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The problem of mountain lions

May 5, 2025 By EarthWise Leave a Comment

Mountain lions – also known as pumas, cougars, and even sometimes panthers – are the most widely distributed wild land mammal in the world. They are found from Canada to South America. There are an estimated 30,000 mountain lions in the United States, mostly in the West, but there are also mountain lions from the Midwest to the East Coast.

Unlike wolves or grizzly bears, mountain lions are not managed by the federal government; they are managed by states and state regulations vary greatly. In some places, hunting mountain lions is banned completely; in other places, it is always open season.

As more people encroach on wild land – building homes and small farms, as well as hiking and biking – the numbers of encounters between people and mountain lions are increasing. And when mountain lions lose their fear of people, there is trouble.

Since 1890, there have been at least 32 fatal mountain lion attacks on humans and more than 170 non-fatal attacks. California has seen the most attacks in the last 40 years with 22 people injured and four killed. Despite this, Californians passed a ballot initiative in 1990 that bans all hunting of mountain lions.

There are strategies to reduce habituation and instill fear of humans in mountain lions. One is called “tree-and-free” that uses dogs to chase mountain lions up trees. But there are opponents of this and other measures employed.

The fact is that there are simply too many mountain lions living in close proximity to humans and peaceful coexistence is very difficult to achieve. Places where hunting lions is permitted have few problems with them, but that is not a solution that is acceptable in many places. It’s a difficult problem.

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Deadly Encounter: Mountain Lion Attacks Spark Controversy

Photo, posted March 26, 2013, courtesy of the USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A better way to extract lithium

December 10, 2024 By EarthWise Leave a Comment

Lithium is the critical component in the batteries that power phones and computers, electric cars, and the systems that store energy generated by solar and wind farms. Lithium is not particularly rare, but it is difficult and often environmentally harmful to extract from where it is found.

Traditional ore sources are increasingly difficult and expensive to mine. The largest known deposits of lithium are in natural brines – the salty water found in geothermal environments. These brines also contain other ions like sodium, potassium, magnesium, and calcium, and efficiently separating out the lithium is extremely challenging.

Traditional separation techniques consume large amounts of energy and produce chemical waste, particularly hazardous chlorine gas. These techniques typically suffer from poor selectivity; that is, the process is interfered with by the other ions present in natural brines.

A team of researchers at Rice University has developed a three-chamber electrochemical reactor that improves the selectivity and efficiency of lithium extraction from brines. The middle chamber of the reactor contains a specialized membrane that acts as a barrier to chloride ions, preventing them from getting to the electrode area where they can form chlorine gas.

The new reactor has achieved a lithium purity rate of 97.5%, which means the setup can effectively separate lithium from other ions in the brine and allow the production of high-quality lithium hydroxide, the key material for battery manufacturing.

The Rice University reactor design has the potential to be a game changer for lithium extraction from geothermal brines.

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‘Game changer’ in lithium extraction: Rice researchers develop novel electrochemical reactor

Photo, posted October 21, 2023, courtesy of Simaron via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Mining extinct volcanoes

December 2, 2024 By EarthWise Leave a Comment

Rare earth elements are a group of 17 elements that are used to improve the performance, efficiency, and durability of a wide range of products. More than 200 products across a diverse set of applications make use of rare earth elements. Although the amount of rare earth used in a particular product may not be very much of its weight, volume, or monetary value, it may often be necessary for the device even to function. Rare earth elements react with other elements to form compounds that are essential because of their specific chemical behaviors.

Rare earth elements are not actually rare; in fact, they are fairly common. But they are mostly not found in their pure form and are generally difficult to refine. China accounts for more than 90% of global production of rare earth elements and this represents a strategic problem for the rest of the world.

New research by scientists from the Australian National University has found that some extinct volcanoes, which have not erupted for thousands or even millions of years, may be rich sources of rare earth elements. Furthermore, those elements may be easier to extract than the ones from other sources because the iron-rich magma that formed the volcanoes could be up to 100 times more efficient at concentrating rare-earths than magma found in active volcanoes today.

The clean tech industry uses rare earths for wind turbines, solar panels, and electric cars. The demand for rare earths may grow fivefold by the end of this decade. Relying on just one country for the world’s supply is a major concern. There are ancient volcanoes all over the planet and they may represent a solution to a global problem.

