By Jean Thilmany* How a Seafood Nursery Feeds Millions The word is out about the ways seagrass aids the environment, but more needs to be known about how this vital ecosystem boosts local economies. For those who are not familiar with seagrass, the term covers the many species of the world’s only flowering underwater plant. Seagrass spreads along the ocean floor through rhizomes, often hugging shorelines in colonies that resemble the rolling, grassy meadows found on land. Seagrasses are found globally in temperate and tropical waters where their biodiverse ecosystems rival those of coral reefs, protecting and nourishing wide varieties of marine prey and predator alike. Seagrass Studies Ignore Local Economic Benefits Environmentalists have spearheaded the call to protect and restore the seagrasses. Not only are fields of seagrass superior at carbon sequestration, they can slow, and even help rectify, ocean acidification, according to a 2021 study by the Monterey Aquarium Research Institute in California. Researchers at Swansea University in Wales describe seagrass as a "nature-based solution for greenhouse gas mitigation," calling it "vital for biodiversity." But unfortunately, the immense ecological importance of seagrass beds doesn’t translate into wholesale preservation efforts. Seagrass keeps communities from falling into poverty, or into greater poverty. Often overlooked are seagrass beds’ significant economic importance to coastal communities. In fact, seagrass keeps communities from falling into poverty, or into greater poverty, says Benjamin L.H. Jones, a professor in the department of Ecology, Environment, and Plant Sciences at Stockholm University in Sweden. Jones is the lead author of a study that looked at the role seagrass plays in local economic income. The study, published in the June 2022 issue of the journal Ocean & Coastal Management, is one of the first of its kind to define the importance of seagrass to the coastal populations, Jones says. "The support that seagrass meadows provide to communities can no longer be ignored; doing so would create further poverty for the most vulnerable in society," Jones says. Food Security: On Par with Environmental Concerns Efforts to restore and maintain fields of seagrass in oceans and seas mainly center around environmental arguments, Jones said. But how will the local populations that depend on seagrass for the fish and seafood they eat and for their livelihoods be affected by vanishing seagrass meadows? Their plights should also be a consideration in preservation efforts, Jones says. When seagrass meadows are lost, household income goes down, Jones and his fellow researchers found. In Southeast Asia and other tropical regions, plentiful fields of seagrass help alleviate poverty in local communities. That’s because many residents comb through the meadows to catch the fish, crab, turtles, and shrimp that live among the grass-like plants. Seagrass is a prominent food source for these households, the study finds. Small-scale fisheries also rely on plentiful fields of seagrass because many types of fish—both large and small—live in the meadows, which proliferate relatively close to shore. In fact, Jones and his colleagues discovered that, wealthy or poor, all the households they studied relied on seagrass to one degree or another. By looking at income and other factors from 147 villages across four countries within the Indo-Pacific, the researchers were able to examine the ways the households depend on seagrass. Even wealthy households that fish offshore with their own boats also fish within beds of seagrass, Jones says. Actually, seagrass meadows serve as a nursery habitat "to over 1/5th of the world's largest 25 fisheries," according to a 2018 study. That includes pollock (see video), "the most landed species on the planet," wrote the study authors. But overfishing and pollution are rapidly diminishing seagrass meadows that these populations rely on. In fact, a football field of seagrass disappears every half hour, according to a study done last year by researchers at the University of California Davis and other institutions. Jones and his colleagues join environmentalists, politicians and others in calling for the conservation of seagrass meadows. "Safeguarding seagrass meadows across the Indo-Pacific is vital to alleviate poverty," he says. Push-Pull Needs of Fisheries and Seagrass Meadows The depletion of seagrass can threaten food security in a number of ways other than impoverishment, says Mariana Herrera, a marine science researcher at the University of Vigo in Spain. Particularly important is seagrass meadows’ role in supporting fisheries worldwide and bringing food to nearby populations, Herrera says. People in tropical countries often rely on small-scale fisheries for their everyday food needs, she says. Small-scale fishers often operate without boats or with small boards. They’re not able to fish far from the shore, meaning seagrass meadows are important to support the shore life that creates their livelihood, Herrera says. Many marine species that live close to the shore "are easy to target using low-tech fishing gear or simply collection by hand [allowing] such fisheries to prevail across the tropics, more so in low-income and emerging economies," writes Jones and colleagues in their paper. Small-scale fisheries are increasingly difficult to manage as they are tied to the fate of coastal habitats like seagrass meadows, which themselves are impacted by factors like poor water quality and coastal development, Herrera says. Meanwhile, Jones and his colleagues found that, in the 147 households they studied, low-income households that depend on seagrass for income from fishing could be hit hardest by such factors as habitat loss and overfishing. "If seagrass meadows are lost, the most vulnerable in society will have the most to lose," Jones says. "The support that seagrass meadows provide to communities can no longer be ignored, doing so would create further poverty for households that depend on seagrass for food and work." *Jean Thilmany is a freelance writer living in St. Paul, MN, who writes frequently about science and engineering topics.

By Jaqueline Sordi* The Brazilian waste picker Alex Cardoso was born and reborn many times among recyclable materials. Son and grandson of waste pickers, he had his first life-changing experience around paper boxes and plastic bottles when he was only two months old. His parents worked as self-employed waste pickers and collected materials every day to feed their family, carrying their newborns to work — that is, to the streets. On this particular day, one of the paper boxes collected hours earlier fell off the cart while they were heading home. The father, Alceu Cardoso, was inclined to leave the box on the street, but the mother, Tânia Maria, decided to pick it up. That was a lucky call: Alex was quietly sleeping inside that box. They had put their son there hours earlier to keep him warm during work. This “almost tragic” story happened 41 years ago. Four decades later, in 2020, Alex experienced the same fear for his life among recycled materials. With the beginning of the COVID-19 pandemic, he felt constantly in danger of being infected while working. But there was no choice other than to keep working. As most waste pickers in Brazil rely on income from the daily collection of materials, with no other sources of funds, they must either put themselves at risk or starve to death. “Even before the COVID-19 pandemic, we already worked in a pandemic-like situation. Most waste pickers in Brazil have to go to the streets every day without protection, exposed to all kinds of risks. Since last year, with the novel coronavirus, the vulnerability of the activity became more obvious,” he says. Like thousands of others working in the solid waste sector, Alex faces the challenges of being a waste picker every day, an activity that, despite being essential, lacks both recognition from society and protection by the government. In fact, to most people in Latin America, waste pickers are still invisible, and that is why they are one of the groups that have been hit the hardest since the beginning of the coronavirus pandemic, with thousands becoming ill and almost no access to information or support from local authorities. “There are particular challenges for the solid waste sector in general, whether formal or informal, because of the vulnerability of the activity due to unsanitary work environments, and the pandemic added an extra layer of vulnerability to this already precarious work,” explains Sonia Dias, a researcher at Women in Informal Employment: Globalizing