Agriculture

Subterms

    More stories

    • 75 Shares169 Views

      in Security

      Building a better indoor herb garden

      by

      Randall Briggs ’09, SM ’18 didn’t set out to build indoor gardens when he arrived at MIT. The winner of the 2010 2.007 robot competition class, he was excited to work on designing fighter planes one day.

      But in 2016, halfway through his studies for his master’s degree in mechanical engineering, Briggs’s father passed away unexpectedly. “It was a big blow to me. My motivation took a big hit, so it was hard for me to keep working on my research,” Briggs shares.

      Briggs ordered a home hydroponic garden in the hopes that growing herbs inside his apartment could bring him some positivity. “There is something healing about seeing something organic and beautiful grow and develop,” Briggs says.

      When the garden arrived, Briggs found that many aspects of the design fell short. The plants weren’t getting enough light because the LEDs were dispersing light throughout the room and not focusing it on the plants. “It’s just not very pleasing aesthetically when it’s, like, a fluorescent color of light, and it just fills your room,” Briggs says.

      He set forth to create a better indoor garden. Briggs turned his spare bedroom into a hydroponics lab, testing herbs growing under various lighting conditions and with different nutrient solutions. He read every book and article he could find on the subject. “The same seed pods that I had used in that cheap garden, when I moved them over to my garden, they grew way faster and way healthier and more fragrant and full of flavor,” he says.

      Working on this project became a daily source of joy for Briggs. “Every day when you come home, you want to see if it’s growing a little bit more or to see how they’re doing. I think that made me happy, too.”

      Briggs saw the potential for his garden to improve the well-being of others. “I thought if people had fresh herbs at home, they might be more inspired to cook for themselves instead of always just eating out, as it’s normally a lot healthier to cook your own food at home.”

      After much research and experimentation, GardenByte was born in 2017: a tabletop indoor herb garden that is nearly 3 feet wide with almost 2 feet of height for the plants to grow, which is quite a bit larger than most models on the market. With Briggs’s hydroponics technology, the plants grow three times faster than they would grow outdoors. His garden allows anyone to grow fresh herbs in a wide range of settings. And since plants have a longer shelf life than cut herbs, they also cut down on food waste.

      Briggs was determined to make something that grows plants well and is attractive in a variety of settings. The outer case is handcrafted from solid hardwood from a local Massachusetts lumber yard, ensuring both durability and a visually pleasing aesthetic that seamlessly integrates into any kitchen or restaurant setting. The light bar, crafted from a single piece of crystal-clear acrylic, maintains an unobtrusive and ethereal appearance. This choice complements the overall design while allowing the LED lights to emit a powerful simulation of full sunshine. To ensure a smooth transition from daytime growth to evening, four different types of LEDs were incorporated. Polymer lenses focus the light directly onto the plants, preventing any wastage or unnecessary light spillage in the room. A light and color sensor on top detect the lighting conditions in the room and automatically adjust the lighting in the garden to match, enhancing plant growth. The grid tray is designed to accommodate up to 39 plants at once, offering ample space for an array of herbs. To simplify plant care, the garden is connected to a mobile app that will allow you to care for your plants while you’re away.

      The herb garden contains computer numerical control (CNC) machined-aluminum parts, in contrast with the flimsier plastic most products use. The heat flow capacity of aluminum disperses the heat from all the LEDs and the aluminum grid tray helps keep it compact and thin but rigid, so users can lift the plants up without it bending.

      Briggs received his foundation in machining as an undergrad at the MIT Edgerton Center, where he was on the MIT Motorsports team and MIT Electric Vehicle Team. He learned how to use the CNC machines in the student machine shop at the Area 51 garage under the tutelage of Instructor Pat McAtamney and Briggs’s teammates.

      Building an electric motorcycle on the Electric Vehicle Team for the Isle of Man TT Race in 2011 helped prepare Briggs for creating a robust product for production. The race took place on city streets, raising the potential for deadly crashes. “When we were building that motorcycle, the head of our team, Lennon Rodgers, kept reiterating to us, ‘you got to think aircraft quality, like aircraft quality. This is actually a life-or-death project.’ Seeing the way that he led, and the way that he really set the bar for quality and for execution and kind of kept things moving, was really helpful for me.”

      “My hope in the future is to make a more mass-market version that’s a little bit cheaper and more available to everybody,” Briggs shares.

      The feedback from his first customers has all been positive. After delivering the product to a chef in Boston, Briggs says, “He told me that the whole first evening he was sitting at home with his boyfriend and he just kept staring at it, and he’s like, ‘it is so beautiful. It is so beautiful.’”

      “I feel like something that my dad taught me was that sometimes to do hard things, it does take hard work, and that it’s not always going to be exciting, necessarily,” Briggs shares. “It’s good to be inspired, it’s good to be passionate, but it’s not always going to get you through. And sometimes it’s just hard work that you got to press through the tough parts.” More

    • 175 Shares189 Views

      in Energy

      Accelerated climate action needed to sharply reduce current risks to life and life-support systems

      by

      Hottest day on record. Hottest month on record. Extreme marine heatwaves. Record-low Antarctic sea-ice.

      While El Niño is a short-term factor in this year’s record-breaking heat, human-caused climate change is the long-term driver. And as global warming edges closer to 1.5 degrees Celsius — the aspirational upper limit set in the Paris Agreement in 2015 — ushering in more intense and frequent heatwaves, floods, wildfires, and other climate extremes much sooner than many expected, current greenhouse gas emissions-reduction policies are far too weak to keep the planet from exceeding that threshold. In fact, on roughly one-third of days in 2023, the average global temperature was at least 1.5 C higher than pre-industrial levels. Faster and bolder action will be needed — from the in-progress United Nations Climate Change Conference (COP28) and beyond — to stabilize the climate and minimize risks to human (and nonhuman) lives and the life-support systems (e.g., food, water, shelter, and more) upon which they depend.