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Extinct Volcanoes Could Be Source of Key Metals Needed for Clean Tech

Photo, posted June 6, 2020, courtesy of Dennis Jarvis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Big Food and greenhouse gas emissions

October 29, 2024 By EarthWise Leave a Comment

The global food system is responsible for as much as 40% of human-generated greenhouse gas emissions. The investor advocacy group Ceres has tracked whether the 50 largest North American food and agriculture companies have set targets to lower their emissions and whether doing so has actually resulted in lower emissions.

The emissions from food and agriculture companies are grouped into three so-called scopes. Scope 1 are emissions from a company’s direct operations. Scope 2 are emissions from its energy use. Scope 3 are emissions from a company’s supply chain: from the farmers who grow crops, raise cattle, and otherwise provide necessary items for a company’s final products. In the food industry, the scope 3 category is responsible for about 90% of overall emissions.

Of the 50 food companies studied, 23 reduced their scope 1 and scope 2 emissions over the past 2 years, but only 12 reduced their scope 3 emissions. Companies have more control over their scope 1 and scope 2 emissions.

Reducing scope 3 emissions is more difficult. And most companies haven’t set scope 3 reduction targets.

The findings of the study suggest that reducing scope 3 emissions is especially difficult for companies whose supply chains are linked to carbon-intensive commodities, like meat, or crops linked to deforestation or land-use change, both of which result in increased emissions.

In March, the Securities and Exchange Commission finalized rules requiring companies to disclose their climate risk to regulators, increasing the visibility of the food industry emissions issue.

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North America’s Biggest Food Companies Are Struggling to Lower Their Greenhouse Gas Emissions

Photo, posted October 13, 2011, courtesy of the United Soybean Board via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A dangerous invasive species

August 28, 2024 By EarthWise Leave a Comment

Weeds are the bane of every gardener’s existence. They pop up, uncontrolled and unwelcome, and must be tediously managed time and time again. But in some cases, weeds are more than just a nuisance. Some are a public health hazard.

Meet giant hogweed. Native to Europe’s Caucasus Mountains, giant hogweed belongs to the carrot family. The plant resembles Queen Anne’s Lace – on steroids. Giant hogweed can grow up to 15 feet tall with three inch stems, five-foot-wide leaves, and an umbrella-like canopy of white flowers.

Botanists brought giant hogweed to England as an ornamental plant in the 1890s. It made its way to the U.S. via horticultural channels. In fact, one of the first specimens was planted in a Victorian garden near Rochester, NY.

As with most invasive plants, it quietly escaped cultivation. In the U.S., giant hogweed can be found in New England, the Mid-Atlantic Region, and the Northwest, with plants preferring moist habitat near roadside ditches and stream banks.

While a seemingly innocent flowering plant, giant hogweed is actually one of the most hazardous plants in the U.S. Brushing against or breaking the plant releases sap that, when combined with sunlight and moisture, can cause severe burn-like lesions, blistering sores, and purplish or blackened scars. Getting sap in your eyes can result in temporary or even permanent blindness.

With each plant dropping up to 120,000 seeds, it’s no surprise that giant hogweed is proving difficult to eradicate.

If you suspect giant hogweed is growing near you, photograph the plant from a safe distance and report the sighting to local environmental authorities.

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Plant Pest Risk Assessment for Giant Hogweed

Giant Hogweed

Photo, posted March 22, 2021, courtesy of Scottish Invasive Species Initiative via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Ending plastic separation anxiety

December 27, 2023 By EarthWise Leave a Comment

Petroleum-based plastics are one of the biggest environmental problems we face. They mostly end up in landfills – or worse, in the oceans and elsewhere in the environment – and they basically don’t decompose over time. Bio-based plastics were invented to help solve the plastic waste crisis. These materials do break down in the environment providing a potential solution to the problem. But it turns out that they can actually make plastic waste management even more challenging.

The problem is that bioplastics look and feel so similar to conventional plastics that they get mixed in with the petroleum-based plastics rather than ending up in composters, where they can break down as designed.