and Organizing (WIEGO). The hazardous reality The National Recyclable Waste Pickers Movement (MNCR) estimates that there are around 800,000 waste pickers in Brazil. For years, the movement has been trying to have the activity recognized by the government. Some improvements have been made: In 2002, for example, the Brazilian National Classification of Occupations (CBO) recognized waste collecting as an occupation and entered it as such in the correspondent national registry. But the fact is that waste pickers are still informal workers, unprotected by legislation. Today, only 10 to 20 percent of them are organized through cooperatives or associations (groups, related or not to local governments, that regulate or protect an activity). For most of them, the hazardous reality is to go out every day without safety gear, which is particularly critical in the current health crisis, given the risks of infected materials getting mixed in with the general waste stream. Studies have shown that the novel coronavirus is transmitted mainly via tiny droplets that people exhale as they breathe, talk and cough. But these virus particles can remain infectious after a day spent on cardboard, at least two days on steel, and three on plastic. With little information about the risks, waste pickers remained (and some still are) in contact with all these materials for months with no protection. Worldwide, the reality is not that different. The International Labor Organization estimates that only 4 million of the 19 million to 24 million people in the waste management and recycling sector worldwide are formally employed. This might seem controversial, since they perform an essential service for the sustainability and health of our cities. According to the Institute of Applied Economic Research, waste pickers in Brazil—classified as those who “collect, select, and sell recyclable materials such as paper, cardboard, glass, as well as ferrous and non-ferrous materials and other reusable materials” (definition by the Ministry of Labor and Employment/CBO) — are responsible for around 90 percent of all recycling in the country, playing a vital role in the circular and green economies. “Over the years, I have learned that waste pickers help to solve one of the worst problems in the capitalist world. Even so, we must help and support each other all the time, because society still does not understand that this is a decent profession,” explains Alex Cardoso, who at 41 years of age is also a member of the MNCR and a university student in Porto Alegre in Brazil’s South Region. Impacts of the pandemic According to a study conducted by WIEGO, the early months of the pandemic were the hardest for waste pickers in Brazil. With municipal and state decrees calling on people to stay home, the collection and manual sorting of recyclable waste were suspended in several municipalities. Also, as a number of manufacturing plants went out of business, the buyers of recyclable materials either stopped buying or started to pay prices well below the standard. The prices have dropped by 50 percent on average, making the collection of various materials less attractive. In April, in order to generate income, some pickers resorted to the emergency aid offered by the federal government, but President Jair Bolsonaro indicated the intention to veto the inclusion of these workers as beneficiaries, and the majority of them lacked information about how or if it was possible to access those benefits. Aside from the economic issue, there was the health issue. “Surveys conducted in several Brazilian capitals throughout 2020 by the Brazilian Association of Sanitary and Environmental Engineering (ABES) showed that people who work with waste and recyclable materials had higher rates of death and contamination when compared to other activities,” explains Emília Wanda Rutkowski, an associate professor at the State University of Campinas (UniCamp) and a member of ABES. “I lost a lot of colleagues in the beginning of the pandemic, and the worst part is that they died, and we don’t even know where they are buried. It’s like they just disappeared,” says Carlos Antonio dos Reis, 53 years old. Born in São Paulo, the biggest city in the country, he has been working as a self-employed waste picker since he was nine years old, and because of the vulnerability of his work he has been living in extreme conditions for over a year. What kept Carlos and so many other waste pickers alive and hopeful—even though Brazil was one of the countries most affected by the pandemic, with over 400 thousand deaths—were the solidarity movements that provided support for these workers. “I was involved in organized movements that helped us to educate each other about the risks of our activity during the pandemic and showed us ways to protect ourselves. After the first dramatic months with no work, we started do go back to the streets with masks and other Personal Protective Equipment (PPE) that were either homemade or donated by these voluntary groups. There are still a lot of risks, but at least we felt a little safer while doing our jobs,” he says. A new chapter for waste pickers In fact, the WIEGO study showed how cooperatives and organized movements can play an important role in the lives of waste pickers, especially in critical times. Researchers found that after serious disruption in the first months of the pandemic, most cooperatives and associations were back in operation by May 2020. Almost all of them were using PPE, almost 80 percent had sent vulnerable members into isolation with their income guaranteed, and 45 percent were quarantining scrap before sorting it. Also, the prices paid for those materials slowly began to normalize. “Cooperatives have helped waste pickers address a wide range of important, day-to-day issues, including negotiating with public authorities and private intermediaries, occupational safety and health, gender-based violence, housing problems, legal protection, social protection, and access to storage space and local marketplaces,” Sonia Dias explains. But these improvements are still not enough to protect the solid waste sector. In 2021, a new survey conducted by the Project Cata Saúde Viraliza outlined the situation of waste pickers across the country a year after the beginning of the pandemic. The survey showed that many are still working without proper protective equipment and a number of them report shortages of recyclable materials available on the streets for collection. “As some activities from the solid waste sector were suspended at the beginning of the pandemic, people were discouraged from separating regular trash from recyclable material. But months passed and the activity was re-established, and still there was no government action to re-educate people about the importance of separating garbage for the recycling process. The result is that waste pickers today have less recyclable material available for collection. Many end up having to collect regular trash and separate it themselves. The result is that they can sell only a small percentage of what they collect on the streets,” says Dr. Rutkowski. For many researchers, one positive aspect of this crisis is that it has shed light on the importance and vulnerability of waste pickers worldwide. There is a consensus that governments around the globe will not integrate informal workers into their waste management systems overnight, but the workers’ historical fight for recognition might be entering a new chapter after the COVID-19 pandemic is over. Since their work has proved to be an essential part of the waste management system in every city of the globe, these workers should not stop their activity, but rather must be given proper conditions to continue working in a secure environment. And in order to contribute to that—now and after the pandemic is over—everyone can do their part by learning how to discard waste properly. It is recommended that recyclable materials be cleaned with soap and water or bleach prior to disposal. Material that is not washed should be left isolated for a period of five days prior to disposal. Sanitary protocols also recommend that masks, gloves and PPE should be discarded in regular trash, and if someone in the household shows any COVID-19 symptoms, all the material should be disposed of with the regular trash, wrapped in two layers of plastic bags. *Jaqueline Sordi is a Brazilian journalist and biologist, specializing in science and environmental journalism. She has a master’s degree in environmental journalism at UCLA and is currently a Ph.D. candidate in communications at Federal University of Rio Grande do Sul.

