plant matter

Plastic from food waste

April 9, 2025 By EarthWise Leave a Comment

Plastic waste management is a complicated business. Most methods of recycling or breaking down plastic are costly and harmful to the environment. The most common biodegradable alternatives – like paper straws – are less than ideal replacements.

There are many approaches to creating biodegradable plastics using feedstocks like seaweed, sugarcane, and other plant matter. However, the resulting plastics often fall short compared with conventional petroleum-based plastics.

One type of bioplastic that is gaining popularity is polyhydroxyalkanoates, or PHA. PHA is a plastic produced by microorganisms. It is fully compostable or biodegradable but in other ways but looks, feels, and functions like regular plastic but without the environmental drawbacks.

PHA can be made using bacterial fermentation of a variety of feedstocks such as vegetable oils, sugars, starches, and even methane and wastewater.

Researchers at a startup from the University of Waterloo in Canada called MetaCycler BioInnovations have developed a process for producing PHA based on bacteria that has been engineered to convert waste from milk and cheese production. This solution upcycles waste from the dairy industry into cost-effective, sustainable bio-based plastics.

PHAs can be tailored to have a wide range of properties ranging from being rigid and tough to being quite flexible. Therefore, they can be suitable for many applications including packaging, agricultural films, and consumer goods.

The Waterloo technology is a way to tackle the problems of both food waste and plastic pollution with one solution.

**********

Web Links

Turning food waste into a new bioplastic

Photo, posted December 10, 2017, courtesy of Leonard J Matthews via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Thawing permafrost: Is it a ticking timebomb?

July 8, 2024 By EarthWise Leave a Comment

Permafrost covers about a quarter of the landmass in the Northern Hemisphere. It stores vast quantities of organic carbon in the form of dead plant matter. As long as it stays frozen, it is no threat to the climate. But as it thaws, microorganisms start breaking down that plant matter and large amounts of carbon are released into the atmosphere in the form of carbon dioxide and methane.

This process has often been described as a ticking timebomb for the climate. The theory is that once global warming reaches a certain level, the process will become self-amplifying setting off a catastrophic amount of warming. If that level was reached, it would be a tipping point in the changing climate.

An international research team from the Alfred Wegener Institute in Germany has extensively researched this hypothesis. Their conclusion is that within the permafrost, there are multiple geological, hydrological, and physical processes that are self-amplifying and, in some cases, irreversible. However, these processes act only locally or regionally. There is no evidence that some particular threshold in global warming could affect all permafrost and accelerate its thawing on a global level.

This research does not mean that Arctic permafrost is nothing to worry about. In fact, there are ways in which it is more worrisome. Because the permafrost is very heterogenous – meaning it is very different in different places – there will be numerous small, local tipping points that will be exceeded at different times and at different levels of warming. All of this will proceed in step with global warming, contributing to the overall worsening situation. There is no warming level below which permafrost thawing is not a problem.

**********

Web Links

Thawing permafrost: Not a climate tipping element, but nevertheless far-reaching impacts

Photo, posted January 24, 2014, courtesy of Brandt Meixell / USGS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Adirondack lakes becoming inhospitable for trout

February 15, 2024 By EarthWise Leave a Comment

A combination of the warming climate and the phenomenon of lake browning are making the bottom of most lakes in New York’s Adirondack Mountains unlivable for cold water fish – such as trout, salmon, and whitefish – in the summer.

Lake browning occurs when dissolved organic matter from forests turns the water tea-brown. Browning is the legacy of a century of acid rain and subsequently the fact that forest soils have suffered reduced capacity to absorb weak organic acids, leading to more dissolved plant matter flowing into lakes. Climate change has increased the frequency of extreme precipitation events and the length of growing seasons, leading to more runoff of organic matter.

Browner water traps more of the sun’s heat at the top of the lake and blocks the sun’s rays from reaching deeper. The result of the browning is lakes that are either too warm or too deoxygenated to support trout populations.

A study of 1,467 Adirondack lakes by Cornell University researchers found that only about 5% of them may continue to maintain water that is cold and oxygenated enough to support cold-water fish.

