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A Hidden Source Of Arctic Carbon | Earth Wise

April 24, 2020 By EarthWise Leave a Comment

Researchers from the University of Texas at Austin, the U.S. Fish and Wildlife Service, and Florida State University have published a paper presenting evidence of significant and previously undetected concentrations and fluxes of dissolved organic matter entering Arctic coastal waters. The source of the organic matter is groundwater flow atop the frozen permafrost. The groundwater moves from land to sea unseen, but the new research reveals that it carries significant concentrations of carbon and other nutrients to Arctic coastal food webs.

Globally, groundwater is important for delivering carbon and other nutrients to oceans, but in the Arctic, where much water is trapped in the permafrost, its role was thought to be minimal. But the new research reveals that groundwater may be contributing an amount of dissolved organic matter to the Alaskan Beaufort Sea that is comparable to what comes from neighboring rivers during the summer.

The researchers found that shallow groundwater flows beneath the surface and picks up new, young organic carbon and nitrogen, but it also mixes with layers of deeper soils and thawing permafrost, picking up and transporting century-to-millennia old organic carbon and nitrogen. This material is unique because it is directly transported to the ocean without seeing or being photodegraded by sunlight and may be valuable as a food source to bacteria and higher organisms that live in Arctic coastal waters.

The study concluded that the supply of leachable organic carbon from groundwater amounts to as much as 70% of the dissolved organic matter that enters the Beaufort Sea from rivers during the summer. The role that groundwater inputs play in Arctic coastal ecosystems will be an area of active research for years to come.

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Hidden Source of Carbon Found at the Arctic Coast

Photo, posted June 14, 2015, courtesy of Eugen Marculesco via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Working Forest Buffers | Earth Wise

April 15, 2020 By EarthWise Leave a Comment

More than 100,000 miles of U.S. rivers and streams are polluted by nitrogen and phosphorus, mostly from agricultural runoff. In the past, forests grew naturally alongside these waterways and helped stabilize stream banks and decrease flooding while trapping and filtering pollutants. But most of these forests have been cut down to make way for towns, cities, livestock, and crops.

Farmers are reluctant to retire valuable farmland with non-productive buffer planting. But in Pennsylvania, there is an innovative program that encourages farmers to plant cash crops in waterway buffer zones that can help stabilize stream banks and clean up the waterways. These plantings are called working buffers.

Strips of streamside land are replanted with native floodplain trees and shrubs. These are known as riparian forest buffers. Pennsylvania has instituted a grant program under which farmers and landowners plant these buffers and turn a profit.

Many of these buffers have three zones. A conventional forest buffer that can be just 15 feet wide is composed of native woodland and stabilizes the bank with tree roots and enhances wildlife habitat. A second zone, some 20 feet wide, is planted with trees and shrubs that can tolerate periodic flooding. Apart from slowing floodwater and taking up nutrients, this zone can provide profits by planting trees like black walnut, hazelnut, persimmon, and elderberry. Only hand harvesting is allowed. A third zone, adjacent to conventional crop, can contain blueberries, raspberries, and decorative woody florals.

How many farmers can be enticed to create these riparian buffers remains to be seen, but they do represent a way to help farmers to reduce pollution and turn a profit along the way.

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A Movement Grows to Help Farmers Reduce Pollution and Turn a Profit

Photo, posted March 19, 2010, courtesy of the USDA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Devastating Threat To Coral Reef Habitats | Earth Wise

March 25, 2020 By EarthWise 2 Comments

According to new research from scientists at the University of Hawaii Manoa, the warming and acidifying oceans could wipe out nearly all existing coral reef habitats by 2100. In fact, the researchers predict that 70-90% of coral reefs will disappear over the next 20 years alone as a consequence of climate change and pollution.

Some organizations are attempting to save coral habitats by transplanting live corals from labs to reefs. The idea is that the new young corals will help revive the reefs. But after mapping where such restoration efforts would be most successful, the research indicates that there will be little to no suitable habitat remaining for corals by 2100. Small portions of Baja California and the Red Sea are two of the sites that could remain viable by 2100, although neither are ideal due to their proximity to rivers. Sea surfaces temperature and acidity are two of the most important factors in determining the viability of a site for restoration.

Warming ocean waters stress corals, which cause them to expel the symbiotic algae living inside them. This turns the often colorful corals white – an event known as coral bleaching. Bleached corals are not dead corals, but they are at a higher risk of dying. These coral bleaching events are becoming more frequent as a result of the changing climate.

The projected increases in human pollution will only play a minor role in the future elimination of coral reef habitats. Ironically, that’s because humans have already caused such extensive damage to coral reefs that there aren’t many locations left to impact.