By Jaqueline Sordi* In November 2021, all eyes will be on Glasgow, Scotland when the city will have a chance at fame as the venue of a major environmental success—or bitter failure. For twelve days, Glasgow will receive leaders from 200 countries as host of the twenty-sixth UN Climate Change Conference of the Parties (COP26). These are anticipated to be the most pivotal climate talks since Paris in 2015 (COP21) when almost every nation on Earth signed the Paris Climate Agreement and committed to limiting the rise of global average temperature to “well below 2°C.” COP26 will be the first conference convened after the measures agreed upon in Paris take full effect. The event, originally scheduled to take place last year, was postponed due to the COVID-19 pandemic. Since then, it has generated high expectations and concern among the scientific community, climate activists, and government officials around the world. After all, while the Paris Agreement was considered a great success in global climate action for its ambitious goal, progress towards meeting this goal has since been painfully slow. With ice caps melting faster, tropical storms becoming more common, and temperatures rising across the globe, environmentalists say that this could be our last chance to avoid environmental devastation. According to the latest studies, global greenhouse gas (GHG) emissions will need to drop by half by 2030 and reach “net-zero” around mid-century if the worst climate impacts are to be avoided. Net-zero is the point when all GHG emissions released by humans are offset by extracting GHGs from the atmosphere through carbon removal processes. So, what needs to happen to make this climate summit a success? Climate specialists specify some important goals to be achieved: countries need to present more ambitious climate goals, the richest nations (also known as the G7 group) need to commit to international climate financing, and the parties need to finalize topics in the Paris Agreement rulebook that are still pending. 1. Ambitious Emission Reduction Targets Six years ago in Paris, a number of countries agreed to submit their climate commitment goals (known as nationally determined contributions, or NDCs) to the UN and update them every five years. The idea sounded great. After all, this was an effective way to monitor the world’s progress towards meeting the overall goal of the climate agreement. However, in February 2021 the UN reported that the countries were falling short of their emission reduction commitments and were “nowhere close” to the level of action needed to fight global warming. The document examined 48 NDCs submitted by 75 parties by the end of 2020 and found that the commitments made would only cut emissions by about 2.8% of what had been pledged by those countries five years earlier. “The aggregate effect of the CO2 reduction targets contained in those documents is generally consistent with emission trajectories that result in global warming of around 3°C by 2100, with warming continuing afterward,” explains Thelma Krug, Vice-Chair of the Intergovernmental Panel on Climate Change (IPCC). The biggest polluters and the richest countries need to drastically increase their emission reduction targets and present concrete timelines to act. Policy, technology, and behavior need to shift across the board. The UN reported that countries are “nowhere close” to fulfilling the climate goals made in Paris. In fact, current national commitments will only cover 2.8% of what was pledged in 2015. “This implies a transformation in all sectors of the economy, something unprecedented in history. CO2 is the most abundant greenhouse gas in the atmosphere and is present in practically all areas of the economy: in industry, in land use (particularly with deforestation and forest degradation), in energy supply, in transport. So, zeroing these CO2 emissions requires the implementation of profound emission reduction measures that, in case they are not zeroed around 2050, could be offset by the removal of CO2 from the atmosphere through, for example, reforestation," summarizes Krug. Alok Sharma, president of the UN COP26 climate summit, said that, for the November talks in Glasgow to be considered a success, governments also must announce an end to new coal power plants and commit to phasing out existing ones. So far, the G7 countries have agreed to stop international financing of coal projects that emit carbon by the end of this year and phase out such support for all fossil fuels. Sharma is also urging countries to end the sale of new gasoline and diesel vehicles. “Over this year we want to see countries making ambitious commitments on ending the sale of new gasoline and diesel vehicles,” he wrote in an official statement. 2. Climate Financing for Vulnerable Countries Vulnerable nations are the least responsible for climate change, but they are often the most affected by its impacts, like hurricanes, floods, diseases, and more. That is why the executive secretary of the UN Framework Convention on Climate Change, Patricia Espinosa, told global leaders that “international financing has really become one of the most important elements to ensure a good outcome at COP 26.” She was referring to the commitment, made in 2009 by developed nations, to raise climate financing for vulnerable countries to green their economies and adapt to the impacts of climate change. The plan called for nations to mobilize $100 billion per year in climate funds for developing countries starting in 2020 through 2025. The world’s richest nations pledged to financially support vulnerable nations’ adaptation to climate change. So far, almost all have fallen short of those promises. But the world’s richest nations have consistently failed to keep their financial promises. The most recent numbers suggest that they are falling short of that goal by $20 billion a year. A report by the Danish charity Care International found that only three countries—the UK, New Zealand, and Luxembourg—have announced concrete plans to increase their disbursements. Although the G7 leaders, at their latest summit, reaffirmed their intention of “increasing and improving climate finance by 2025,” they did not reach an official agreement. “We need to have an increase in the scale of climate finance and the assurance that the resources will be available to developing countries, especially now, when they have been and are still being affected not only by climate change but also by the COVID-19 pandemic. These countries will only be able to act and establish development policies based on emission-reducing projects if they have external support,” explains Carlos Rittl, a Brazilian environmentalist who works at the Institute for Advanced Sustainability Studies in Germany. 3. Finishing Touches on the Paris Rulebook The Paris Agreement was signed five years ago, but some important details of the Paris Rulebook (the Agreement’s implementation guidelines) have yet to be finalized. This is expected to be done at COP26. There are three main topics that have been discussed in parallel events since 2015 but are still open for negotiation. The first covers the technical details of the rulebook’s enhanced transparency framework which includes standards for how countries will track and report their greenhouse gas emissions. Secondly, the parties need to set a common time frame and corresponding targets for their 2025 NDCs. And the last topic to resolve at COP26 is determining how carbon markets (Article 6 of the Paris Agreement) will work. There is still disagreement on the rules governing how global carbon markets will function. Leaders are expected to coordinate plans to ensure an overall mitigation of global emissions while, at the same time, avoiding the double-counting of emission reductions. As the UN climate chief, Patricia Espinosa, said in June, a “significant amount of work” lies ahead for the COP26 summit. *Jaqueline Sordi is a Brazilian journalist and biologist, specializing in science and environmental journalism. She has a master’s degree in environmental journalism at UCLA and is currently a Ph.D. candidate in communications at Federal University of Rio Grande do Sul.

