from the world's big
Carbon nanotubes embedded in leaves detect chemical signals that are produced when a plant is damaged.
Researchers evaluated the best and worst ways to remove greenhouse gases from the atmosphere in a recent report.
- A recent report from International Institute for Applied Systems Science evaluated six land-based methods for removing greenhouse gases from the atmosphere.
- Though they concluded that every technique would be a net positive for the world, some were riskier or costlier than others.
- Among the safest, cheapest, and overall best approaches were restoring the wetlands and soil carbon sequestration.
In 2016, the Paris Climate Agreement set out the ambitious goal of limiting the rise in global temperature to below 2°C above its preindustrial levels, preferably to 1.5°C. These numbers might seem small, but the amount of energy needed to transform the entire world's average temperature is tremendous, and so too are its effects. If, for instance, the global temperature blasts past that 2°C mark and reaches 4°C, then nearly all of the U.S. will turn into an uninhabitable desert.
But focusing too much on the doom-and-gloom that climate change discussions so often revolve around can be pretty exhausting. So, let's focus instead on possible solutions. If we're to stay below 2°C, we'll need to deploy a multifaceted strategy. Part of that has to be finding ways to remove the greenhouse gases already in our atmosphere.
Recently, researchers at the International Institute for Applied Systems Science looked at the top six land-based methods for sucking greenhouse gases out of the atmosphere to evaluate their costs, their benefits, and which might be our best options going forward. While some of them are more risky or higher cost than others, all of them were found to contribute in some way and to effectively remove greenhouse gases from out of atmosphere.
1. Afforestation and reforestation
Between 1990 and 2015, the world lost 290 million hectares of forest. Restoring these depleted reserves (reforestation) and planting in previously un-forested areas (afforestation) is a fairly simple, common-sense approach to fighting climate change. Trees suck CO2 out of the air and store it in their timber — not only that, but they also contribute to food production, help to regulate freshwater, offer habitats to animals, and provide jobs and recreation among other benefits.
On the other hand, afforestation and reforestation require a lot of water usage and take up land that could otherwise be used for farming. Despite this, the researchers estimated that this strategy could remove between 0.5 to 7 gigatons (that's a billion tons) of CO2 from the atmosphere. To put that into context, one estimate provided by Carbon Brief suggests that human beings have released 1,374 gigatons of CO2 into the atmosphere since the Industrial Revolution. We don't have to get rid of all of this extra CO2, fortunately; just enough to keep warming within acceptable bounds.
2. Wetland restoration
Wetlands might seem like an odd candidate for being one of the most beneficial features of the planet, but they have the potential to scrub another 2.7 gigatons of CO2 from the air. In fact, although wetlands cover 9 percent of the planet, they're estimated to deliver 23 percent of the total value offered by the globe's ecosystems.
For instance, wetlands are the best regulators of water resources out there—they're even sometimes intentionally developed near sewage plants to help filter out pollutants. They also provide habitats for keystone species, can help to produce certain crops (e.g., rice or cranberries), and are extremely resilient to rising sea levels.
Although they tend to release some methane, the amount of CO2 they suck up is well worth it. Regrettably, however, half of the globe's wetlands have been lost, making their restoration a top priority. In addition to being a cheap venture, the researchers also identified virtually no downsides to restoring wetlands.
3. Soil carbon sequestration
Like wetland restoration, soil carbon sequestration — storing carbon in the soil over the long term — presents few downsides. This can take place through a variety of mechanisms, the biggest one being the photosynthesis of plants. But smart crop management, like rotating crops, planting perennial crops (those that don't need to be replanted every year), and so on, can increase how much carbon is stored in the soil. So too can optimizing fertilizer usage, tilling less intensely, improving water management, and many other techniques. Implementing these techniques could result in a reduction of between 2 and 5 gigatons of CO2.
By farming with the conscious goal of sequestering more carbon in the soil, we also gain the benefit of having more useful soil for use in building materials, pharmaceuticals, electronics, and other industrial applications. Plus, it helps to prevent erosion, preserves the landscape, and increases crop yields.
Flickr user Oregon Department of Forestry
Biochar is the result of biomass pyrolysis; simply put, it's charcoal. When biomass is burned in a low- or no-oxygen environment, it becomes carbonized, locking that carbon into the material and preventing its transference to the atmosphere. Biochar stores carbon in a long-term, durable fashion. Typically, biochar is distributed in soil, where it can help improve food production and balance the pH of acidic soil. Microorganisms in soils also emit nitrous oxide, another greenhouse gas, but adding small amounts of biochar significantly reduces these emissions, along with other greenhouse gases other than CO2. Plus, producing biochar can also generate electricity.
However, biochar production has to be done carefully. If produced without following clean guidelines, biochar can actually release more greenhouse gases into the atmosphere. But if done correctly, producing biochar could reduce greenhouse gases by up to 2 gigatons of CO2 a year.
