income to the farmer,” Hill said.

Profits for big and small farms

Conservation agriculture is also working on small farms in the developing world.

“What surprised me was how profitable these techniques can be in both settings,” Montgomery said.

Montgomery visited Ghana, where traditional slash-and-burn farming is degrading the soil, but conservation agriculture is turning fields into food forests. Farmers raised multiple crops on the same field, keeping the ground covered year ’round.

“You would have, say, an overstory of plantains and an understory of peppers and cassava,” he said. “If I’d squinted and didn’t know better, I might have sworn I was in a jungle, but everything around me was food.”

The spread of conservation agriculture has been slow. The transition can take several years. Weeds can cut yields in that time. Equipment designed to work on bare earth may not operate on cover-cropped fields.

Developing world farmers, in particular, often remove the residues of one crop before planting the next, to feed livestock, thatch roofs, or use as cooking fuel.

“There’s lots of uses,” Weil said. “But the residues need to be left in the field, at least most of them, to feed the soil.”

“Lots of barriers to giving it a try,” he added. “But once you get going, it’s cheaper.”

Cheaper, soil-saving and climate-friendly, experts worldwide are helping farmers switch to conservation agriculture and consign the plow to the history books. (VOA)


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