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Warming, acidic oceans may nearly eliminate coral reef habitats by 2100

Photo, posted September 28, 2009, courtesy of Matt Kieffer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Beavers And Biodiversity

October 10, 2019 By EarthWise Leave a Comment

Beavers are large, semi-aquatic rodents known best for their ability to construct dams, canals, and lodges (their homes). They are among the largest rodents in the world. With powerful jaws and strong teeth, beavers fell trees to use as building materials, often changing their environment in ways few other animals can. But in a good way. As it turns out, beavers are important for biodiversity.

According to new research from the Faculty of Natural Sciences at the University of Stirling in Scotland, reintroducing beavers to their native habitats is an important step towards solving the freshwater biodiversity crisis.

Researchers surveyed water plants and beetles in 20 wetlands in Sweden – 10 created by beavers and 10 that were not – in order to understand what impact beavers might have on the variety of plant and animal life around them.

The research team’s findings build on previous work that has shown that beavers have an important impact on biodiversity. This latest study discovered that the number of species found only in beaver-built ponds was 50% higher than in other non beaver-built wetlands in the same region.

Beavers are known to be profound engineers of the environment. They use wood to build dams across rivers in order to form ponds behind them. They do this to raise the water level in order to avoid predators, like bears and wolves. But it turns out many other plants and animals, like water plants and beetles, also benefit from their work.

According to the research team, reintroducing beavers to their native habitats should benefit the wider biodiversity and be seen as an important step towards solving the freshwater biodiversity crisis.

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Beaver reintroduction key to solving freshwater biodiversity crisis

Photo, posted October 2, 2014, courtesy of USFWS Midwest Region via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Renewable Natural Gas

September 30, 2019 By EarthWise Leave a Comment

Small-scale biogas systems have collected methane from landfills, sewage plants, and farms for decades. Here in the US, biogas is finally catching up with modern techniques with the advent of third-party operators introducing more sophisticated technology to capture methane and pump it directly into pipelines.

Renewable methane or natural gas represents a significant mostly unexploited source of energy. Examples include the vast amounts methane generated by manure from some of the 2,300 hog farms in eastern North Carolina, biodigesters that can turn clusters of large California dairy farms into energy hubs, as well as diverting food waste from landfills and transforming it into vehicle and heating fuels.

According to a 2014 EPA study, the U.S. could support at least 13,000 biogas facilities, fed by manure, landfill gas, and biosolids from sewage treatment plants. Those facilities could produce over 650 billion cubic feet of biogas per year – enough renewable energy to power 3 million homes.

A study by the World Resources Institute estimated that the 50 million tons of organic waste sent to landfills or incinerated every year in the U.S. has the energy content of 6 billion gallons of diesel fuel, amounting to 15% of all diesel consumed by heavy-duty trucks and buses.

Utilizing all that biogas could help lower greenhouse gas emissions from some of the most difficult sectors to decarbonize – transportation, industry, and heating buildings. In addition, ramped up renewable gas could keep organic waste out of landfills and prevent manure runoff into rivers and water supplies.

Renewable natural gas could be the next big thing in green energy.

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Could Renewable Natural Gas Be the Next Big Thing in Green Energy?

Photo, posted June 19, 2013, courtesy of Alan Levine via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Decline Of Earth’s Largest Freshwater Creatures

September 23, 2019 By EarthWise Leave a Comment

While nearly 70% of the globe is covered by water, only 2.5% of it is freshwater. The rest is saline and ocean-based. And only 1% of our freshwater is easily accessible, with much of it locked away in snowfields and glaciers.

Despite freshwater only making up a small fraction of all water on the planet, it’s home to one third of all vertebrate species. Some have survived hundreds of millions of years, but many of the world’s largest freshwater creatures – including fish, reptiles, amphibians, and mammals – may soon find themselves on the brink of extinction.

According to a study recently published in the journal Global Change Biology, scientists from the Leibniz-Institute of Freshwater Ecology and Inland Fisheries and international colleagues have quantified the global decline of freshwater megafauna for the first time. In four decades since 1970, the global populations of these freshwater giants have declined 88% – twice as much as the loss of vertebrate populations on land or in the oceans.

Freshwater megafauna include all freshwater animals that weigh 30 kilograms (about 66 pounds) or more, such as certain dolphins, beavers, crocodiles, turtles and sturgeons.

Overexploitation is one of the main threats to freshwater megafauna. (These animals are often targeted for their meat, eggs, and skin). The other main threat is the loss of free-flowing rivers. Many of the world’s large rivers are already highly fragmented, which impacts access to spawning and feeding grounds. The research team says another 3700 large dams are planned or under construction, including 800 in habitats rich with freshwater megafauna, including the Amazon, Congo, and Ganges river basins.

Current conservation measures are clearly failing our freshwater creatures.

