debris

Compost And Landfills | Earth Wise

January 19, 2021 By EarthWise Leave a Comment

Composting is popular as a way to keep solid waste out of landfills and many people turn much of their kitchen waste into rich soil amendments. Cities and towns across the country have composting programs that collect waste from residents to produce large quantities of compost rather than adding the waste to landfills. A new study from North Carolina State University looked into the environmental benefits of actually using compost at landfills.

Most municipal composting programs require that the compost they produce gets used “beneficially”. The new research shows that using compost as an alternative daily cover at landfills is competitive and often superior to the use of compost as a soil amendment in terms of its environmental benefits.

Landfills apply a layer of daily cover to reduce odors, reduce windblown debris, and keep vermin out of landfill waste. Federal regulations require six inches of soil as a daily cover.

Compost from food waste in particular is not always suitable for soil amendment in gardens and agricultural fields because it often contains broken glass and other contaminants.

The North Carolina State study looked at the environmental impact of using compost as daily cover in landfills compared with its use as a soil amendment. They looked at global warming potential, acidification potential, eutrophication (which is the amount of nutrients released to ground and surface water), cumulative energy demand, and the depletion of resources.

The study concluded that using compost as landfill daily cover is environmentally superior with regard to eutrophication, acidification, and global warming potential. On the other hand, soil amendment was better in terms of resource depletion and cumulative energy demand.

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Applying Compost to Landfills Could Have Environmental Benefits

Photo, posted April 22, 2008, courtesy of Alachua County via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Getting Value From Plastic Waste | Earth Wise

November 30, 2020 By EarthWise Leave a Comment

To date, the world has produced more than five billion tons of plastic and is making more all the time. Based on the way things are currently done, most of that will end up in landfills or in the natural environment. By 2050, the amount of plastic is expected to exceed 13 billion tons. This is one of the world’s biggest environmental problems.

Recently, an international collaboration by universities and institutions in the UK, China, and Saudi Arabia has developed a method of converting plastic waste into hydrogen gas and high-value solid carbon.

The technique was achieved with a new type of catalysis that uses microwaves to activate catalyst particles that effectively strip hydrogen from plastic polymers. The work was recently published in the journal Nature Catalysis and details how the researchers mixed mechanically pulverized plastic particles with a microwave-susceptor catalyst of iron oxide and aluminum oxide. That mixture was then subjected to microwave treatment and yielded a large volume of hydrogen gas and a residue of carbonaceous material, most of which was identified as carbon nanotubes.

The process is more rapid than most methods for dealing with plastic waste and can extract over 97% of the hydrogen in plastic without producing any carbon dioxide emissions.

The new method represents an attractive potential solution to the problem of plastic waste. Instead of polluting the planet, plastics could become a valuable feedstock for producing clean hydrogen fuel as well as valuable carbon materials. Proponents of the so-called hydrogen economy have continued to seek a green and economical way to produce hydrogen. This new work might be just what they are looking for.

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Turning plastic waste into hydrogen and high-value carbons

Photo, posted April 21, 2007, courtesy of Redwin Law via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Microplastics And Florida’s Birds of Prey | Earth Wise

June 19, 2020 By EarthWise Leave a Comment

Plastic debris comes in all different shapes and sizes, but those that are less than five millimeters in length are called microplastics. Some microplastics come from larger plastic debris that degrades into smaller bits over time. Another type of microplastics – called microbeads – are intentionally manufactured tiny plastic beads that are added as exfoliants to some health and beauty products.

According to a new study published in the journal Environmental Pollution, researchers have confirmed and quantified the presence of microplastics in terrestrial and aquatic birds of prey in Florida for the first time. This research is important because these birds of prey, including ospreys, hawks, and owls, are critical to maintaining a healthy ecosystem. The accumulation of microplastics in their digestive systems could lead to a myriad of health issues, including starvation.

Working with the Audubon Center for Birds of Prey in Florida, the research team from the University of Central Florida was able to examine the stomachs of 63 deceased birds. The team found microplastics in every bird it examined, extracting nearly 1,200 pieces of plastic in total. Microfibers represented 86% of the plastic pieces.

It’s common for plastic microfibers to enter ecosystems through the wastewater from washing machines. A 2016 study found that 700,000 plastic fibers come off in a typical wash. While there are lots of variables, synthetic fabrics account for 60% of the material used in clothing worldwide.

To help cut down on plastic in the environment, the research team suggests removing plastics from open landfills, purchasing only natural fabrics and clothing, and modifying water treatment facilities to capture microplastics.

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Microplastics found in Florida’s birds of prey for first time

Photo, posted April 15, 2016, courtesy of Andy Morffew via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Microplastic Hotspots In The Ocean | Earth Wise

June 4, 2020 By EarthWise Leave a Comment

Many of us are aware of the infamous ocean “garbage patches” of floating plastic. The Great Pacific Garbage Patch is roughly the size of Texas. But over 10 million tons of plastic waste enter the oceans each year and the floating patches only account for 1% of that total. The remaining 99% of the plastic ends up in the deep ocean, generally in the form of microplastics – tiny fragments of large plastic debris that have broken down as well as manufactured polyethylene beads used in various products.