By Jaqueline Sordi* Two of the lead authors of the Intergovernmental Panel on Climate Change's (IPCC) new report explain how global warming is affecting the ocean—and all of us. The whole planet is observing drastic, unprecedented changes in the Earth’s atmosphere, oceans, and polar regions that are unequivocally a result of human activities. In fact, some of these changes that have already been set in motion—such as continued sea level rise—are irreversible. This is just a sampling from the main conclusions of the latest Intergovernmental Panel on Climate Change (IPCC) Report, released last August, 2021, in which 234 scientists from around the globe summarized the current climate research on how the Earth is changing as temperatures rise and what those changes will mean for the future. Some of the most concerning conclusions of the report relate to the impacts of global warming on the oceans, which cover almost three-quarters of Earth’s surface, and the cryosphere (frozen water portion of the Earth covering another 10%). According to climate researchers, the global sea level has been rising at an accelerating rate since about 1970, and, over the last century, it has risen more than in any other century in at least 3000 years. These changes are already affecting all people on Earth, but especially those in the Arctic, low-lying coastal zones and high mountain regions. As a result of impacts to the ocean and cryosphere, communities around the world are already seeing their water resources disappear, experiencing floods and landslides, facing changes in food supply, and witnessing the degradation of ecosystems, infrastructure, recreation, and culture. According to IPCC projections, the intensity of these and other impacts will depend on what actions the global community takes today to reduce emissions. Jaqueline Sordi, on behalf of The Earth & I, interviewed Dr. Aimee Slangen** and Dr. Helene Hewitt***, two of the lead authors of the report’s chapter on Earth’s oceans, ice, and sea level rise, about the profound changes underway. Could you describe the IPCC report’s latest assessment on the state of the ocean? Dr. Helene Hewitt: The ocean has warmed, which has contributed to sea level rise since water expands as it becomes warmer. The ocean has become more acidic and the area of sea ice in the Arctic is reducing. We have also seen an increase in extreme events in the ocean including marine heat waves and coastal flooding. Ocean warming, ocean acidification, and sea level rise are all projected to continue over this century. Dr. Aimee Slangen: The global heat content of the ocean has increased since at least 1970 and will continue to increase over the 21st century. The Greenland ice sheet, the Antarctic ice sheet, and the glaciers around the world have lost mass over the observed period, and this will continue throughout this century. The sea level will continue to rise through 2100 because all contributors (including ocean warming and the loss of ice mass on land) will continue throughout this century. How and why are these assessments different from previous reports? Dr. Hewitt: In this report the assessment shows that the changes we have seen in recent decades are unprecedented. The report has a greater focus on changes in extremes and assesses the regional changes that have been and will be experienced. Dr. Slangen: There is again more evidence showing the changes, and we have better models to project future changes. As a result, this report is a refinement with more details than the previous report. What's the report's most important overall message in terms of ocean changes? Dr. Hewitt: The latest IPCC report confirms that the climate system, including the ocean, has experienced widespread, rapid, intensifying, and unprecedented changes. While deep and rapid reductions in emissions will limit climate change in the near surface, the deep ocean responds slowly, so some changes in the ocean that have already occurred will be irreversible for centuries to millennia. Dr. Slangen: We know that the ocean is warming and that sea level is rising. The rate of sea level rise in the 20th century was faster than in any century in the past 3000 years, seeing as it has risen over 20 centimeters (almost 8 inches) since 1900. Sea level will continue to rise, but the speed is strongly determined by the amount of greenhouse gas emissions and how fast they can be reduced. At the current rates, how much sea level rise is now considered unavoidable? Dr. Slangen: Even if greenhouse gas emissions are reduced completely and quickly, we expect a sea level rise of about 40 centimeters (almost 16 inches) by the end of the century. This is because the processes that cause sea level rise, such as ocean warming or ice sheet melt, will not respond immediately. It will take time before they adjust and find a new equilibrium. On the other hand, if there are no emission reductions, we expect a sea-level rise of about 80 centimeters (over 31 inches). It could even be more than a meter (over 39 inches) if accelerated ice mass loss on Antarctica takes place. So, what we do right now will impact the sea level rise in the long term and, specifically, the rate of sea-level rise. We have to ask the question: Will it be the current rate of 4 millimeters per year, or will it be much more? What are you most concerned about occurring, avoiding, or preventing in regards to changes to the ocean or ice as a result of global warming? Dr. Slangen: We are most concerned about Antarctica, because there is a gigantic amount of freshwater stored in the ice sheet. To give a sense of the scale, if the Antarctic ice sheet were melted completely, that would translate to 58 meters or 190 feet of sea-level rise. While a complete melt is not something that could happen on a human timescale, parts of the ice sheet may experience a ‘runaway’ effect due to ice sheet and ice cliff instabilities if we keep warming the climate. It is however a very difficult place to do research in, so we don’t yet have all the knowledge we would like about [the state of the ice in] Antarctica in order to exactly say how much, how fast, and when we would expect large contributions [towards sea level rise] from Antarctica. Is there a “maximum” sea level rise scenario if global warming continues unabated? Dr. Hewitt: In the assessment, we look at a worst-case scenario. This would only occur if the world followed a high emissions pathway, eventually leading to a large loss of ice from the Antarctic ice sheet over the next centuries. We can’t exclude the possibility of sea level rise approaching 2 meters (over 6 feet) by 2100. Is it still possible to avoid a catastrophic scenario? If so, what could we do? Dr. Hewitt: The science is clear: while some sea level rise is unavoidable, deep and rapid reductions in emissions will limit the warming of the ocean and the melting of ice sheets and glaciers—all of which contribute to sea level rise. This is our best chance of limiting sea level rise over this and future centuries. Dr. Slangen: I agree with Dr. Hewitt. What the planet needs is rapid, strong, and sustained greenhouse gas emission reductions. *Jaqueline Sordi is a Brazilian journalist and biologist, specializing in science and environmental journalism. She has a master’s degree in environmental journalism at UCLA and is currently a Ph.D. candidate in communications at Federal University of Rio Grande do Sul. **Dr. Aimee Slangen is a researcher at NIOZ Royal Netherlands Institute for Sea Research, Department of Estuarine and Delta Systems, and Utrecht University Netherlands and one of the lead authors of Chapter 9 of the IPCC Sixth Assessment Report on “Ocean, cryosphere, and sea level change.” ***Dr. Helene Hewitt is a coordinating Lead Author of the Ocean, Cryosphere and Sea Level Change chapter and Science Fellow at the Met Office Hadley Centre in the United Kingdom.

By Jaqueline Sordi* Considered a “failure” by climate activists such as Greta Thunberg and a “success” by some world leaders, the UN Climate Conference (COP26) held in Glasgow, Scotland, from October 31 to November 13, 2021, made important progress toward reducing the impact of global warming but did not keep the world on track to beat back the climate crisis. The two-week meeting that gathered a record number of delegates in the Scottish city was surrounded with expectations and tensions after being postponed due to the COVID-19 pandemic and after the release of the latest Intergovernmental Panel on Climate Change's (IPCC) report. According to the report, published in August 2021, climate change is widespread, rapid, and intensifying, and some trends are now irreversible. However, scientists claimed there is still time to limit the worst scenarios with strong and sustained reductions in emissions of carbon dioxide (CO2) and other greenhouse gases. In the Glasgow Climate Pact (the final document produced at the end of COP26), almost 200 countries made commitments to reduce the use of fossil fuels, but specialists claimed the pledges are still insufficient. Thelma Krug, Vice-Chair of the IPCC, explains that one of the positive outcomes from the conference was that this was the first-ever COP to openly discuss fossil fuels, calling for a “phasedown of unabated coal” and “phase-out” of “inefficient” fossil-fuel subsidies. “This was the first time that fossil fuels, mostly coal, have been explicitly addressed in a COP agreement. The expectation was to close a deal calling for the "phase out" of coal-fired power, but, in the end, they replaced it with the term "phasedown." Even so, we can still consider it a step forward,” explains Krug. Here we provide a summary of the key outcomes in Glasgow. Defining the Rules of the Paris Agreement After almost six years of negotiation, nearly 200 countries finalized the outstanding elements of the Paris Agreement at COP26. The Paris Rulebook, the guidelines for how the Paris Agreement is to be delivered, was discussed during the two-week meeting in Glasgow, and, on the last day, the final document was presented with important progress, such as a deal on Article 6, which covers international cooperation, including carbon markets, and establishes a robust framework for countries to exchange carbon credits through the UNFCCC. Negotiators agreed to avoid the double-counting of emissions, in which more than one country claims the same emissions reductions as counting toward their own climate commitments. They also established a common time frame for their national climate commitments, encouraging countries to align new Nationally Determined Contributions (NDCs) targets’ dates around five-year cycles. Mobilizing International Finance for Vulnerable Nations The amount of money rich countries should give to the developing world to help it cope with climate change was one of the big battles of the COP26 climate summit, and once again the UN meeting frustrated leaders from vulnerable nations. In 2009, developed countries made a commitment to raise climate financing for developing nations to green their economies