plowing

Self-heating concrete

April 24, 2024 By EarthWise Leave a Comment

States in the colder parts of the country spend an estimated $2.3 billion a year on snow and ice removal as well as untold millions on repairing roadways damaged by winter weather. Researchers at Drexel University have been researching a way to extend the service life of concrete surfaces like roadways and to help them maintain a surface temperature above freezing during the winter.

Preventing freezing and thawing as temperatures go up and down and reducing the amount of plowing and salting is a desirable goal. The Drexel team has developed a cold-weather-resilient concrete mix that is capable of melting snow on its own using only the thermal energy in the environment and not requiring salt, shoveling, or heating systems.

The system uses low-temperature liquid paraffin that turns from its room-temperature liquid state into a solid when temperatures go down. Incorporating the liquid paraffin into concrete triggers heating when temperatures drop due to the energy released by the phase change.

Tests on slabs of the concrete on the Drexel campus over the past two years recorded 32 freeze-thaw events. The special slabs maintained a surface temperature between 42 and 55 degrees for up to 10 hours when air temperatures dipped below freezing.

The heating is enough to melt a couple of inches of snow at a rate of a quarter inch an hour. It’s not enough to melt a heavy snow event before plows are needed, but it can help deice road surfaces and increase transportation safety. And simply preventing the surface from freezing, thawing, and refreezing can go a long way towards preventing deterioration. It is promising research toward reducing an ongoing problem in colder climates.

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Drexel’s Self-Heating Concrete Is One Step Closer to Clearing Sidewalks Without Shoveling or Salting

Photo, posted March 16, 2024, courtesy of Ajay Suresh via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Healthy Soil Is Healthy For People | Earth Wise

March 30, 2022 By EarthWise Leave a Comment

A new study by researchers at the University of Washington looked at the impact of regenerative farming practices on the nutritional content of the food that is grown.

Regenerative agriculture involves farming practices that not only “do not harm” to the land but actually improve it by regenerating and revitalizing the soil. The practices focus on topsoil regeneration, increasing biodiversity, improving the water cycle, and enhancing ecosystem services. Examples are soil-building techniques that minimize plowing, the use of cover crops, and the planting of diverse crops rather than monocultures.

The study included 10 farms across the U.S. that followed soil-friendly practices for at least five years. The results were that the crops from those farms had a healthier nutritional profile than the same crops grown on neighboring, conventional farms. In particular, there was a boost in certain minerals, vitamins and phytochemicals that are beneficial to human health. Across the board, regenerative practices resulted in crops with more anti-inflammatory compounds and antioxidants.

The participating farms grew one acre of a test crop – peas, sorghum, corn, or soybeans – for comparison with the same crop grown on a neighboring farm using conventional agriculture. Analysis showed that the farms practicing regenerative agriculture had healthier soils, as measured by their organic matter – or carbon – content and by other tests.

Organic farms avoid chemical pesticides, but they operate with a variety of farming processes. Nonetheless, they have also been found to produce crops with higher levels of beneficial nutrients. The biology of the soil in which crops are grown is an important factor for human health. It isn’t just what we eat that matters; it is how we grow it.

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Farms following soil-friendly practices grow healthier food, study suggests

Photo, posted January 10, 2020, courtesy of Les 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.

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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.

Wild Pigs And The Environment | Earth Wise

September 3, 2021 By EarthWise Leave a Comment

There are millions of wild pigs in the world with the largest numbers in the United States and Australia but significant numbers in South America, Europe, and China. In the US, there are as many as 9 million feral swine living in 38 states. A conservative estimate indicates that they cause about $1.5 billion in property and agricultural damage each year in this country.

Researchers in Australia have studied the climate damage wild pigs are causing across five continents. According to the study, by uprooting carbon trapped in soil, wild pigs are releasing over 5 million tons of carbon dioxide annually, which is the equivalent of 1.1 million cars.

When soils are disturbed from humans plowing a field, or from wild animals uprooting, carbon is released into the atmosphere. According to the researchers, wild pigs are just like tractors plowing through fields, turning over soil to find food.

The study used predictive population models coupled with advanced mapping techniques to pinpoint the damage wild pigs are causing. According to the models, pigs are currently uprooting an area between 14,000 and 47,000 square miles, which is an enormous amount of land. The effects are not just on the health of the soil and on carbon emissions. This much damage also threatens biodiversity and food security.

Wild pigs are basically a human-caused problem, being either feral descendants of domestic swine, or hybrids of domestic swine and wild boars. Wild pigs are prolific and their numbers have been expanding rapidly Controlling their populations will require cooperation and collaboration across multiple jurisdictions.

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The climate impact of wild pigs greater than a million cars

Photo, posted July 1, 2017, courtesy of Shiva Shenoy via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Eco-Friendly Agriculture

October 21, 2019 By EarthWise Leave a Comment

Modern agriculture has steadily destroyed native grasslands, among other ecosystems. In fact, farming is one of the most ecologically destructive things that humans do. But we do have to eat. In response, there is a growing movement for agrarian reform, from grain farming on the prairie, to agroforestry, to raising livestock more sustainably. Efforts are accelerating to develop a kinder, gentler agriculture adapted to a changing world.

One such effort has come from the Land Institute, an organization in Kansas that works on natural systems agriculture, which seeks to retain the ecological stability of the prairie with its perennial seed plants along with a grain and seed yield comparable to that from annual crops.

After four decades of effort, the institute has introduced its first commercial grain, a trademarked variety called Kernza. Kernza is a domesticated perennial wild grass – a so-called intermediate wheatgrass – that has a long, slender head that resembles wheat seeds. People describe its taste as sweet and nutty. Kernza is already being made into a cereal called Honey Toasted Kernza by Cascadian Farms. Patagonia Provisions – a spin-off from the clothing company – is making beer from the new grain.

Although Kernza is already being grown and sold commercially, it is not yet ready for prime time. Last year, there were only about 1,000 acres in cultivation and the yield is only a third to a tenth of the yield of wheat.

Developing a sustainable perennial polyculture of edible plants would have major benefits such as not having to plow every year, plants developing large root systems that can reach water far beneath the surface and, without annual plowing, having soil carbon remain in the ground.

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With New Perennial Grain, a Step Forward for Eco-Friendly Agriculture

Photo courtesy of Cascadian Farms/General Mills.

Earth Wise is a production of WAMC Northeast Public Radio.