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88 percent decline of big freshwater animals

Earth’s largest freshwater creatures at risk of extinction

Photo, posted March 25, 2012, courtesy of the U.S. Fish and Wildlife Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Antibiotics In The Environment

June 6, 2019 By EarthWise Leave a Comment

Antibiotics make their way into the environment in many ways. Sources of antibiotic pollution include the waste from large-scale animal farms and the wastewater from hospitals, municipalities, and antibiotic manufacturing.

A new study has discovered concentrations of antibiotics in some of the world’s rivers exceed safe levels by up to 300 times. In the project, researchers looked for 14 commonly used antibiotics in rivers in 72 countries across six continents. They found antibiotics at 65% of all the sites they examined.

The antibiotic ciproflaxacin was the compound that most frequently exceeded safe levels, surpassing that threshold in 51 places. The antibiotic metronidazole exceeded safe levels by the biggest margin. Concentrations of this antibiotic at one site in Bangladesh was 300 times greater than the safe level. The most prevalent antibiotic was trimethoprim. It was detected at 307 of the 711 sites.

Some of the world’s most iconic rivers were sampled as a part of this study, including the Danube, Mekong, Seine, Thames, Tiber and Tigris.

The project, which was led by the University of York, found that high-risk sites were often located near wastewater treatment systems, waste or sewage dumps, and in some areas of political unrest.

Safe levels for antibiotics, which were recently established by the AMR Industry Alliance, range from 20,000 to 32,000 nanograms per liter depending on the compound.

According to the research team, solutions to the problem of antibiotic contamination should include infrastructure investment, tighter regulation, and the remediation of already contaminated sites.

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Antibiotics found in some of the world’s rivers exceed ‘safe’ levels, global study finds

Photo, posted October 7, 2013, courtesy of Nicola via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

More Antarctic Warming

April 23, 2019 By EarthWise Leave a Comment

East Antarctica is the coldest place on Earth. It makes up two-thirds of the continent, is home to the South Pole, and has vast ice sheets that have been around for tens of millions of years and are nearly three miles thick in places. Temperatures there hover around 67 degrees below zero. In 2010, a few spots on East Antarctica’s polar plateau reached a record-breaking 144 degrees below zero.

But almost unbelievably, parts of the East Antarctic seem to be melting.

Scientists are seeing worrying signs of ice loss in the East Antarctic. Glaciers are starting to move more quickly and are dumping their ice into the Southern Ocean. Satellite images show the fast-moving ice. The biggest glacier – the Totten Glacier – alone contains enough ice to raise global sea levels by over 12 feet.

The Antarctic as a whole contains about 90% of the planet’s ice. In theory, if it all melted, it would raise global sea levels by an average of 200 feet.

The growing concerns about eastern Antarctica are not that its interior plateau will soon start to melt. It is still extremely cold there and should stay that way for a long time. But its edges, which are in contact with warming ocean waters, are the real worry. As the region’s ice shelves, which float atop the Southern Ocean, erode, the vast glaciers behind them could rapidly accelerate their slide into the sea.

Today, satellites show huge glaciers moving rapidly toward the coast, with wide rivers of ice sometimes moving several miles a year. In the face of rapid change and limited data, it is difficult to predict what the Antarctic will do in the future. But it doesn’t look good.

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Polar Warning: Even Antarctica’s Coldest Region Is Starting to Melt

Photo, posted January 3, 2013, courtesy of Christopher Michel via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Sand Mining And The Environment

April 2, 2019 By EarthWise Leave a Comment

In discussions of the environment, we don’t hear much about sand mining. But sand mining is the world’s largest mining endeavor, responsible for 85% of all mineral extraction. Sand and gravel are mined on a huge scale around the world. The UN estimates that the total exceeds 40 billion tons a year. Most of this activity is unregulated and unmeasured, and much of it is corrupt and environmentally destructive.

Concrete is the predominant use for sand. Every ton of cement requires six to seven tons of sand and gravel in order to make concrete. But sand also makes up 90% of asphalt on roads and it is used for land reclamation in places like Singapore. Sand is also widely used in industries such as glass manufacturing and fracking.

There are different sorts of sand. Desert sand is mostly useless for making concrete because its grains are too rounded by erosion and don’t bind well in the concrete. Marine sand is not great for concrete either because it has to be washed clean of corrosive salts.

As a result, salt miners mostly get sand from pits on land and dredged up from lakes and riverbeds. Dredging massive quantities of sand from rivers and lakes drastically alters river flow, erodes riverbanks, dries up tributaries, lowers water tables, and trashes wetlands and fisheries. In many countries, this even goes on in national parks where officials turn a blind eye to the activity. India is the world’s second-largest sand mining country (after China) and widespread illegal extraction occurs throughout the country run by highly organized and even violent “sand mafias.”

Sand mining is a huge problem and, to date, is one that is pretty much off of most people’s radar.