      Quantifying the risks posed by simply maintaining existing climate policies — and the benefits (i.e., avoided damages and costs) of accelerated climate action aligned with the 1.5 C goal — is the central task of the 2023 Global Change Outlook, recently released by the MIT Joint Program on the Science and Policy of Global Change.

      Based on a rigorous, integrated analysis of population and economic growth, technological change, Paris Agreement emissions-reduction pledges (Nationally Determined Contributions, or NDCs), geopolitical tensions, and other factors, the report presents the MIT Joint Program’s latest projections for the future of the earth’s energy, food, water, and climate systems, as well as prospects for achieving the Paris Agreement’s short- and long-term climate goals.

      The 2023 Global Change Outlook performs its risk-benefit analysis by focusing on two scenarios. The first, Current Trends, assumes that Paris Agreement NDCs are implemented through the year 2030, and maintained thereafter. While this scenario represents an unprecedented global commitment to limit greenhouse gas emissions, it neither stabilizes climate nor limits climate change. The second scenario, Accelerated Actions, extends from the Paris Agreement’s initial NDCs and aligns with its long-term goals. This scenario aims to limit and stabilize human-induced global climate warming to 1.5 C by the end of this century with at least a 50 percent probability. Uncertainty is quantified using 400-member ensembles of projections for each scenario.

      This year’s report also includes a visualization tool that enables a higher-resolution exploration of both scenarios.

      Energy

      Between 2020 and 2050, population and economic growth are projected to drive continued increases in energy needs and electrification. Successful achievement of current Paris Agreement pledges will reinforce a shift away from fossil fuels, but additional actions will be required to accelerate the energy transition needed to cap global warming at 1.5 C by 2100.

      During this 30-year period under the Current Trends scenario, the share of fossil fuels in the global energy mix drops from 80 percent to 70 percent. Variable renewable energy (wind and solar) is the fastest growing energy source with more than an 8.6-fold increase. In the Accelerated Actions scenario, the share of low-carbon energy sources grows from 20 percent to slightly more than 60 percent, a much faster growth rate than in the Current Trends scenario; wind and solar energy undergo more than a 13.3-fold increase.

      While the electric power sector is expected to successfully scale up (with electricity production increasing by 73 percent under Current Trends, and 87 percent under Accelerated Actions) to accommodate increased demand (particularly for variable renewables), other sectors face stiffer challenges in their efforts to decarbonize.

      “Due to a sizeable need for hydrocarbons in the form of liquid and gaseous fuels for sectors such as heavy-duty long-distance transport, high-temperature industrial heat, agriculture, and chemical production, hydrogen-based fuels and renewable natural gas remain attractive options, but the challenges related to their scaling opportunities and costs must be resolved,” says MIT Joint Program Deputy Director Sergey Paltsev, a lead author of the 2023 Global Change Outlook.

      Water, food, and land

      With a global population projected to reach 9.9 billion by 2050, the Current Trends scenario indicates that more than half of the world’s population will experience pressures to its water supply, and that three of every 10 people will live in water basins where compounding societal and environmental pressures on water resources will be experienced. Population projections under combined water stress in all scenarios reveal that the Accelerated Actions scenario can reduce approximately 40 million of the additional 570 million people living in water-stressed basins at mid-century.

      Under the Current Trends scenario, agriculture and food production will keep growing. This will increase pressure for land-use change, water use, and use of energy-intensive inputs, which will also lead to higher greenhouse gas emissions. Under the Accelerated Actions scenario, less agricultural and food output is observed by 2050 compared to the Current Trends scenario, since this scenario affects economic growth and increases production costs. Livestock production is more greenhouse gas emissions-intensive than crop and food production, which, under carbon-pricing policies, drives demand downward and increases costs and prices. Such impacts are transmitted to the food sector and imply lower consumption of livestock-based products.

      Land-use changes in the Accelerated Actions scenario are similar to those in the Current Trends scenario by 2050, except for land dedicated to bioenergy production. At the world level, the Accelerated Actions scenario requires cropland area to increase by 1 percent and pastureland to decrease by 4.2 percent, but land use for bioenergy must increase by 44 percent.

      Climate trends

      Under the Current Trends scenario, the world is likely (more than 50 percent probability) to exceed 2 C global climate warming by 2060, 2.8 C by 2100, and 3.8 C by 2150. Our latest climate-model information indicates that maximum temperatures will likely outpace mean temperature trends over much of North and South America, Europe, northern and southeast Asia, and southern parts of Africa and Australasia. So as human-forced climate warming intensifies, these regions are expected to experience more pronounced record-breaking extreme heat events.

      Under the Accelerated Actions scenario, global temperature will continue to rise through the next two decades. But by 2050, global temperature will stabilize, and then slightly decline through the latter half of the century.

      “By 2100, the Accelerated Actions scenario indicates that the world can be virtually assured of remaining below 2 C of global warming,” says MIT Joint Program Deputy Director C. Adam Schlosser, a lead author of the report. “Nevertheless, additional policy mechanisms must be designed with more comprehensive targets that also support a cleaner environment, sustainable resources, as well as improved and equitable human health.”

      The Accelerated Actions scenario not only stabilizes global precipitation increase (by 2060), but substantially reduces the magnitude and potential range of increases to almost one-third of Current Trends global precipitation changes. Any global increase in precipitation heightens flood risk worldwide, so policies aligned with the Accelerated Actions scenario would considerably reduce that risk.