According to a new study published in the journal Science, there are actually microplastic hotspots on the ocean floor, formed by deep-sea currents that act as conveyer belts moving the tiny plastic fragments around. One of these hotspots – in the Tyrrhenian Sea off the west coast of Italy – contained 1.9 million microplastic pieces in just one square meter of seafloor. This is the highest reported value for any place in the world.

Because of their small size, microplastics can be ingested by organisms across all levels of the marine food chain and eventually find their way into human diets.

The spatial distribution and ultimate fate of ocean microplastics are strongly controlled by near-bed thermohaline currents. These are deep-ocean currents driven by differences in water density, which is controlled by temperature and salinity. Thermohaline currents are known to supply oxygen and nutrients to the flora and fauna found at the ocean bottom. As a result, deep sea biodiversity hotspots are likely to be in same places where there are microplastic hotspots.

The discovery of these deep- sea hotspots is just another reason why we need behavior and policy interventions to limit the flow of plastics into natural environments.

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Seafloor microplastic hotspots controlled by deep-sea circulation

Photo, posted September 6, 2012, courtesy of Oregon State University via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Mistaking Plastic For Food

September 27, 2019 By EarthWise Leave a Comment

Green sea turtles are one of the world’s largest species of turtle, with some measuring close to four feet long and weighing up to nearly 300 pounds. Their range extends throughout tropical and subtropical seas around the world, with the largest nesting populations found in Costa Rica and Australia.

Green sea turtles get their name from the green layer of fat under their shell, as opposed to their shell itself, which can be brown, green, yellow, and/or black. Scientists believe the green coloring of their fat is a result of their diet. Unlike most other sea turtles, green sea turtles eat marine plants such as seaweed and seagrass.

But new research suggests that green sea turtles are also more likely to swallow plastic because it resembles their natural diet. The scientists from the University of Exeter and the Society for the Protection of Turtles who examined green sea turtles that washed up on beaches in Cyprus found they favored narrow lengths of plastic in natural colors (like green and black) as opposed to debris of other shapes and colors.

Researchers were able to examine the full gastrointestinal tract of 19 green sea turtles. They found pieces of plastic inside every one of them, with the number of pieces ranging from three to 183. Smaller turtles tended to contain more plastic, possibly because they are less experienced or because diet choices change with age and size.

Previous research has suggested that leatherback sea turtles also eat plastic that resembles their food: jellyfish.

Researchers hope these findings will help motivate us to continue to work on reducing our overall plastic consumption and pollution.

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Green turtles eat plastic that looks like their food

Photo, posted September, 2007, courtesy of Brock Roseberry via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

High-Tide Flooding And Pollution

April 30, 2019 By EarthWise Leave a Comment

Global sea levels are steadily rising. They are up 8 inches in the past century and now increasing at an average of 1.3 inches per decade. As a result, the incidence of high-tide “sunny day” flooding is on the rise, especially along the U.S. East Coast.

Norfolk Virginia experienced fewer than 2 days of high-tide flooding a year in the 1960s; it had 14 in 2017. Up and down the East Coast, flood days have increased by factors of 5 and more.

This has led to a form of pollution that hasn’t gathered much attention in the past: when these floodwaters recede, they can carry debris, toxic pollutants and excess nutrients into rivers, bays, and oceans.

In the aftermath of high-tide flooding in Norfolk, Chesapeake Bay was littered with tipped-over garbage cans, tossed-away hamburgers, oil, dirty diapers, pet waste and all manner of other things. Water that comes up on the landscape takes everything back into the river or ocean with it.

Analysis of tidal flooding along the Lafayette River in Norfolk indicated that just one morning of tidal flooding poured nearly the entire EPA annual allocation of nitrogen runoff for the river – nearly 2,000 pounds – into Chesapeake Bay. The effects of excess nitrogen in the water are well-known and responsible for the toxic algal blooms that endanger aquatic life as well as human health.

According to the National Oceanic and Atmospheric Administration, high-tide flooding frequency along the southeastern coast of the U.S. rose 160% since 2000. With the expected continuing rises in sea level, NOAA projects that as many as 85 days of high-tide flooding will occur along the coast by the year 2050. It’s a big problem.

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As High-Tide Flooding Worsens, More Pollution Is Washing to the Sea

Photo, posted September 20, 2018, courtesy of SC National Guard via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Balloons And Seabirds

March 19, 2019 By EarthWise Leave a Comment

It’s no secret that there is a ton of plastic in the ocean – millions of tons, in fact. Scientists estimate that there is more 165 million tons of plastics swirling about in our oceans today, with an additional 8.8 million tons flowing in every year. As the oceans swell with plastic debris, many marine species wind up ingesting the stuff – often with dire consequences.