Mixtures of conventional and bioplastics end up in recycling streams where they get shredded and melted down, resulting in materials that are of very poor quality for making functional products. The only solution is to try to separate the different plastics at recycling facilities, which is difficult and expensive to do.

Scientists at Lawrence Berkeley National Laboratory, the Joint BioEnergy Institute, and the incubator company X have invented a simple “one pot” process to break down mixtures of different types of plastic using naturally derived salt solutions and specialized microbes and then produce a new type of biodegradable polymer that can be made into fresh commodity products.

The team is experimenting with various catalysts to find the optimum way to break down polymers at the lowest cost and are modeling how their processes can work at the large scales of real-world recycling facilities. Chemical recycling of plastics is a hot topic but has been difficult to make happen economically at the commercial scale.

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Putting an End to Plastic Separation Anxiety

Photo, posted November 28, 2016, courtesy of Leonard J Matthews via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Актуальная ссылка на Мега сайт обеспечивает удобный и быстрый доступ к площадке.

Better Zinc Batteries | Earth Wise

May 17, 2023 By EarthWise Leave a Comment

The rapid growth of wind and solar power continues to drive a global quest for new battery technologies that can be used to store the energy generated by these sources when the sun isn’t shining, and the wind isn’t blowing.

For the most part, current battery energy storage systems use lithium-ion batteries – the same sort of batteries found in cellphones and electric vehicles. There are many other battery chemistries, but they mostly have shortcomings in performance, economy, or longevity.

Batteries store electricity in the form of chemical energy and chemical reactions convert that energy into electrical energy. Every battery has two electrodes: the anode, from which electrons flow into external circuits, and the cathode, which receives electrons from the external circuit. The electrolyte is the chemical medium through which the electrons flow.

One technology that has great potential is zinc-based batteries. Zinc itself is a metal that is safe and abundant. Batteries based on it are energy dense. However, zinc batteries have faced the challenge of having a short cycle life. The batteries end up plating zinc on their anodes and battery performance degrades.

A team of researchers at Oregon State University and three other universities have recently developed a new electrolyte for zinc batteries that raises the efficiency of the zinc metal anode to nearly 100% – actually slightly better than lithium-ion batteries.

Zinc batteries have a number of potential advantages over lithium-ion. The new hybrid electrolyte developed by the researchers is non-flammable, cost-effective, and has low environmental impact. Lithium-ion batteries rely on the supplies of relatively rare metals that are often difficult and environmentally harmful to obtain.

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Researchers develop electrolyte enabling high efficiency of safe, sustainable zinc batteries

Photo, posted May 13, 2017, courtesy of Jeanne Menjoulet via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Solar Cell Greenhouses | Earth Wise

April 21, 2021 By EarthWise Leave a Comment

A recent study at North Carolina State University has shown that it can be feasible to use see-through solar panels in greenhouses to generate electricity. The idea is to use semi-transparent solar panels on greenhouses that allow some of the light to get in for the plants to grow while making the greenhouses energy neutral or even allowing them to generate more power than they use.

The question is how the semi-transparent solar panels might affect greenhouse crops. To investigate this issue, researchers grew crops of red leaf lettuce from seed to full maturity under a standard set of growing conditions – temperature, water, fertilizer, and CO2 concentration – but varied the light they get.

A control group was exposed to the full spectrum of white light while three experimental groups were exposed to light through different types of filters that absorbed the particular wavelengths of light that would be absorbed by different types of semitransparent solar cells.

The researchers paid close attention to characteristics of the lettuce that are important to growers, grocers, and consumers: general appearance, leaf number, leaf size, and weight. The results were that the lettuce produced using all three kinds of filtered light was essentially identical to that produced in the control group. Further research is underway looking at how harvesting various wavelengths of light affects biological processes for lettuces, tomatoes, and other crops.

Getting growers to use solar-powered greenhouses would be very difficult if doing so would result in a loss of productivity. But given these experimental results, it appears as though the decision will boil down to a simple economic argument about whether the investment in new greenhouse technology would be offset by energy production and its resultant savings.

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Study Finds Plants Would Grow Well in Solar Cell Greenhouses

Photo, posted April 8, 2008, courtesy of Brian Boucheron via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.