      Prospects for meeting Paris Agreement climate goals

      Numerous countries and regions are progressing in fulfilling their Paris Agreement pledges. Many have declared more ambitious greenhouse gas emissions-mitigation goals, while financing to assist the least-developed countries in sustainable development is not forthcoming at the levels needed. In this year’s Global Stocktake Synthesis Report, the U.N. Framework Convention on Climate Change evaluated emissions reductions communicated by the parties of the Paris Agreement and concluded that global emissions are not on track to fulfill the most ambitious long-term global temperature goals of the Paris Agreement (to keep warming well below 2 C — and, ideally, 1.5 C — above pre-industrial levels), and there is a rapidly narrowing window to raise ambition and implement existing commitments in order to achieve those targets. The Current Trends scenario arrives at the same conclusion.

      The 2023 Global Change Outlook finds that both global temperature targets remain achievable, but require much deeper near-term emissions reductions than those embodied in current NDCs.

      Reducing climate risk

      This report explores two well-known sets of risks posed by climate change. Research highlighted indicates that elevated climate-related physical risks will continue to evolve by mid-century, along with heightened transition risks that arise from shifts in the political, technological, social, and economic landscapes that are likely to occur during the transition to a low-carbon economy.

      “Our Outlook shows that without aggressive actions the world will surpass critical greenhouse gas concentration thresholds and climate targets in the coming decades,” says MIT Joint Program Director Ronald Prinn. “While the costs of inaction are getting higher, the costs of action are more manageable.” More

    • 75 Shares159 Views

      in Environment

      Unlocking the secrets of natural materials

      by

      Growing up in Milan, Benedetto Marelli liked figuring out how things worked. He repaired broken devices simply to have the opportunity to take them apart and put them together again. Also, from a young age, he had a strong desire to make a positive impact on the world. Enrolling at the Polytechnic University of Milan, he chose to study engineering.

      “Engineering seemed like the right fit to fulfill my passions at the intersection of discovering how the world works, together with understanding the rules of nature and harnessing this knowledge to create something new that could positively impact our society,” says Marelli, MIT’s Paul M. Cook Career Development Associate Professor of Civil and Environmental Engineering.

      Marelli decided to focus on biomedical engineering, which at the time was the closest thing available to biological engineering. “I liked the idea of pursuing studies that provided me a background to engineer life,” in order to improve human health and agriculture, he says.

      Marelli went on to earn a PhD in materials science and engineering at McGill University and then worked in Tufts University’s biomaterials Silklab as a postdoc. After his postdoc, Marelli was drawn to MIT’s Department of Civil and Environmental in large part because of the work of Markus Buehler, MIT’s McAfee Professor of Engineering, who studies how to design new materials by understanding the architecture of natural ones.

      “This resonated with my training and idea of using nature’s building blocks to build a more sustainable society,” Marelli says. “It was a big leap forward for me to go from biomedical engineering to civil and environmental engineering. It meant completely changing my community, understanding what I could teach and how to mentor students in a new engineering branch. As Markus is working with silk to study how to engineer better materials, this made me see a clear connection with what I was doing and what I could be doing. I consider him one of my mentors here at MIT and was fortunate to end up collaborating with him.”

      Marelli’s research is aimed at mitigating several pressing global problems, he says.

      “Boosting food production to provide food security to an ever-increasing population, soil restoration, decreasing the environmental impact of fertilizers, and addressing stressors coming from climate change are societal challenges that need the development of rapidly scalable and deployable technologies,” he says.

      Marelli and his fellow researchers have developed coatings derived from natural silk that extend the shelf life of food, deliver biofertilizers to seeds planted in salty, unproductive soils, and allow seeds to establish healthier plants and increase crop yield in drought-stricken lands. The technologies have performed well in field tests being conducted in Morocco in collaboration with the Mohammed VI Polytechnic University in Ben Guerir, according to Marelli, and offer much potential.

      “I believe that with this technology, together with the common efforts shared by the MIT PIs participating in the Climate Grand Challenge on Revolutionizing Agriculture, we have a  real opportunity to positively impact planetary health and find new solutions that work in both rural settings and highly modernized agricultural fields,” says Marelli, who recently earned tenure.

      As a researcher and entrepreneur with about 20 patents to his name and awards including a National Science Foundation CAREER award, the Presidential Early Career Award for Scientists and Engineers award, and the Ole Madsen Mentoring Award, Marelli says that in general his insights into structural proteins — and how to use that understanding to manufacture advanced materials at multiple scales — are among his proudest achievements.

      More specifically, Marelli cites one of his breakthroughs involving a strawberry. Having dipped the berry in an odorless, tasteless edible silk suspension as part of a cooking contest held in his postdoctoral lab, he accidentally left it on his bench, only to find a week or so later that it had been well-preserved.

      “The coating of the strawberry to increase its shelf life is difficult to beat when it comes to inspiring people that natural polymers can serve as technical materials that can positively impact our society” by lessening food waste and the need for energy-intensive refrigerated shipping, Marelli says.

      When Marelli won the BioInnovation Institute and Science Prize for Innovation in 2022, he told the journal Science that he thinks students should be encouraged to choose an entrepreneurial path. He acknowledged the steepness of the learning curve of being an entrepreneur but also pointed out how the impact of research can be exponentially increased.

      He expanded on this idea more recently.

      “I believe an increasing number of academics and graduate students should try to get their hands ‘dirty’ with entrepreneurial efforts. We live in a time where academics are called to have a tangible impact on our society, and translating what we study in our labs is clearly a good way to employ our students and enhance the global effort to develop new technology that can make our society more sustainable and equitable,” Marelli says.

      Referring to a spinoff company, Mori, that grew out of the coated strawberry discovery and that develops silk-based products to preserve a wide range of perishable foods, Marelli says he finds it very satisfying to know that Mori has a product on the market that came out of his research efforts — and that 80 people are working to translate the discovery from “lab to fork.”

      “Knowing that the technology can move the needle in crises such as food waste and food-related environmental impact is the highest reward of all,” he says.