5. Terrestrial enhanced weathering
A considerable amount of chemistry is slowly but consistently being conducted beneath our feet. In particular, weathering plays an important role in soil chemistry. As the soil's minerals break down over time, they release nutrients and form secondary minerals, like clay. We can improve this process and encourage desirable soil chemistry by adding crushed silicate rocks rich in calcium and magnesium and low in metal ions like nickel or chromium. Basalt, for instance, would be a good candidate.
Doing so could reduce soil acidity and encourage the transformation of CO2 into bicarbonate ions, or HCO3-. As an added benefit, run-off HCO3- could increase ocean alkalinity, making the ocean more resistant to pH changes. Although it would have some positive effect, the researchers noted that field-scale assessments of this technique's interactions with other approaches — like reforestation — would be necessary to determine exactly how much terrestrial enhanced weathering could contribute to reducing greenhouse gas emissions.
6. Bioenergy carbon capture and storage (BECCS)
An engineer walks through the Bailey Bioenergy Facility in Washington, D.C.
Katherine Frey/The Washington Post via Getty Images
The use of BECCS is something of a one-two punch; it provides energy, avoiding the need to use fossil fuels, and as feedstocks grow for later use as fuel, they suck CO2 out of the atmosphere. Plants like switchgrass or giant reedgrass make for excellent BECCS feedstocks.
Generally, regular bioenergy is a carbon-zero product, since the fuel sequesters CO2 as it grows and releases CO2 as it's burned for energy. But incorporating carbon capture and storage (CCS) technology in this process results in negative emissions. This beats adding CCS technology to fossil fuel processes, since burning fossil fuels starts off by adding emissions to the atmosphere — existing CCS tech can therefore only reduce fossil fuel emissions, rather than turning them negative as is the case with bioenergy.
If BECCS were implemented at a large scale by the year 2100, it could remove 15 gigatons of CO2 per year. However, doing so would be expensive, and the land taken up to grow bioenergy feedstocks could be used instead to grow food. It would also require a greater use of fertilizers and would require a good amount of water to grow.
With the exception of wetland restoration and soil carbon sequestration, all of these approaches for greenhouse gas removal present some kind of downside that we would need to mitigate. The most challenging approaches would be afforestation/reforestation, BECCS, and biochar production, primarily due to their use of land that could otherwise grow food and their water requirements.
However, the researchers found that all of these methods for greenhouse gas removal would not only reduce greenhouse gases in the atmosphere, but, on balance, they would also make our lives better, either by creating jobs, reducing pollution, contributing food, promoting ecological diversity, or other ancillary benefits. Combating climate change is often presented as a costly venture, but in reality, it's more of an investment. By assessing the costs and benefits of approaches such as these six, we can get a better picture of what our return will be.
When these particles are eaten by earthworms, the results are not good.
- New research from Anglia Ruskin University states that microplastics in soil are causing earthworms to lose weight.
- Soil affected by microplastics produces less crop yield due to less productive earthworms and lower pH levels.
- If this trend continues, our entire agricultural system could be compromised.
Microplastics are everywhere | Sarah Dudas | TEDxBinghamtonUniversity<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="a0f0c0566b5d3f51fba4540d77bb3b5e"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/jjsrmFUmyh4?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p>We often mistake broad names for processes as "extra." For example, dark matter, which represents 85 percent of all matter in the universe, is believed to non-baryonic, yet physicists recognize that it could be comprised of subatomic particles we haven't yet discovered. The universe isn't know for creating filler; usually, our own ignorance is the culprit.</p><p>"Dirt" and "soil," to non-farmers at least, are often treated as an earth layer; referencing it is often in the negative, as when a parent scolds a child for "playing in the dirt." But soil is a process, living and organic, dependent on decaying and dead matter constantly being churned through (by earthworms, for example) and recycled. </p><p>Soil is one of the major reasons that America has become a global power. Our fields supply an incredible amount of food for the planet. By contrast, China, with its billion-plus population to feed, struggles to produce adequate amounts of nutrition due to less fertile soil. This is, in fact, one of the undiscussed underpinnings of the current "trade war."</p><p>Damaged soil destroys not only ecosystems, but societies as well. When famers try to increase crop yield by introducing plastic mulches and irrigation, they're unknowingly polluting the soil with tons of microplastic particles. These particles are then ingested by earthworms (among other animals), causing them to lose weight.<span></span></p><p>The research team chose the most important grass grown in temperate regions; in grassland ecosystems ryegrass is abundant. A variety of ecosystems were used, some with added microplastics, one control without. Earthworms were most affected by HDPE microplastics, though any of the added particles made life worse for the worms.</p>
A view of the Schiavonea beach with microplastics, transported by the Ionian sea during the last sea storm.