and adapt to the impacts of climate change. The plan called for nations to mobilize $100 billion per year in climate funds for developing countries starting in 2020 through 2025. Just before COP26, however, rich nations acknowledged that they could not keep their financial promises (only 80% has been delivered) and would not be able to do so until 2023. The expectation was that a better agreement would be made in Glasgow. However, after two weeks of discussion, the final text of the Glasgow Climate Pact noted “with deep regret” that developed countries failed to meet that goal and “urged” those nations to meet the target “urgently and through to 2025” but lacked any wording on making up the shortfall that has already accrued. Additionally, little progress was made on current loss and damage, in which rich countries could help other nations deal with the climate impact they're already experiencing. For some specialists, COP26 will be remembered as a betrayal of global south countries, who have been left with no money for energy transition or adaptation to the climate crisis. Reducing Emissions to Stop Warming at 1.5°C Before the Paris Agreement was signed, the world was on a dangerous trajectory to reach about 4°C of warming by 2100. The 2030 climate plans prepared by nations ahead of COP26 were not ambitious enough to limit warming to 1.5°C. Instead, they would result in the planet warming by about 2.7°C by the end of the century. Further, in February 2021, the UN reported that most nations were already falling short of their emission reduction commitments. The United Nations calculated that the climate commitments made during COP26 put the world on track for 2.5°C of warming by the end of the century, way above the goal of limiting the rise of global average temperature to “well below 2°C” signed in Paris. That is why Alok Sharma, president of the UN COP26 climate summit, said that, for the November talks in Glasgow to be considered a success, governments needed to announce stronger commitments and stick to their plans. After the Glasgow meeting, more than 150 nations submitted new Nationally Determined Contributions (NDCs) containing more ambitious climate goals. The summit also saw a steady stream of net-zero targets from countries promising to balance emissions and CO2 removals by mid-century. By the close of COP26, a total of 74 targets were communicated. India has said it will reach net-zero carbon emissions by 2070. This is decades later than many other countries, but this announcement marks the first time the country has put an end date on its contribution to climate change. Results of Conference: Not Good Enough While these targets are good news, they are not good enough. The United Nations calculates that the new NDCs, as they stand, put the world on track for 2.5°C of warming by the end of the century, way above the goal of limiting the rise of global average temperature to “well below 2°C” signed in Paris. According to Carbon Brief, if countries stick to their NDC goals and meet their long-term net-zero promises, global warming would be reduced to around 1.8°C (an estimated range of 1.4°C to 2.6°C) by 2100, although temperatures would likely peak around 1.9°C in the middle of the century before declining. The small positive steps that COP26 has brought must be just the beginning of more ambitious climate achievements. “It is an important step but is not enough. We must accelerate climate action to keep alive the goal of limiting global temperature rise to 1.5 degrees,” said the Secretary-General of the United Nations António Guterres in a video statement released at the close of the meeting. He also added that it is time to go “into emergency mode,” ending fossil fuel subsidies, phasing out coal, putting a price on carbon, protecting vulnerable communities, and delivering the $100 billion climate finance commitment. “We did not achieve these goals at this conference, but we have some building blocks for progress,” he said. That is why, looking past COP26, climate activists, scientists, and all citizens need to pressure world leaders to reduce our reliance on fossil fuels, to ramp up their 2030 emissions reduction targets, and to stick to the promises already made. Some of this progress towards more climate ambition might be clearer next year, at COP27, set to take place in Egypt. *Jaqueline Sordi is a Brazilian journalist and biologist, specializing in science and environmental journalism. She has a master’s degree in environmental journalism at UCLA and is currently a Ph.D. candidate in communications at Federal University of Rio Grande do Sul.

By Jaqueline Sordi* Last year, the Intergovernmental Panel on Climate Change (IPCC) released their latest report confirming what we have all been experiencing in different levels around the world: The Earth is warming at unprecedented rates as a result of human activities, bringing with it more extreme weather, floods, less predictable seasons, and changes in worldwide air and ocean circulation. Scientists say that to preserve a livable climate, greenhouse gas (GHG) emissions must be reduced to net zero by 2050, and that bold, fast, and wide-ranging action needs to be taken by governments, businesses, and all citizens. A few months later, at the 26th UN Climate Conference (COP26), held in Glasgow, world leaders failed again to make bold commitments towards the reductions in emissions of carbon dioxide (CO2) and other GHGs, but there is still hope. Individuals can be important drivers to solve this climate crisis, not only by adamantly demanding urgent actions from their politicians and institutions but also by making choices that have less harmful effects on the environment. “Personal actions are important for the impact they can have on those around us by encouraging friends and family to change their behaviors, businesses to amend their practices or elected officials to implement pro-environmental policies,” says Dr. Neil Jennings, Partnership Development Manager at the Grantham Institute–Climate Change and the Environment at Imperial College London. “Many climate actions also provide benefits to our health—whether via improved air quality from reducing car use or reducing the risk of cancer and heart disease from reducing meat consumption and moving toward a more plant-based diet,” he adds. So, what can you do that will have the biggest impact? Here we show you five simple and realistic ways you can help fight climate change. 1. Changing Your Diet Meat and dairy account for around 15% of global greenhouse gas emissions, so avoiding meat (or eating fewer portions of meat) and shifting to a more plant-based diet is one of the biggest ways to reduce your environmental impact on the planet. “By eating a little less of the climate impactful foods like ruminant meat and animal-based products, people can help to reduce their climate footprints,” explains Edwina Hughes, the Head of the Cool Food Pledge at World Resources Institute (WRI). “Try to choose fresh, seasonal produce that is grown locally to help reduce the carbon emissions from transportation, preservation, and prolonged refrigeration.” Studies suggest that a high-fiber, plant-based diet is also better for your health—so it can be a win-win. Try to choose fresh, seasonal produce that is grown locally to help reduce the carbon emissions from transportation, preservation, and prolonged refrigeration. And, if you make this smart choice, you are not alone. “Meat Free Monday” is a global initiative to encourage people to have a healthier diet and save animals and the planet at least once a week. 2. Walking and Cycling Transport accounts for around a quarter of all greenhouse gas emissions in the world, and road travel accounts for three-quarters of transport emissions. Most of this comes from passenger vehicles—cars and buses—which contribute 45.1%. Therefore, consider leaving the car at home and walking and cycling or using public transport, when and where possible. If the infrastructure is not in place to walk and cycle, contact your elected officials to ask them to make the necessary changes. This can be a life changer for you and your community. In Waltham Forest, Northeast London, the council ran a project called “Mini-Holland” to encourage people to travel via more active forms of transport to improve air pollution and reduce GHG emissions. Through a combination of cycle lanes, road closures, and cycle training, they helped create an environment where walking and cycling were the norm. Over three years, car ownership decreased by 7%, street crime reduced by 18%, and there was a 75% reduction in the risk of being injured in a road traffic collision. Also, research by King’s College London estimated that, as a result of the cleaner air caused by the project, the local population could gain around 41,000 life years over the next century. The success of the project led to nearby neighborhoods contacting the council to ask if they could be provided with similar infrastructure as well. 3. Changing Your Home Take a good look at your house and see what you can do to help the environment. The costs of reducing your home's carbon footprint can vary from a few dollars for better draft-proofing or using low-energy lightbulbs, to hundreds of dollars for renewable energy generation, such as whole-house insulation systems. Here you can find 101 tips to make your house a more environmentally friendly place. 4. Flying Less The COVID-19 pandemic showed us that it is possible to meet remotely for meetings or even a big conference. So, if you need to gather with others for business, consider using video-conferencing instead. Around 2.4% of global CO2 emissions come from aviation. Together with other gases and the water vapor trails produced by aircraft, the industry is responsible for around 5% of global warming. It might not seem much, but just one flight from London to San Francisco, for example, emits around 5.5 tons of CO2 equivalent per person—more than twice the emissions produced by a family car in a year. When flying is unavoidable, keep the emissions to a minimum by reducing the weight of your luggage, choosing the most environmentally friendly airplanes and paying a little extra for carbon offsetting. 5. Spreading the Word Encourage your friends, family and co-workers to reduce their carbon pollution. Join global movements such as Fridays for Future, contact your member of Congress or the Senate. Ask them to support climate legislation. You can also send a signal to the market that people want zero-carbon alternatives. If you buy local and choose products committed to contributing to a more sustainable future, you will stimulate the industry to this new deal. Also, never stop learning about new ways to help reduce emissions of CO2 and other greenhouse gasses. *Jaqueline Sordi is a Brazilian journalist and biologist, specializing in science and environmental journalism. She has a master’s degree in environmental journalism at UCLA and is currently a PhD candidate in communications at Federal University of Rio Grande do Sul.

