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How the World’s Most Fertile Soil Can Help Reverse Climate Change
Feeding more than 7 billion people with minimal environmental and climate impacts is no small feat. That parts of the world are plagued by obesity while starvation is rampant elsewhere shows part of the problem revolves around distribution and social equity. But agricultural methods pose some of the biggest challenges.
Over the past half century, the world has moved increasingly to industrial agriculture—attempting to maximize efficiency through massive, often inhumane livestock operations; turning huge swaths of land over to monocrops requiring liberal use of fertilizers, pesticides and genetic modification; and reliance on fossil fuel-consuming machinery and underpaid migrant workers. This has contributed to increased greenhouse gas emissions; loss of forests and wetlands that prevent climate change by storing carbon; pollution from runoff and pesticides; antibiotic and pesticide resistance; reduced biodiversity; and soil degradation, erosion and loss.
One promising development is the renewed interest in a soil-building method from the distant past called "dark earth" or "terra preta," which involves mixing biochar with organic materials to create humus-rich soil that stores large amounts of carbon.
The "solution" offered by many experts is to double down on industrial agriculture and genetic modification. But doing so ignores how natural systems function and interact and assumes we can do better. History shows such hubris often leads to unexpected negative results. Others are attempting to understand how to work within nature's systems, using agroecological methods.
One promising development is the renewed interest in a soil-building method from the distant past called "dark earth" or "terra preta," which involves mixing biochar with organic materials to create humus-rich soil that stores large amounts of carbon. In the book Terra Preta: How the World's Most Fertile Soil Can Help Reverse Climate Change and Reduce World Hunger, Ute Scheub and co-authors claim increasing the humus content of soils worldwide by 10 percent within the next 50 years could reduce atmospheric CO2 concentrations to pre-industrial levels.
Dark earth's benefit to climate is just one of its many exciting possibilities. It also enhances soils so they produce higher yields, helps retain water and prevents erosion. It's more alive with biodiverse micro-organisms, making it easier for crops to adapt to changing conditions. And it's a good way to recycle nutrient-rich food scraps, plants wastes and even human and animal urine and feces, rather than allowing them to pollute soil, water and air through burning and runoff.
Biochar is a form of charcoal made via pyrolysis—heating organic wastes in a low-oxygen environment. According to Scheub, "If you pyrolyze organic wastes, up to 50 percent of the carbon, which plants have extracted from the atmosphere in the form of carbon dioxide, is converted into highly stable carbon, which can persist in soils for thousands of years." As well as carbon, biochar retains nutrients like nitrogen and phosphorous and because it's porous, adding it to soils and compost helps them store nutrients and water.
Western scientists first studied terra preta in 1874 when Canadian-born Cornell University professor Charles Hartt and his team found patches of dark, fertile soils, several meters deep, along parts of South America's Amazon River where earth is normally low in nutrients and organic matter. Later archeological research determined the soils were created by human communities up to 5,000 years ago.
Scientists have since shed more light on the technique. Because the ancient practice is still employed in Liberia and Ghana, Africa, scientists from Sussex, Cornell and other universities were recently able to compare dark earth to soils nearby where the technique isn't used. They found dark earth contained 200 to 300 percent more organic carbon and can support "far more intensive farming."
Cornell University lead author Dawit Solomon was surprised that "isolated indigenous communities living far apart in distance and time" achieved similar results unknown to modern agriculturalists. "This valuable strategy to improve soil fertility while also contributing to climate-change mitigation and adaptation in Africa could become an important component of the global climate-smart agricultural management strategy to achieve food security," he said.
Scheub and her co-authors say the technique can be used on any scale, from home and community gardens to large farms. Terra Preta includes instructions for creating biochar and enhanced soils, but cautions that organic wastes should be used rather than valuable forest products.
Dark earth won't solve all our climate problems, but combined with reducing fossil fuel use, it could make a huge difference while addressing many agriculture, food security and hunger issues.
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As a growing number of states move to pass laws that would criminalize pipeline protests and hit demonstrators with years in prison, an audio recording obtained by The Intercept showed a representative of a powerful oil and gas lobbying group bragging about the industry's success in crafting anti-protest legislation behind closed doors.
Speaking during a conference in Washington, DC in June, Derrick Morgan, senior vice president for federal and regulatory affairs at the American Fuel & Petrochemical Manufacturers (AFPM), touted "model legislation" that states across the nation have passed in recent months.
AFPM represents a number of major fossil fuel giants, including Chevron, Koch Industries and ExxonMobil.
"We've seen a lot of success at the state level, particularly starting with Oklahoma in 2017," said Morgan, citing Dakota Access Pipeline protests as the motivation behind the aggressive lobbying effort. "We're up to nine states that have passed laws that are substantially close to the model policy that you have in your packet."
Big Oil is now using its political power to try and criminalize protests of oil & gas infrastructure.— Friends of the Earth (@foe_us) August 19, 2019
"This legislation has potential to punish public participation and mischaracterize advocacy protected by the First Amendment."https://t.co/bmiHjONEhy
The audio recording comes just months after Texas Gov. Greg Abbott signed into law legislation that would punish anti-pipeline demonstrators with up to 10 years in prison, a move environmentalists condemned as a flagrant attack on free expression.
"Big Oil is hijacking our legislative system," Dallas Goldtooth of the Indigenous Environmental Network said after the Texas Senate passed the bill in May.
As The Intercept's Lee Fang reported Monday, the model legislation Morgan cited in his remarks "has been introduced in various forms in 22 states and passed in ... Texas, Louisiana, Oklahoma, Tennessee, Missouri, Indiana, Iowa, South Dakota, and North Dakota."
"The AFPM lobbyist also boasted that the template legislation has enjoyed bipartisan support," according to Fang. "In Louisiana, Democratic Gov. John Bel Edwards signed the version of the bill there, which is being challenged by the Center for Constitutional Rights. Even in Illinois, Morgan noted, 'We almost got that across the finish line in a very Democratic-dominated legislature.' The bill did not pass as it got pushed aside over time constraints at the end of the legislative session."
Many of the state bills restricting the right to protest have been "drafted by companies and passed through groups like ALEC, the secretive group of corporate lobbyists trying to rewrite state laws to benefit corporations over people." @greenpeaceusa https://t.co/ZxpTjWdrwT— Stand Up To ALEC (@StandUpToALEC) May 6, 2019
Reposted with permission from our media associate Common Dreams.