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The Hidden Environmental Toll of Mining the World’s Sand

Photo, posted June 3, 2017, courtesy of Andrey Talalov via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Glaciers And Water Supply

March 25, 2019 By EarthWise Leave a Comment

The world has roughly 150,000 glaciers covering about 200,000 square miles of the earth’s surface. Over the last 40 years they’ve lost the equivalent of a layer of ice 70 feet thick. Most of them are getting shorter as well. Some have shrunk to nothing; many smaller glaciers in places like the Rockies and the Andes have disappeared entirely.

Glaciers represent the snows of centuries, compressed over time to form flowing rivers of ice. They always change over time, accumulating snow in winter and losing ice to melting in summer. But in recent times, the warming climate has allowed the melting to outpace the accumulation.

Much of the discussion about the retreating glaciers relates to sea level rise, catastrophic floods, debris flow, and the effects on rivers and ecosystems.

But in some places, the biggest impact of the loss of glaciers is on the supply of water for people and agriculture. In Kazakhstan, Almaty, the country’s largest city depends on glacier-fed rivers for drinking water for its 2 million people and for irrigation water for crops. All across the Tibetan Plateau and the Himalayan and Karakmoram mountain ranges, hundreds of millions of people rely on glacier-fed rivers for their water supplies.

A melting glacier can at first increase stream flow but eventually reaches a tipping point and meltwater begins to taper. In the short term, the melting glaciers may provide increased amounts of water coming down from the mountains, but eventually the flow in the rivers will begin to decline and populations will face a crisis.

It will be essential for people in many places to carefully plan for their future water needs in a changing world.

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Glaciers Are Retreating. Millions Rely on Their Water.

Photo, posted September 16, 2011, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Problem Of Microplastics

February 15, 2019 By EarthWise Leave a Comment

In recent years, there have been multiple reports of microplastic contamination seemingly everywhere: in the ocean, in lakes and rivers, in beverages and foods, and in the bodies of birds, fish, and even people. As the world tries to come to grips with this growing problem, there are many things that we simply don’t know.

Microplastics are usually formed by the breakdown of larger pieces of plastic. Shopping bags and cups degrade into microplastics. Microfiber clothing generates microplastics in washing machines. And some manufacturers still intentionally add microplastics to personal care products like toothpaste and facial scrubs.

Technically, a microplastic is any piece of plastic measuring five millimeters in size down to one micron – which is one thousandth of a millimeter. But there can be even smaller plastic particles classified as sub-microplastics and even nanoplastics.

A real concern is that it is not actually clear how dangerous microplastics are for living organisms. We know that aquatic and terrestrial species – including humans – can and do absorb microplastic particles, but whether there is actual toxicity and the nature of any detrimental effects is not yet well understood.

Another real problem is that it is actually not easy to distinguish microplastics from other particles in a given sample. When you are looking at a particle that is smaller than a millimeter in size, it is not easy to tell whether it is a grain of sand, a bit of cellulose from a plant, or a microplastic. There are reliable and definitive ways to analyze samples for microplastics, but they are not as simple and commonplace as just looking through a microscope.

Microplastics are a rapidly growing problem and we don’t even really know how big and how bad the problem is.

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How dangerous is microplastic?

Photo, posted January 10, 2015, courtesy of Daria Nepriakhina via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saved By The Trees

February 1, 2019 By EarthWise Leave a Comment

The island of Kokota, part of the Zanzibar Archipelago off the coast of Tanzania, is tiny – only one square kilometer and home to just 500 people. For centuries, its residents subsisted by harvesting the islet’s natural resources, including its trees.

By the early 21st century, the deforestation had become unsustainable and the islanders faced a crisis. Fisheries were depleted, and rivers ran dry. The changing climate brought rising sea levels, more erratic rainfall, and coral bleaching in the surrounding waters. The situation looked hopeless.

But in recent years, the island has come back from the brink of ruin. Reforestation efforts began in 2008 on the larger island of Pemba and on Kokota itself, led by a Pemba local and a Canadian tree planter who formed the non-profit Community Forests International. Since then, nearly 2 million trees have been planted on the two islands. Enthusiastic volunteers on Kokota usually help plant trees during the rainy season, when water is plentiful.

Community Forests International, along with spearheading the tree planting effort, also built Kokota’s first school, and installed rainwater storage tanks for the community.

The conservation group is now devising ways for Kokota to make more money by diversifying its agriculture with crops that grow well in its climate including spices like cloves, cinnamon, and nutmeg. They are also helping locals to grow more and different vegetables in their gardens.

Small, poor communities are often the most vulnerable to the effects of climate change, such as drought, powerful storms, and depleted fisheries. Tiny Kokota provides an example of an environmental comeback. Fighting climate change requires economic solutions along with environmental solutions. For this one tiny island, it appears to have been saved by the trees.

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