By Jaqueline Sordi* 2022 has been a year of extreme weather events worldwide, resulting in humanitarian disasters with thousands of deaths and hundreds of displaced communities. Fortunately, help is in sight for poorer nations to mitigate the resulting damage and to build up climate change resilience. The United Nations Framework Convention on Climate Change Conference of the Parties (COP27) concluded on November 20 in Sharm el-Sheikh, Egypt, with the establishment of a historic loss-and-damage fund to help poorer nations tackle climate change. Nevertheless, the conference fell short on goals to fight global warming and make progress on commitments to phase out fossil fuels. These goals were expected to limit a possible global temperature rise this century to “well below 2 degrees Celsius [above pre-industrial levels] and to pursue efforts to limit the temperature increase even further to 1.5 degrees.” This is one of the key objectives around which the 2015 Paris Agreement was formed at COP21, and so it has become shorthand for the success of every subsequent climate summit. This latest round of UN climate talks gathered more than 35,000 people from almost every country in the world. The two-week meeting was held against a backdrop that included an energy crisis propelled by the war in Ukraine and scientific data reiterating that the world is not doing enough to tackle carbon emissions and protect the future of the planet. Today, national pledges to tackle climate change could lead to around 2.4 °C of global warming this century, far above safe levels. According to the latest report of the Intergovernmental Panel on Climate Change (IPCC) 2022, limiting global warming—preferably to 1.5 °C—is the only way to avoid the worst impacts of climate change, but this would require rapid, far-reaching, and unprecedented changes in all aspects of society. Today, national pledges to tackle climate change could lead to around 2.4 °C of global warming this century, far above safe levels. “Humanity has a choice: Cooperate or perish. It is either a Climate Solidarity Pact—or a Collective Suicide Pact,” United Nations Secretary- General Antonio Guterres said in his COP27 opening remarks. Historical Agreement on ‘Loss and Damage’ As the world gets hotter, extreme weather events such as more intense and frequent heat waves, droughts, wildfires, and floods already threaten human physical and mental health, but some socially and economically disadvantaged groups face the greatest risks. According to data from the Sixth IPCC report, in more vulnerable regions of the world—such as the small Oceanic Islands, the Caribbean, Southeast Asia, Central America, West Africa, and Central Africa—mortalities caused by extreme weather events were fifteen times higher in the last decade than in regions more adapted to climate impacts. That’s why developing countries have been seeking financial assistance to rescue and rebuild the physical and social infrastructure of areas devastated by extreme weather. This year, for the first time, this issue was on the official COP27 agenda. By the end of the meeting, more than 190 countries agreed to establish a fund for loss and damage. “This represents a significant step forward in the global fight against the climate emergency,” said Achim Steiner, administrator of the UN Development Programme. But the final text of the Sharm el-Sheikh Implementation Plan remained vague, with no guidance on how much money the fund needs or who will pay into it. No Progress on Fossil Fuels ‘Phase Out’ The burning of fossil fuels accounted for 86% of all greenhouse gas (GHG) emissions between 2011 and 2021, according to the IPCC. Last year at the COP26 in Glasgow, countries committed to phasing down the use of coal. It was the first time a resolution on fossil fuels had been included in the final text, but environmentalists and scientists subsequently criticized it for not meeting the goal of the Paris Agreement. The COP27 final text disappointed, with no progress to include a commitment to phasing out all fossil fuels. This year, many people expected countries to go further and include a commitment to phasing out all fossil fuels, but the COP27 final text disappointed, with no progress on this issue. Some observers said the lack of progress on fossil fuels was not a surprise, given that a record number of fossil fuel lobbyists—636 people, according to advocacy group Global Witness—attended this year’s event No Aggressive Move To ‘Keep 1.5°C Alive’ Science has proven it is still possible to meet the 1.5 °C target, beyond which disastrous climate impacts are believed to lie. But to achieve that goal, countries need to act aggressively and quickly, while reducing GHG emissions by 50% by 2030. Although this issue was debated until the very last minute, the final UN COP27 climate summit text fell short on efforts to lower GHG emissions and did not mention additional curbs on fossil fuels. Reduction of greenhouse gases remains voluntary. Ambiguous Resolution on ‘Low-emission Energy’ The final text of the COP27 implementation plan emphasized the need for a rapid reduction in global GHG emissions “through increase[s] in low-emissions and renewable energy,” but little was offered in the way of specifics. Experts say the elasticity of the language keeps the door open to some fossil fuels, such as natural gas, being considered part of a green energy future. Critics say that while natural gas is a cleaner-burning resource than coal and liquid petroleum, it still emits large amounts of carbon into the atmosphere in the form of both CO2 and methane. Overall, COP27 accomplished something historic with the new loss-and-damage fund. If it is properly financed, the most-vulnerable countries will have gone home as the winners. But fighting symptoms is not enough, and many observers chided this year´s climate summit for failing to deal with the factors causing climate change. Experts say the world is running out of time to avoid the worst-case scenarios of global warming. According to Natalie Unterstell, president of the Talanoa Institute, a climate policy think tank in Brazil, “it is necessary that governments and their diplomats assume ambitious commitments” to advance technological and financial change and increase public support for decarbonization in their countries. *Jaqueline Sordi is a Brazilian journalist and biologist, specializing in science and environmental journalism. She has a master’s degree in environmental journalism at UCLA and is currently a Ph.D. candidate in communications at Federal University of Rio Grande do Sul.