      Marelli says he tells students who are seeking solutions to extremely complicated problems to come up with one solution, “however crazy it might be,” and then do an extensive literature review to see what other researchers have done and whether “there is any hint that points toward developing their solution.”

      “Once we understand the feasibility, I typically work with them to simplify it as much as we can, and then to break down the problem in small parts that are addressable in series and/or in parallel,” Marelli says.

      That process of discovery is ongoing. Asked which of his technologies will have the greatest impact on the world, Marelli says, “I’d like to think it’s the ones that still need to be discovered.” More

    • 113 Shares179 Views

      in Security

      Microbes could help reduce the need for chemical fertilizers

      by

      Production of chemical fertilizers accounts for about 1.5 percent of the world’s greenhouse gas emissions. MIT chemists hope to help reduce that carbon footprint by replacing some chemical fertilizer with a more sustainable source — bacteria.

      Bacteria that can convert nitrogen gas to ammonia could not only provide nutrients that plants need, but also help regenerate soil and protect plants from pests. However, these bacteria are sensitive to heat and humidity, so it’s difficult to scale up their manufacture and ship them to farms.

      To overcome that obstacle, MIT chemical engineers have devised a metal-organic coating that protects bacterial cells from damage without impeding their growth or function. In a new study, they found that these coated bacteria improved the germination rate of a variety of seeds, including vegetables such as corn and bok choy.

      This coating could make it much easier for farmers to deploy microbes as fertilizers, says Ariel Furst, the Paul M. Cook Career Development Assistant Professor of Chemical Engineering at MIT and the senior author of the study.

      “We can protect them from the drying process, which would allow us to distribute them much more easily and with less cost because they’re a dried powder instead of in liquid,” she says. “They can also withstand heat up to 132 degrees Fahrenheit, which means that you wouldn’t have to use cold storage for these microbes.”

      Benjamin Burke ’23 and postdoc Gang Fan are the lead authors of the open-access paper, which appears in the Journal of the American Chemical Society Au. MIT undergraduate Pris Wasuwanich and Evan Moore ’23 are also authors of the study.

      Protecting microbes

      Chemical fertilizers are manufactured using an energy-intensive process known as Haber-Bosch, which uses extremely high pressures to combine nitrogen from the air with hydrogen to make ammonia.

      In addition to the significant carbon footprint of this process, another drawback to chemical fertilizers is that long-term use eventually depletes the nutrients in the soil. To help restore soil, some farmers have turned to “regenerative agriculture,” which uses a variety of strategies, including crop rotation and composting, to keep soil healthy. Nitrogen-fixing bacteria, which convert nitrogen gas to ammonia, can aid in this approach.

      Some farmers have already begun deploying these “microbial fertilizers,” growing them in large onsite fermenters before applying them to the soil. However, this is cost-prohibitive for many farmers.

      Shipping these bacteria to rural areas is not currently a viable option, because they are susceptible to heat damage. The microbes are also too delicate to survive the freeze-drying process that would make them easier to transport.

      To protect the microbes from both heat and freeze-drying, Furst decided to apply a coating called a metal-phenol network (MPN), which she has previously developed to encapsulate microbes for other uses, such as protecting therapeutic bacteria delivered to the digestive tract.

      The coatings contain two components — a metal and an organic compound called a polyphenol — that can self-assemble into a protective shell. The metals used for the coatings, including iron, manganese, aluminum, and zinc, are considered safe as food additives. Polyphenols, which are often found in plants, include molecules such as tannins and other antioxidants. The FDA classifies many of these polyphenols as GRAS (generally regarded as safe).

      “We are using these natural food-grade compounds that are known to have benefits on their own, and then they form these little suits of armor that protect the microbes,” Furst says.

      For this study, the researchers created 12 different MPNs and used them to encapsulate Pseudomonas chlororaphis, a nitrogen-fixing bacterium that also protects plants against harmful fungi and other pests. They found that all of the coatings protected the bacteria from temperatures up to 50 degrees Celsius (122 degrees Fahrenheit), and also from relative humidity up to 48 percent. The coatings also kept the microbes alive during the freeze-drying process.

      A boost for seeds

      Using microbes coated with the most effective MPN — a combination of manganese and a polyphenol called epigallocatechin gallate (EGCG) — the researchers tested their ability to help seeds germinate in a lab dish. They heated the coated microbes to 50 C before placing them in the dish, and compared them to fresh uncoated microbes and freeze-dried uncoated microbes.

      The researchers found that the coated microbes improved the seeds’ germination rate by 150 percent, compared to seeds treated with fresh, uncoated microbes. This result was consistent across several different types of seeds, including dill, corn, radishes, and bok choy.

      Furst has started a company called Seia Bio to commercialize the coated bacteria for large-scale use in regenerative agriculture. She hopes that the low cost of the manufacturing process will help make microbial fertilizers accessible to small-scale farmers who don’t have the fermenters needed to grow such microbes.

      “When we think about developing technology, we need to intentionally design it to be inexpensive and accessible, and that’s what this technology is. It would help democratize regenerative agriculture,” she says.

      The research was funded by the Army Research Office, a National Institutes of Health New Innovator Award, a National Institute for Environmental Health Sciences Core Center Grant, the CIFAR Azrieli Global Scholars Program, the MIT J-WAFS Program, the MIT Climate and Sustainability Consortium, and the MIT Deshpande Center. More

    • 100 Shares99 Views

      in Environment

      Smart irrigation technology covers “more crop per drop”

      by

      In agriculture today, robots and drones can monitor fields, temperature and moisture sensors can be automated to meet crop needs, and a host of other systems and devices make farms more efficient, resource-conscious, and profitable. The use of precision agriculture, as these technologies are collectively known, offers significant advantages. However, because the technology can be costly, it remains out of reach for the majority of the world’s farmers.