Photo by Alfonso Di Vincenzo/KONTROLAB /LightRocket via Getty Images<p>Soil is generally low in nutrient value, meaning that worms have to eat and pass a lot of it for their existence. The team compares the results to aquatic environments, in which the digestive tracts of fish, like worms, are obstructed and worn away. The consumption of microplastic particles stunts their growth while compromising the survival of the organism.<br></p><p>Beyond worms, the particles (especially HDPE) decrease soil pH. This directly affects the diversity of organisms living there. As with the human microbiome, in which a diverse population of bacteria is healthiest, soil pays a steep price when diversity drops. </p><p>These particles don't remain in the soil; they end up, in some cases, on your plate. The team writes, </p><p style="margin-left: 20px;">"In agricultural settings, such effects may have implications for the production and quality of crop plants, by directly affecting plant development and altering the soil environment in which they are produced as well as having potential implications for human health through the accumulation of microplastics and harmful compounds in the tissues of plants."</p><p>All plastics are biodegradable. The problem is, some take weeks to mineralize while others hang around for millions of years. Until we implement broad solutions that implement a shelf life for plastics, these particles aren't going anywhere—except inside of our digestive tracts, eventually. As with worms, such news doesn't look good for the health of our species. </p><p>--</p><p><em>Stay in touch with Derek on <a href="http://www.twitter.com/derekberes" target="_blank">Twitter</a> and <a href="https://www.facebook.com/DerekBeresdotcom" target="_blank">Facebook</a>.</em></p>
How do you convince people to break the habit of a lifetime?
To keep global heating below 2°C, the world's appetite for meat must change.
The face of protein in the 21st century?<h2>Nudge, nudge</h2><p>Nudging people away from meat could include <a href="https://www.standard.co.uk/futurelondon/health/public-health-experts-supermarket-holborn-nudge-a4199071.html" target="_blank">changing the layout of places where food is bought or eaten</a>, or designing menus so that vegetarian options are given equal or greater prominence than meat dishes.</p><p>But the complexity of food choice means that these may not be as effective outside experiments. In the real world, what people choose to eat is driven by a whole host of factors including the smell or texture of food and cultural norms.</p><p>Nudges tend to work by targeting unconscious thoughts and behaviours. Many of our food choices <a href="https://journals.sagepub.com/doi/abs/10.1177/0013916506295573" target="_blank">tend to rely on this</a>, through <a href="https://www.sciencedirect.com/science/article/pii/S0195666311005265" target="_blank">habit</a> or <a href="https://www.sciencedirect.com/science/article/pii/S0195666310004940#bib0070" target="_blank">convenience</a>. You're more likely to pick the option you've tried before and enjoyed, or that you know is easy to prepare, without carefully thinking about it. People remain reluctant to buy food that their partners or children may reject. So attitudes to meat and plant-based substitutes still need addressing to alter eating behaviour.</p><p>One area that shows particular promise is targeting people at specific stages in their lives. We found that older people would still want to eat foods which they had eaten as children. If children are given access to more plant-based proteins – and educated on their benefits for health and the environment – they might remain a valued component of their diet throughout their lives.<br></p><p>There are reasons to be optimistic that the dietary changes needed to limit global heating are achievable. Attitudes towards meat consumption are already changing, and there are plenty of options to try and encourage more people to pursue a diet that's better for them and the planet.<img alt="The Conversation" src="https://counter.theconversation.com/content/121001/count.gif?distributor=republish-lightbox-basic"></p><p><a href="https://theconversation.com/profiles/david-mcbey-787558" target="_blank">David McBey</a>, Project Co-ordinator and Sociologist, <em><a href="http://theconversation.com/institutions/university-of-aberdeen-962" target="_blank">University of Aberdeen</a></em> and <a href="https://theconversation.com/profiles/alex-johnstone-456670" target="_blank">Alex Johnstone</a>, Personal Chair in Nutrition, The Rowett Institute, <em><a href="http://theconversation.com/institutions/university-of-aberdeen-962" target="_blank">University of Aberdeen</a>.</em></p><p>This article is republished from <a href="http://theconversation.com/" target="_blank">The Conversation</a> under a Creative Commons license. Read the <a href="https://theconversation.com/nudging-meat-off-the-menu-121001" target="_blank">original article</a>.</p>
Even before publication, health agencies were asking the journal not to publish the research.
- A new study in the Annals of Internal Medicine found little correlation between red meat consumption and health problems.
- A number of organizations immediately contested the evidence, claiming it to be based on an irrelevant system of analysis.
- Beef and dairy production is one of the leading drivers of climate change, forcing humans to weigh personal health against the environment.