By Jaqueline Sordi* In March 2023, heavy rains affected 40,000 people living in the northern Brazilian state of Acre, with up to 10,000 being displaced across the state. A week earlier, Cyclone Freddy made landfall in southern Africa, forcing 80,000 Africans to move away from home. The month before, almost 50,000 were looking for a new place to live after a flood in Malaysia. Going hungry because of a drought, losing a home due to a devastating flood, or being forced to move due to desertification or rising sea levels might seem a distant scenario to some people. Still, it is already a reality for millions of communities living on the frontlines of the climate crisis. Known as “climate refugees,” they are experiencing the worst impacts of a warmer world. And as the threat of climate change increases globally, their numbers are expected to grow exponentially. The term “climate refugees” refers to people who must leave their homes and communities because of the effects of climate change on their environment. It was coined in 1985 as a report title for the United Nations Environment Programme (UNEP), and reinforced in 1990 by the publication of the First Assessment Report of the Intergovernmental Panel on Climate Change (IPCC). Back then, scientists claimed that “the gravest effects of climate change may be those on human migration as millions will be displaced.” What they couldn’t predict is that it wouldn’t take long for this scenario to happen. According to UNHCR, the United Nations refugee agency, “since 2008 an annual average of 21.5 million people have been forcibly displaced by … floods, storms, wildfires, extreme temperatures,” and other events. Scientific studies indicate that the intensity and frequency of extreme weather events have increased over the past twenty years. As a result, according to UNHCR, the United Nations refugee agency, “since 2008 an annual average of 21.5 million people have been forcibly displaced by … floods, storms, wildfires, extreme temperatures,” and other events. By 2050, the Institute for Economics and Peace (IEP) estimates that there could be 1.2 billion climate refugees. To put this into perspective, over 15% of the world’s population is unable to live in their homeland, due to the impacts of changing climate. Lack of Protection Currently, there’s no international law to protect those displaced communities, making them invisible for many years in the migration and climate debates. And there’s still no widely agreed-upon definition for “climate refugee,” even though this term was recently added to the Oxford Dictionary. Most displaced communities are not even recognized as refugees under the terms of the 1951 Refugee Convention, meaning that states have no legal obligation to grant them entry. Therefore, climate refugees may be returned to their shattered homelands or placed in a refugee camp. “People displaced for reasons linked to climate change may only fall within the legal definition of refugee in limited circumstances, for example, where effects of climate interact with conflict, violence, human rights abuses, and persecution.” “People displaced for reasons linked to climate change may only fall within the legal definition of refugee in limited circumstances, for example, where effects of climate interact with conflict, violence, human rights abuses, and persecution,” says Natalie Schmidthaeussler, Office of the Special Advisor on Climate Action (UNHCR). It is also important to note that the term refugee is defined as a person who has crossed an international border; nevertheless, most people displaced by disasters and the adverse effects of climate change stay within their own countries. That’s why some agencies prefer to call them “climate migrants.” For the International Organization for Migration (IOM), “climate migration” is considered a subcategory of “environmental migration,” a broader definition for people forced to flee their homes because of naturally occurring disasters, such as erupting volcanoes and tsunamis. Despite a lack of agreement over its definition, the term “climate refugee” has gained popularity in recent years and is now used by politicians, international organizations, NGOs, academics, and media outlets. And while no legal, internationally accepted definition for persons on the move due to environmental drivers exists to date, the good news is that international governments are starting to recognize climate migration as an issue that needs to be tackled. A Matter of Climate Justice At COP27, the 27th UN Climate Change Conference held in Egypt in November 2022, governments agreed that poor countries afflicted by climate breakdown should receive funds for “loss and damage” to help them recover and rebuild after extreme weather. Details on how the new global fund should operate are still to be worked out this year, but it must include some form of provision for migration. This was a significant step towards the claims for “climate justice,” since it’s now well known that poorer nations face greater risks from climate change and are less able to adapt to them. In fact, many—but not all—climate refugees come from countries in sub-Saharan Africa, South Asia, and Latin America. According to Schmidthaeussler, the challenges faced by the governments of climate-vulnerable countries are immense; but many well-tested tools can assist: “Existing refugee and human rights instruments provide an important framework to support action that protects people displaced across and within borders. To avoid the worst outcomes, additional finance and support must be delivered at the scale and speed required to reach those who need it most.” The Need for Climate Resilience While reducing greenhouse gas emissions and protecting climate refugees with the help of the international community must be priorities for governments committed to fighting the climate crisis, strengthening the resilience of communities and ecosystems vulnerable to climate-induced hazards should also be a prime concern. “Not every climate event is a disaster; it depends on where it happens. That’s why this is a matter of climate justice, and the solution is not to move those communities away from where they live, but to make them resilient to extreme weather events,” says Erika Ramos, co-founder of the South American Network for Environmental Migrations (RESAMA). To protect people living in vulnerable areas, it is crucial to invest in climate adaptation. According to the Center for Climate and Energy, that includes “the ability to anticipate, prepare for, and respond to hazardous events, trends, or disturbances related to climate. Improving climate resilience involves assessing how climate change will create new, or alter current, climate-related risks, and taking steps to better cope with these risks.” According to the latest UNEP’s Adaptation Gap Report 2022, however, countries are not doing enough. The report finds that adaptation planning, financing, and implementation efforts are not keeping pace with the growing risks. To Ramos, one of the reasons is that people who suffer the most are being sidelined in key decision-making processes, and they need to be heard. “Refugees, displaced people, and their hosts are already playing their part in leading local action where it is needed most. They possess knowledge and capacities critical to effective and inclusive climate action. It is important to include them in the decisions that impact their lives. They have a right to participate, and their participation is necessary for lasting resilience,” says Schmidthaeussler. *Jaqueline Sordi is a Brazilian journalist and biologist specializing in science and environmental journalism. She has a master’s degree in environmental journalism at UCLA and is currently a Ph.D. candidate in communications at the Federal University of Rio Grande do Sul.