      “Many of the poor around the world are small, subsistence farmers,” says Susan Amrose, research scientist with the Global Engineering and Research (GEAR) Lab at MIT. “With intensification of food production needs, worsening soil, water scarcity, and smaller plots, these farmers can’t continue with their current practices.”

      By some estimates, the global demand for fresh water will outstrip supply by as much as 40 percent by the end of the decade. Nearly 80 percent of the world’s 570 million farms are classed as smallholder farms, with many located in under-resourced and water-stressed regions. With rapid population growth and climate change driving up demand for food, and with more strain on natural resources, increasing the adoption of sustainable agricultural practices among smallholder farmers is vital. 

      Amrose, who helps lead desalination, drip irrigation, water, and sanitation projects for GEAR Lab, says these small farmers need to move to more mechanized practices. “We’re trying to make it much, much more affordable for farmers to utilize solar-powered irrigation, and to have access to tools that, right now, they’re priced out of,” she says. “More crop per drop, more crop per area, that’s our goal.”

      Play video

      No Drop to Spare: MIT creates affordable, user-driven smart irrigation technology | MIT Mechanical Engineering

      Drip irrigation systems release water and nutrients in controlled volumes directly to the root zone of the crop through a network of pipes and emitters. These systems can reduce water consumption by 20 to 60 percent when compared to conventional flood irrigation methods.

      “Agriculture uses 70 percent of the fresh water that’s in use across the globe. Large-scale adoption and correct management of drip irrigation could help to reduce consumption of fresh water, which is especially critical for regions experiencing water shortages or groundwater depletion,” says Carolyn Sheline SM ’19, a PhD student and member of the GEAR Lab’s Drip Irrigation team. “A lot of irrigation technology is developed for larger farms that can put more money into it — but inexpensive doesn’t need to mean ‘not technologically advanced.’”

      GEAR Lab has created several drip irrigation technology solutions to date, including a low-pressure drip emitter that has been shown to reduce pumping energy by more than 50 percent when compared to existing emitters; a systems-level optimization model that analyzes factors like local weather conditions and crop layouts, to cut overall system operation costs by up to 30 percent; and a low-cost precision irrigation controller that optimizes system energy and water use, enabling farmers to operate the system on an ideal schedule given their specific resources, needs, and preferences. The controller has recently been shown to reduce water consumption by over 40 percent when compared to traditional practices.

      To build these new, affordable technologies, the team tapped into a critical knowledge source — the farmers themselves.

      “We didn’t just create technology in isolation — we also advanced our understanding of how people would interact with and value this technology, and we did that before the technology had come to fruition,” says Amos Winter SM ’05, PhD ’11, associate professor of mechanical engineering and MIT GEAR Lab principal investigator. “Getting affirmations that farmers would value what the technology would do before we finished it was incredibly important.”

      The team held “Farmer Field Days” and conducted interviews with more than 200 farmers, suppliers, and industry professionals in Kenya, Morocco, and Jordan, the regions selected to host field pilot test sites. These specific sites were selected for a variety of reasons, including solar availability and water scarcity, and because all were great candidate markets for eventual adoption of the technology.

      “People usually understand their own problems really well, and they’re very good at coming up with solutions to them,” says Fiona Grant ’17, SM ’19, also a PhD candidate with the GEAR Lab Drip Irrigation team. “As designers, our role really is to provide a different set of expertise and another avenue for them to get the tools or the resources that they need.”

      The controller, for example, takes in weather information, like relative humidity, temperature, wind speed values, and precipitation. Then, using artificial intelligence, it calculates and predicts the area’s solar exposure for the day and the exact irrigation needs for the farmer, and sends information to their smartphone. How much, or how little, automation an individual site uses remains up to the farmer. In its first season of operation on a Moroccan test site, GEAR Lab technology reduced water consumption by 44 percent and energy by 38 percent when compared to a neighboring farm using traditional drip irrigation practice.

      “The way you’re going to operate a system is going to have a big impact on the way you design it,” says Grant. “We gained a sense of what farmers would be willing to change, or not, regarding interactions with the system. We found that what we might change, and what would be acceptable to change, were not necessarily the same thing.”

      GEAR Lab alumna Georgia Van de Zande ’15, SM ’18, PhD ’23, concurs. “It’s about more than just delivering a lower-cost system, it’s also about creating something they’re going to want to use and want to trust.”

      In Jordan, researchers at a full-scale test farm are operating a solar-powered drip system with a prototype of the controller and are receiving smartphone commands on when to open and close the manual valves. In Morocco, the controller is operating at a research farm with a fully automated hydraulic system; researchers are monitoring the irrigation and conducting additional agronomic tasks. In Kenya, where precision agriculture and smart irrigation haven’t yet seen very much adoption, a simpler version of the controller serves to provide educational and training information in addition to offering scheduling and control capabilities.

      Knowledge is power for the farmers, and for designers and engineers, too. If an engineer can know a user’s requirements, Winter says, they’re much more likely to create a successful solution.

      “The most powerful tool a designer can have is perspective. I have one perspective — the math and science and tech innovation side — but I don’t know a thing about what it’s like to live every day as a farmer in Jordan or Morocco,” says Winter. “I don’t know what clogs the filters, or who shuts off the water. If you can see the world through the eyes of stakeholders, you’re going to spot requirements and constraints that you wouldn’t have picked up on otherwise.”

      Winter says the technology his team is building is exciting for a lot of reasons.

      “To be in a situation where the world is saying, ‘we need to deal with water stress, we need to deal with climate adaptation, and we need to particularly do this in resource-constrained countries,’ and to be in a position where we can do something about it and produce something of tremendous value and efficacy is incredible,” says Winter. “Solving the right problem at the right time, on a massive scale, is thrilling.” More

    • 88 Shares139 Views

      in Environment

      Ancient Amazonians intentionally created fertile “dark earth”

      by

      The Amazon river basin is known for its immense and lush tropical forests, so one might assume that the Amazon’s land is equally rich. In fact, the soils underlying the forested vegetation, particularly in the hilly uplands, are surprisingly infertile. Much of the Amazon’s soil is acidic and low in nutrients, making it notoriously difficult to farm.