Gut Bacteria and Red Meat: Highlight from Cancer and Diet<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="71072a183e860d9d8b97754f5a71de8c"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/wdv8JIIjL6s?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p>Nutrition science is tricky. Not only do self-endowed "life coaches" and fitness trainers not certified in nutrition offer unsolicited advice, actual scientific bodies find it hard to come to conclusions. One of the biggest issues: It's nearly impossible to isolate macronutrients or entire classes of food given their interactions with all the other food you consume. A burger doesn't have the same effect on your body as a burger with mayonnaise on a bun; whether you drink water or soda to accompany that meal matters too. <br></p><p>The main contention comes from the type of analysis the researchers used. As Harvard nutrition scientist, Frank Hu, <a href="https://www.npr.org/sections/thesalt/2019/09/30/765722916/no-need-to-cut-back-on-red-meat-controversial-new-guidelines-lead-to-outrage" target="_blank">says</a>, the <a href="https://ktdrr.org/products/update/v1n5/dijkers_grade_ktupdatev1n5.pdf" target="_blank">GRADE</a> systematic approach was introduced for evaluating drug trials, not nutrition science. Alongside his colleagues, Hu <a href="https://www.hsph.harvard.edu/nutritionsource/2019/09/30/flawed-guidelines-red-processed-meat/" target="_blank">published an article</a> countering the results of the meta-analyses, coming to four conclusions:</p><ul><li>The new guidelines are not justified as they contradict the evidence generated from their own meta-analyses</li><li>The publication of these studies and the meat guidelines in a major medical journal is unfortunate because following the new guidelines may potentially harm individuals' health, public health, and planetary health</li><li>This is a prime example where one must look beyond the headlines and abstract conclusions</li><li>These studies should not change current recommendations on healthy and balanced eating patterns for the prevention of chronic diseases</li></ul>
Close-up of Impossible Whopper, a meat-free item using engineered, plant-protein based burger patty from food technology company Impossible, during a limited market test at a Burger King restaurant in the San Francisco Bay Area, Danville, California, June 26, 2019.
Photo by Smith Collection/Gado/Getty Images<p>As with many topics in American discourse, our diet has become polarized. Those that claim that humans were not designed to eat meat are ignorant of how our biology (and cultures) evolved. As primatologist Richard Wrangham <a href="https://www.amazon.com/Catching-Fire-Cooking-Made-Human/dp/1469298708" target="_blank">writes</a>, the greatest culinary advancement in history was fire. Cooking made nutrients available much more quickly—a burger on a grill is more nutritious than chewing on raw meat. And meat is something our ancestors definitively ate whenever they could.<br></p><p>What also doesn't help is a sentiment that has been batted around the holistic blogosphere: that meat is toxic. To be fair, growth hormones and factory farming have increased the potential for toxicity in our food supply. But meat itself is not inherently toxic to our digestive system. As Harvard paleoanthropologist, Daniel Lieberman, <a href="https://www.amazon.com/Story-Human-Body-Evolution-Disease/dp/030774180X" target="_blank" rel="noopener noreferrer">writes</a>, given our ancestors' adaptation to diverse climates, there is no "optimal diet." We ate what we could source. That said, meat consumption offered a particularly important boon to our biology.</p><p style="margin-left: 20px;">"By incorporating meat in the diet and relying more on food processing, early <em>Homo</em> was able to spend much less energy digesting its food and could thus devote more energy toward growing and paying for a larger brain." </p><p>Yet that doesn't mean we <em>need</em> to eat meat, at least not as much of it was we do. Beyond sating our biological impulse, industrial agriculture—specifically, <a href="http://www.fao.org/news/story/en/item/197623/icode/" target="_blank">beef and dairy production</a>—is one of the biggest drivers of climate change. Beef is extremely taxing on the environment, <a href="https://science.sciencemag.org/content/360/6392/987/tab-figures-data" target="_blank">much more so</a> than chicken or pork agriculture. </p><p>From a climate perspective, plant-based diets are less taxing, though you often run into the problem of nutrient loss due to monocropping. Plant-based burgers might be all the rage, but that also doesn't mean <a href="https://www.scientificamerican.com/article/is-the-vegan-impossible-burger-healthy-for-you/" target="_blank">they're healthy</a>, which brings into question whether or not it makes sense to sacrifice personal health for a perceived environmental gain. </p><p><span></span>An easy answer? Not here.</p><p><span></span>One thing is clear: The current rate of beef production is unsustainable. Whether or not 4.5 servings of red meat will increase your risk of cancer or heart disease might remain a source of contention. But a more important question remains: If reducing your meat intake is better for the environment (and therefore everyone's health), isn't that a wiser decision to make? </p><span></span><p>--</p><p><em>Stay in touch with Derek on <a href="http://www.twitter.com/derekberes" target="_blank">Twitter</a> and <a href="https://www.facebook.com/DerekBeresdotcom" target="_blank">Facebook</a>.</em></p>