Deeper lakes fare much better because they have so much water that their oxygen is hard to deplete, but only 1% of all Adirondack lakes are deeper than 30 meters. Another 4% are very clear because the influx of cold water outpaces the expansion of low-oxygen zones and limits the effects of browning.

The study urges the protection of as many lakes as possible from species invasions, nutrient and salt pollution, and other forms of environmental degradation.

**********

Web Links

Most Adirondack lakes will likely become unsuitable for trout

Photo, posted July 17, 2011, courtesy of Lida via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Benefits Of No-Till Farming | Earth Wise

October 5, 2021 By EarthWise Leave a Comment

No-till farming is not new. In fact, it was used as far back as 10,000 years ago. But during the 18th and 19th centuries, tilling became popular because it allowed farmers to plant seeds more efficiently.

Tilling (or ploughing) is the process of preparing the soil for the cultivation of seeds by overturning the soil. The practice works animal manure, weeds, and other surface residues deep into the soil. While this all sounds like a good thing, it’s not.

Tilling removes plant matter and loosens the soil, leaving the soil bare and vulnerable to erosion. Tilling also displaces the millions of microbes and insects that form healthy soil biology. The long-term use of tilling can turn healthy soils into lifeless growing mediums dependent on chemical inputs.

But no-till farming also tends to rely on chemical inputs like glyphosate for weed control. According to a new study recently published in Agronomy Journal, researchers at Penn State have found that farmers using no-till farming can reduce herbicide use and still maintain crop yields by implementing integrated weed-management methods.

The research team conducted a nine-year experiment using herbicide-reduction practices in a crop rotation, which included soybean, corn, alfalfa, and canola. Some of the practices used to reduce herbicide inputs included seeding small-grain companion crops with perennials, and plowing once in six years to terminate the perennial forage rather than killing it with an herbicide.

While there was more weed biomass in the reduced herbicide treatment, the researchers found that the added weed pressure did not substantially affect crop yields.

It is possible to make agriculture more environmentally-friendly and sustainable without sacrificing productivity.

**********

Web Links

No-till production farmers can cut herbicide use, control weeds, protect profits

Photo, posted February 11, 2019, courtesy of the United Soybean Board via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Turning Atmospheric Carbon Into Useful Materials | Earth Wise

July 7, 2021 By EarthWise Leave a Comment

Plants have the ability to capture carbon dioxide from the atmosphere and incorporate it into leaves, fruits, wood, and other plant materials. This beneficial process is mostly temporary, as much of this carbon dioxide from plant matter ends up back in the atmosphere through decomposition, or even burning.

Researchers at the Salk Institute have proposed a more permanent fate for captured carbon by turning plant matter into a valuable industrial material called silicon carbide.

In a recent study published in the journal RSC Advances, Salk scientists transformed tobacco and corn husks into silicon carbide and evaluated and quantified the benefits of the process.

The researchers used a previously reported method to transform plant matter into silicon carbide in three stages and carefully tracked the carbon utilization at each stage.

Stage one is growing the plants. They used tobacco from seed, chosen for its short growing season. Then the harvested plants are frozen, ground into a powder, and treated with chemicals including a silicon-containing compound. Finally, the powder is subjected to a high-temperature process resulting in the production of silicon carbide.

Their analysis showed that much of the carbon sequestered by growing the plants could be preserved through the full process and the amount of energy required for the production of the silicon carbide (mostly from the high-temperature process) is comparable to current manufacturing processes for the material.

Permanently sequestering carbon from agricultural waste products by incorporating it into a valuable industrial material would be a valuable addition to strategies for reducing greenhouse gases in the atmosphere.

**********

Web Links

Transforming Atmospheric Carbon Into Industrially Useful Materials

Photo, posted August 3, 2013, courtesy of AJ Garrison via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Liana Vines And Carbon

May 25, 2017 By EarthWise

Liana vines are long-stemmed, woody vines that are rooted in the soil at ground level and use trees or other means of vertical support to climb up to the canopy to gain access to sunlight. There are numerous varieties from many plant families. And, for reasons that are not entirely clear, their abundance has doubled in recent decades.