      But over the years, archaeologists have dug up mysteriously black and fertile patches of ancient soils in hundreds of sites across the Amazon. This “dark earth” has been found in and around human settlements dating back hundreds to thousands of years. And it has been a matter of some debate as to whether the super-rich soil was purposefully created or a coincidental byproduct of these ancient cultures.

      Now, a study led by researchers at MIT, the University of Florida, and in Brazil aims to settle the debate over dark earth’s origins. The team has pieced together results from soil analyses, ethnographic observations, and interviews with modern Indigenous communities, to show that dark earth was intentionally produced by ancient Amazonians as a way to improve the soil and sustain large and complex societies.

      “If you want to have large settlements, you need a nutritional base. But the soil in the Amazon is extensively leached of nutrients, and naturally poor for growing most crops,” says Taylor Perron, the Cecil and Ida Green Professor of Earth, Atmospheric and Planetary Sciences at MIT. “We argue here that people played a role in creating dark earth, and intentionally modified the ancient environment to make it a better place for human populations.”

      And as it turns out, dark earth contains huge amounts of stored carbon. As generations worked the soil, for instance by enriching it with scraps of food, charcoal, and waste, the earth accumulated the carbon-rich detritus and kept it locked up for hundreds to thousands of years. By purposely producing dark earth, then, early Amazonians may have also unintentionally created a powerful, carbon-sequestering soil.

      “The ancient Amazonians put a lot of carbon in the soil, and a lot of that is still there today,” says co-author Samuel Goldberg, who performed the data analysis as a graduate student at MIT and is now an assistant professor at the University of Miami. “That’s exactly what we want for climate change mitigation efforts. Maybe we could adapt some of their indigenous strategies on a larger scale, to lock up carbon in soil, in ways that we now know would stay there for a long time.”

      The team’s study appears today in Science Advances. Other authors include former MIT postdoc and lead author Morgan Schmidt, anthropologist Michael Heckenberger of the University of Florida, and collaborators from multiple institutions across Brazil.

      Modern intent

      In their current study, the team synthesized observations and data that Schmidt, Heckenberger, and others had previously gathered, while working with Indigenous communities in the Amazon since the early 2000s,  with new data collected in 2018-19. The scientists focused their fieldwork in the Kuikuro Indigenous Territory in the Upper Xingu River basin in the southeastern Amazon. This region is home to modern Kuikuro villages as well as archaeological sites where the ancestors of the Kuikuro are thought to have lived. Over multiple visits to the region, Schmidt, then a graduate student at the University of Florida, was struck by the darker soil around some archaeological sites.

      “When I saw this dark earth and how fertile it was, and started digging into what was known about it, I found it was a mysterious thing — no one really knew where it came from,” he says.

      Schmidt and his colleagues began making observations of the modern Kuikuro’s practices of managing the soil. These practices include generating “middens” — piles of waste and food scraps, similar to compost heaps, that are maintained in certain locations around the center of a village. After some time, these waste piles decompose and mix with the soil to form a dark and fertile earth, that residents then use to plant crops. The researchers also observed that Kuikuro farmers spread organic waste and ash on farther fields, which also generates dark earth, where they can then grow more crops.

      “We saw activities they did to modify the soil and increase the elements, like spreading ash on the ground, or spreading charcoal around the base of the tree, which were obviously intentional actions,” Schmidt says.

      In addition to these observations, they also conducted interviews with villagers to document the Kuikuro’s beliefs and practices relating to dark earth. In some of these interviews, villagers referred to dark earth as “eegepe,” and described their daily practices in creating and cultivating the rich soil to improve its agricultural potential.

      Based on these observations and interviews with the Kuikuro, it was clear that Indigenous communities today intentionally produce dark earth, through their practices to improve the soil. But could the dark earth found in nearby archaeological sites have been made through similar intentional practices?

      A bridge in soil

      In search of a connection, Schmidt joined Perron’s group as a postdoc at MIT. Together, he, Perron, and Goldberg carried out a meticulous analysis of soils in both archaeological and modern sites in the Upper Xingu region. They discovered similarities in dark earth’s spatial structure: Deposits of dark earth were found in a radial pattern, concentrating mostly in the center of both modern and ancient settlements, and stretching, like spokes of a wheel, out to the edges. Modern and ancient dark earth was also similar in composition, and was enriched in the same elements, such as carbon, phosphorus, and other nutrients.

      “These are all the elements that are in humans, animals, and plants, and they’re the ones that reduce the aluminum toxicity in soil, which is a notorious problem in the Amazon,” Schmidt says. “All these elements make the soil better for plant growth.”

      “The key bridge between the modern and ancient times is the soil,” Goldberg adds. “Because we see this correspondence between the two time periods, we can infer that these practices that we can observe and ask people about today, were also happening in the past.”

      In other words, the team was able to show for the first time that ancient Amazonians intentionally worked the soil, likely through practices similar to today’s, in order to grow enough crops to sustain large communities.

      Going a step further, the team calculated the amount of carbon in ancient dark earth. They combined their measurements of soil samples, with maps of where dark earth has been found through several ancient settlements. Their estimates revealed that each ancient village contains several thousand tons of carbon that has been sequestered in the soil for hundreds of years as a result of Indigenous, human activities.

      As the team concludes in their paper, “modern sustainable agriculture and climate change mitigation efforts, inspired by the persistent fertility of ancient dark earth, can draw on traditional methods practiced to this day by Indigenous Amazonians.”