All this plastic trash winds up affecting more than just aquatic species, too. According to researchers from the University of Tasmania, a seabird that ingested a single piece of plastic has a 20% chance of mortality. This statistic jumps to 50% if the seabird consumes nine pieces of plastic.

The study, which was recently published in the journal Scientific Reports, also found that while hard plastics account for the majority of plastic debris ingested, it’s far less likely to prove fatal than soft plastics, such as balloons.

In fact, the researchers found that balloons or balloon fragments were the number one marine debris risk of mortality for seabirds, killing almost one in five of the seabirds that ingested them.

The leading cause of death among the seabirds studied was blockage of the gastrointestinal tract. While soft plastics only accounted for 5% of the ingested plastics, they were responsible for more than 40% of seabird mortality. But the researchers make clear that hard plastics were still responsible for more than half of the study’s seabird deaths.

If we want to reduce the number of marine species dying from plastic ingestion, we need to reduce the volume of plastic going into the ocean and do what we can to remove what’s already there.

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Balloons the number 1 marine debris risk of mortality for seabirds

Photo, posted July 24, 2014, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Turning Plastic Waste Into Green Energy

November 14, 2018 By EarthWise 1 Comment

**In the Back to the Future movies, the DeLorean time machine ran on garbage. We aren’t any closer to building time machines, but it might soon be practical to produce fuel from garbage.**

Wildfires And The Water Supply

November 12, 2018 By EarthWise Leave a Comment

Hotter and dryer conditions are leading to an increasing number of wildfires in North America and elsewhere around the world. The damage they cause is well-known. But one aspect of that damage that tends to be overlooked is the impact on aquatic environments and drinking water supplies.

Cleaning Up the Garbage Patch

October 16, 2018 By EarthWise Leave a Comment

We have been talking about the Great Pacific Garbage Patch for several years. Two years ago, we reported on the activities of a company called Ocean Cleanup, founded five years ago by an 18-year-old Dutch entrepreneur named Boyan Slat. Two years ago, the company was conducting comprehensive surveys of the patch, which covers an area twice the size of Texas and contains some 80,000 tons of plastic debris.

An Accidental Plastic Eater

May 29, 2018 By EarthWise Leave a Comment

A couple of years ago, scientists in Japan discovered bacteria at a recycling plant that were breaking down a type of plastic called polyethylene terephthalate, or PET. With the world facing a growing plastic pollution problem, British and American researchers began to study the enzyme that the bacteria were using to try to understand how it works.

The Great Pacific Garbage Patch

May 9, 2018 By EarthWise Leave a Comment

The Great Pacific Garbage Patch is the world’s largest collection of floating trash. It lies between California and Hawaii and is popularly described as being larger than Texas. It was discovered in 1997 by a yachtsman who sailed through a mess of floating plastic bottles and other debris while on a voyage between Hawaii and Los Angeles.

Tsunami And Invasive Species

November 13, 2017 By EarthWise Leave a Comment

According to a new study published in the journal Science, scientists have discovered that hundreds of Japanese marine species have been swept across the Pacific Ocean to the United States following the deadly Tsunami in 2011.

A Plastics Promise

July 19, 2017 By EarthWise

It’s estimated that five to thirteen million tons of plastic enters our oceans annually, where much of it can linger for hundreds of years. According to a report by the World Economic Forum and the Ellen MacArthur Foundation, scientists estimate that there is 165 million tons of plastic swirling about in the oceans right now. And we are on pace to have more plastic than fish (by weight) in the world’s oceans by 2050. That’s some scary stuff.

[Read more…] about A Plastics Promise

Pollution In The Middle Of Nowhere

July 10, 2017 By EarthWise

The Pitcairn Islands are a group of four volcanic islands in the South Pacific, mostly known from the famed mutiny on the British ship Bounty. Pitcairn Island itself is where many of the mutineers settled and where some of their descendants live today. That small island, with a population of 57, is the only one of the group that is inhabited.

Baltimore’s Trash Wheels

April 10, 2017 By EarthWise

Baltimore’s harbor is cleaner than it has been in decades thanks to the efforts of two solar- and hydro-powered trash interceptors built to look like googly-eyed cartoon characters. In fact, they are known as Mr. Trash Wheel and Professor Trash Wheel.

Ocean Cleanup Progress Report

October 24, 2016 By WAMC WEB

Back in June, we talked about The Ocean Cleanup, a Dutch foundation founded in 2013 by an 18-year-old named Boyan Slat, which is developing technologies to rid the oceans of the vast collections of plastic that have been accumulating over the past 50 years.

Repurposing Ocean Plastic

October 20, 2016 By WAMC WEB

Scientists estimate that there is more than 165 million tons of plastic swirling about in our oceans today. And another 8.8 million tons of plastic ends up in oceans every year. According to a recent report from the World Economic Forum and the Ellen MacArthur Foundation, there could be more plastic by weight than fish by 2050 if current trends continue.