      This research at MIT was supported, in part, by the Abdul Latif Jameel Water and Food Systems Lab and the Department of the Air Force Artificial Intelligence Accelerator. Field research was supported by grants to the University of Florida from the National Science Foundation, the Wenner-Gren Foundation and the William Talbott Hillman Foundation, and was sponsored in Brazil by the Museu Goeldi and Museu Nacional. More

    • 88 Shares169 Views

      in Environment

      How to tackle the global deforestation crisis

      by

      Imagine if France, Germany, and Spain were completely blanketed in forests — and then all those trees were quickly chopped down. That’s nearly the amount of deforestation that occurred globally between 2001 and 2020, with profound consequences.

      Deforestation is a major contributor to climate change, producing between 6 and 17 percent of global greenhouse gas emissions, according to a 2009 study. Meanwhile, because trees also absorb carbon dioxide, removing it from the atmosphere, they help keep the Earth cooler. And climate change aside, forests protect biodiversity.

      “Climate change and biodiversity make this a global problem, not a local problem,” says MIT economist Ben Olken. “Deciding to cut down trees or not has huge implications for the world.”

      But deforestation is often financially profitable, so it continues at a rapid rate. Researchers can now measure this trend closely: In the last quarter-century, satellite-based technology has led to a paradigm change in charting deforestation. New deforestation datasets, based on the Landsat satellites, for instance, track forest change since 2000 with resolution at 30 meters, while many other products now offer frequent imaging at close resolution.

      “Part of this revolution in measurement is accuracy, and the other part is coverage,” says Clare Balboni, an assistant professor of economics at the London School of Economics (LSE). “On-site observation is very expensive and logistically challenging, and you’re talking about case studies. These satellite-based data sets just open up opportunities to see deforestation at scale, systematically, across the globe.”

      Balboni and Olken have now helped write a new paper providing a road map for thinking about this crisis. The open-access article, “The Economics of Tropical Deforestation,” appears this month in the Annual Review of Economics. The co-authors are Balboni, a former MIT faculty member; Aaron Berman, a PhD candidate in MIT’s Department of Economics; Robin Burgess, an LSE professor; and Olken, MIT’s Jane Berkowitz Carlton and Dennis William Carlton Professor of Microeconomics. Balboni and Olken have also conducted primary research in this area, along with Burgess.

      So, how can the world tackle deforestation? It starts with understanding the problem.

      Replacing forests with farms

      Several decades ago, some thinkers, including the famous MIT economist Paul Samuelson in the 1970s, built models to study forests as a renewable resource; Samuelson calculated the “maximum sustained yield” at which a forest could be cleared while being regrown. These frameworks were designed to think about tree farms or the U.S. national forest system, where a fraction of trees would be cut each year, and then new trees would be grown over time to take their place.

      But deforestation today, particularly in tropical areas, often looks very different, and forest regeneration is not common.

      Indeed, as Balboni and Olken emphasize, deforestation is now rampant partly because the profits from chopping down trees come not just from timber, but from replacing forests with agriculture. In Brazil, deforestation has increased along with agricultural prices; in Indonesia, clearing trees accelerated as the global price of palm oil went up, leading companies to replace forests with palm tree orchards.

      All this tree-clearing creates a familiar situation: The globally shared costs of climate change from deforestation are “externalities,” as economists say, imposed on everyone else by the people removing forest land. It is akin to a company that pollutes into a river, affecting the water quality of residents.

      “Economics has changed the way it thinks about this over the last 50 years, and two things are central,” Olken says. “The relevance of global externalities is very important, and the conceptualization of alternate land uses is very important.” This also means traditional forest-management guidance about regrowth is not enough. With the economic dynamics in mind, which policies might work, and why?

      The search for solutions

      As Balboni and Olken note, economists often recommend “Pigouvian” taxes (named after the British economist Arthur Pigou) in these cases, levied against people imposing externalities on others. And yet, it can be hard to identify who is doing the deforesting.

      Instead of taxing people for clearing forests, governments can pay people to keep forests intact. The UN uses Payments for Environmental Services (PES) as part of its REDD+ (Reducing Emissions from Deforestation and forest Degradation) program. However, it is similarly tough to identify the optimal landowners to subsidize, and these payments may not match the quick cash-in of deforestation. A 2017 study in Uganda showed PES reduced deforestation somewhat; a 2022 study in Indonesia found no reduction; another 2022 study, in Brazil, showed again that some forest protection resulted.

      “There’s mixed evidence from many of these [studies],” Balboni says. These policies, she notes, must reach people who would otherwise clear forests, and a key question is, “How can we assess their success compared to what would have happened anyway?”

      Some places have tried cash transfer programs for larger populations. In Indonesia, a 2020 study found such subsidies reduced deforestation near villages by 30 percent. But in Mexico, a similar program meant more people could afford milk and meat, again creating demand for more agriculture and thus leading to more forest-clearing.

      At this point, it might seem that laws simply banning deforestation in key areas would work best — indeed, about 16 percent of the world’s land overall is protected in some way. Yet the dynamics of protection are tricky. Even with protected areas in place, there is still “leakage” of deforestation into other regions. 

      Still more approaches exist, including “nonstate agreements,” such as the Amazon Soy Moratorium in Brazil, in which grain traders pledged not to buy soy from deforested lands, and reduced deforestation without “leakage.”

      Also, intriguingly, a 2008 policy change in the Brazilian Amazon made agricultural credit harder to obtain by requiring recipients to comply with environmental and land registration rules. The result? Deforestation dropped by up to 60 percent over nearly a decade. 

      Politics and pulp

      Overall, Balboni and Olken observe, beyond “externalities,” two major challenges exist. One, it is often unclear who holds property rights in forests. In these circumstances, deforestation seems to increase. Two, deforestation is subject to political battles.

      For instance, as economist Bard Harstad of Stanford University has observed, environmental lobbying is asymmetric. Balboni and Olken write: “The conservationist lobby must pay the government in perpetuity … while the deforestation-oriented lobby need pay only once to deforest in the present.” And political instability leads to more deforestation because “the current administration places lower value on future conservation payments.”

      Even so, national political measures can work. In the Amazon from 2001 to 2005, Brazilian deforestation rates were three to four times higher than on similar land across the border, but that imbalance vanished once the country passed conservation measures in 2006. However, deforestation ramped up again after a 2014 change in government. Looking at particular monitoring approaches, a study of Brazil’s satellite-based Real-Time System for Detection of Deforestation (DETER), launched in 2004, suggests that a 50 percent annual increase in its use in municipalities created a 25 percent reduction in deforestation from 2006 to 2016.

      How precisely politics matters may depend on the context. In a 2021 paper, Balboni and Olken (with three colleagues) found that deforestation actually decreased around elections in Indonesia. Conversely, in Brazil, one study found that deforestation rates were 8 to 10 percent higher where mayors were running for re-election between 2002 and 2012, suggesting incumbents had deforestation industry support.

      “The research there is aiming to understand what the political economy drivers are,” Olken says, “with the idea that if you understand those things, reform in those countries is more likely.”

      Looking ahead, Balboni and Olken also suggest that new research estimating the value of intact forest land intact could influence public debates. And while many scholars have studied deforestation in Brazil and Indonesia, fewer have examined the Democratic Republic of Congo, another deforestation leader, and sub-Saharan Africa.

      Deforestation is an ongoing crisis. But thanks to satellites and many recent studies, experts know vastly more about the problem than they did a decade or two ago, and with an economics toolkit, can evaluate the incentives and dynamics at play.

      “To the extent that there’s ambuiguity across different contexts with different findings, part of the point of our review piece is to draw out common themes — the important considerations in determining which policy levers can [work] in different circumstances,” Balboni says. “That’s a fast-evolving area. We don’t have all the answers, but part of the process is bringing together growing evidence about [everything] that affects how successful those choices can be.” More

    • 125 Shares199 Views

      in Environment

      How forests can cut carbon, restore ecosystems, and create jobs

      by

      To limit the frequency and severity of droughts, wildfires, flooding, and other adverse consequences of climate change, nearly 200 countries committed to the Paris Agreement’s long-term goal of keeping global warming well below 2 degrees Celsius. According to the latest United Nations Intergovernmental Panel on Climate Change (IPCC) Report, achieving that goal will require both large-scale greenhouse gas (GHG) emissions reduction and removal of GHGs from the atmosphere.

      At present, the most efficient and scalable GHG-removal strategy is the massive planting of trees through reforestation or afforestation — a “natural climate solution” (NCS) that extracts atmospheric carbon dioxide through photosynthesis and soil carbon sequestration.

      Despite the potential of forestry-based NCS projects to address climate change, biodiversity loss, unemployment, and other societal needs — and their appeal to policymakers, funders, and citizens — they have yet to achieve critical mass, and often underperform due to a mix of interacting ecological, social, and financial constraints. To better understand these challenges and identify opportunities to overcome them, a team of researchers at Imperial College London and the MIT Joint Program on the Science and Policy of Global Change recently studied how environmental scientists, local stakeholders, and project funders perceive the risks and benefits of NCS projects, and how these perceptions impact project goals and performance. To that end, they surveyed and consulted with dozens of recognized experts and organizations spanning the fields of ecology, finance, climate policy, and social science.

      The team’s analysis, which appears in the journal Frontiers in Climate, found two main factors that have hindered the success of forestry-based NCS projects.

      First, the ambition — levels of carbon removal, ecosystem restoration, job creation, and other environmental and social targets — of selected NCS projects is limited by funders’ perceptions of their overall risk. Among other things, funders aim to minimize operational risk (e.g., Will newly planted trees survive and grow?), political risk (e.g., Just how secure is their access to the land where trees will be planted?); and reputational risk (e.g., Will the project be perceived as an exercise in “greenwashing,” or fall way short of its promised environmental and social benefits?). Funders seeking a financial return on their initial investment are also concerned about the dependability of complex monitoring, reporting, and verification methods used to quantify atmospheric carbon removal, biodiversity gains, and other metrics of project performance.

      Second, the environmental and social benefits of NCS projects are unlikely to be realized unless the local communities impacted by these projects are granted ownership over their implementation and outcomes. But while engaging with local communities is critical to project performance, it can be challenging both legally and financially to set up incentives (e.g., payment and other forms of compensation) to mobilize such engagement.

      “Many carbon offset projects raise legitimate concerns about their effectiveness,” says study lead author Bonnie Waring, a senior lecturer at the Grantham Institute on Climate Change and the Environment, Imperial College London. “However, if nature climate solution projects are done properly, they can help with sustainable development and empower local communities.”

      Drawing on surveys and consultations with NCS experts, stakeholders, and funders, the research team highlighted several recommendations on how to overcome key challenges faced by forestry-based NCS projects and boost their environmental and social performance.

      These recommendations include encouraging funders to evaluate projects based on robust internal governance, support from regional and national governments, secure land tenure, material benefits for local communities, and full participation of community members from across a spectrum of socioeconomic groups; improving the credibility and verifiability of project emissions reductions and related co-benefits; and maintaining an open dialogue and shared costs and benefits among those who fund, implement, and benefit from these projects.

      “Addressing climate change requires approaches that include emissions mitigation from economic activities paired with greenhouse gas reductions by natural ecosystems,” says Sergey Paltsev, a co-author of the study and deputy director of the MIT Joint Program. “Guided by these recommendations, we advocate for a proper scaling-up of NCS activities from project levels to help assure integrity of emissions reductions across entire countries.” More