In our quest to explore the role of nutrition in the restoration of human and environmental health, we sought out an expert on chili peppers, Dr. Ivette Guzman, to set us straight on the healing powers of “heat.” Dr. Guzman is a research scientist at New Mexico State University. Chili Basics As one of the first domesticated crops dating as far back as 10,000 BCE, chili peppers—also known as chile, chilli, peppers, and capsicum—are an extremely valuable and popular vegetable and spice crop from South America. Indigenous populations likely first cultivated chilies for their antibacterial properties[1]. Members of the Solanaceae family and the Capsicum genus, there are thirty-two identified chili species, only five of which have been domesticated: (C. annuum, C. baccatum, C. chinense, C. frutescens, and C. pubescens)[2]. Altogether, there are an estimated 4,000 different chili pepper types worldwide, and each variety is unique in both flavor and level of heat[3]. Indigenous populations likely first cultivated chilies for their antibacterial properties. Nutritional Powerhouses Chili peppers produce medicinal and nutritional compounds important to humans, including vitamins C and E and folate[4]. Among the most important of the biologically active compounds in peppers are capsaicinoids and carotenoids. Capsaicinoids have no color and are alkaloids that bind to heat and pain receptors in humans, while carotenoids are colorful pigments known for being strong antioxidants and providers of Vitamin A[5]. The Spicy Capsaicinoids The purpose of capsaicinoids in peppers is to discourage the consumption of the spicy fruits by mammals, in order to protect the plant’s seeds. Despite this fact, peppers play an important role in the world’s cuisines and in human health. The fruit morphology of peppers, or the forms and structures of peppers, includes the colored fruit wall of the pepper and the colorless placenta membrane that holds onto the seeds. Contrary to popular belief, the seeds are not the location of the spicy capsaicinoids. It is the colorless placenta, in fact, that contains vesicles, or fluid-filled sacs that resemble blisters, which produce and store capsaicinoids. In 2015, Bosland et al. discovered a novel mutation that increases the heat level of peppers by "augmenting the number of capsaicinoid-filled blisters on the fruit wall" in addition to those normally found within the placenta. How Capsaicinoids Work Inside Us Chili peppers make twenty-two distinct capsaicinoids and each one is able to bind to human sensory pain neurons, thus accounting for the heat sensations that chilies are known for[6]. Capsaicin is the predominant capsaicinoid found in chilies, with the remaining twenty-one found in minor amounts[5]. Researchers have discovered that capsaicin acts by binding to a transient receptor potential vanilloid receptor (TRPV). TRPVs are responsible for thermal reactions in the body and are located on nociceptor neurons that are found in almost all parts of our anatomy. Nociceptor neurons alert the brain to threatening stimuli[5]. As a result, capsaicin induces “hot” pain-like sensations in the body. Repeated doses of capsaicin initially induce pain in humans, followed by analgesia, or the inability to feel pain. The Healing Powers of Heat Due to the prevalence of capsaicin in Capsicum species, most capsaicinoid pharmacological studies have focused on capsaicin. Capsaicin is now used orally or as an intradermal and topical application to treat pain. Reports indicate that topical application of eight percent capsaicin produces desensitization, decreasing pain for twelve weeks, and oral capsaicin can be used to treat cough by reducing inflammation of the airways[5]. Capsaicin has also been shown to aid in regulating pro-inflammation in the gastrointestinal tract. It can help patients suffering from stomach pain associated with gastric acid, irritable bowel syndrome, or irritable bladder [5]. In addition, capsaicin may be anti-inflammatory in salivary gland cells and suppress inflammation associated with bile duct cancer, making capsaicin a potential anti-tumor compound. In addition, capsaicin’s anti-inflammatory response in the gastric epithelial cells extends to reducing inflammation generated from H. pylori infections, a common cause of ulcers[5]. It was previously thought that spicy food caused ulcers, however, these results prove the opposite, and could potentially help patients suffering from bacteria-induced ulcers. As with all such studies, it is important to note that the capsaicin dosage was crucial in evaluating its efficacy. It was previously thought that spicy food caused ulcers, however, recent test results prove the opposite, that spicy food could potentially help patients suffering from bacteria-induced ulcers. And What About the Carotenoids? Carotenoids are pigments that are produced in ripening chili peppers. They do not have a flavor, nor are they spicy; however, they are extremely valuable anti-oxidants, some of which are pro-Vitamin A[7]. The important chili carotenoids are two orange carotenoids, beta-carotene and beta-cryptoxanthin, and two yellow carotenoids, lutein and zeaxanthin. Beta-carotene and beta-cryptoxanthin are converted to Vitamin A in the human gut, while lutein and zeaxanthin are absorbed and form the macular pigment designated to protect our eyes’ ocular nerve from harmful blue light oxidation[8]. In general, dark red chili peppers contain high amounts of carotenoids, but could still be void of the pro-Vitamin A, lutein and zeaxanthin. Although we know that colored fruits are good for us, color is still not a good indicator of what type of carotenoids are in the fruits[9]. Even so, we know that consuming spicy and colorful chili peppers is better than limiting consumption to non-spicy, colorful fruits, based on another study[10] where higher amounts of beta-carotene were absorbed by rats being fed beta-carotene and capsaicin together. Measuring the “Heat” Heat intensity, when measured as the total amount of capsaicinoids in a pepper, is generally represented as Scoville Heat Units (SHU), a measurement of heat-level developed by Wilbur Scoville[3]. The hottest chili pepper cultivar, determined by the Chile Pepper Institute, is the Trinidad Moruga Scorpion, surpassing two million SHU. To put that level of heat in context, The SHU for jalapeños ranges from 4,000–50,000, while bell peppers have zero SHU[11]. Heat profiles of peppers that were introduced by Guzman and Bosland[13] in 2017 added to the cultural context of the “burn” within this popular fruit. Chileheads and The Rest of Us A report in 2013 by Lillywhite indicated that spicy chili pepper consumption had doubled in the U.S. from 1980 to 2012[11]. Their research also found that the most popular types of peppers were not necessarily the hottest nor the mildest available on the market, indicating that there are other factors, besides heat, that are driving chili pepper consumption; factors such as flavor, nutrition, and availability. Perhaps the best known, and fastest growing niche of pepper enthusiasm, is populated by the “chileheads,” a grouping of connoisseurs of the “super hot” varieties; peppers with names like bhut jolokia or “ghost chilies.” Chili Breeding for Nutrition The genetics of each pepper dictates its nutritional value; therefore, breeders and food scientists are joining forces to improve chili nutrition. A preliminary step in increasing nutritional value is to discover individual peppers with high amounts of desired compounds, followed by cross-breeding to incorporate the traits into more commonly preferred varieties. In 2016, Kantar screened 101 varieties of chili peppers in search of chilies that could be used to breed for higher nutritional content in other chilies[4]. The group measured pro-Vitamin A, Vitamin C and folate. A similar study was done with capsaicin and SHU amounts in high capsaicin varieties, known as the “super hots”[9]. The goal of these studies was to develop varieties with high nutritional content, like that in NuMex LotaLutein[12]. This cultivar was bred to be rich in lutein which serves to prevent macular degeneration, an eye condition that worsens with age. Chili nutrition research continues to gain attention as scientists learn more about this nutritious, medicinal food crop. Footnotes Cichewicz, R.H., and Thorpe, P.A.1996. “The antimicrobial properties of chile peppers (Capsicum species) and their uses in Mayan medicine.” Journal of Ethnopharmacology 52:61–70. Carrizo García, C., Barfuss, M.H.J, Sehr, E.M., et al. 2016. “Phylogenetic relationships, diversification and expansion of chili peppers (Capsicum, Solanaceae).” Annals of Botany 118:35–51. Guzman, I. and Bosland, P.W. 2017. “Sensory properties of chile pepper heat — and it’s importance to food quality and cultural preference.” Appetite 117:186–190. Kantar, M.B., Anderson J.E., and Lucht, S.A., et al. 2016. “Vitamin variation in Capsicum spp. provides opportunities to improve nutritional value of human diets.” PLoS One 11. Guzman, I. and Bosland, P.W. 2018. “A matter of taste: capsaicinoid diversity in chile peppers and the importance to human food preference.” In Mozsik, Gyula (Ed.), Capsaicin and its Human Therapeutic Development. Rijeka: IntechOpen. Walpole CS, Wrigglesworth R, Bevan S, Campbell EA, Dray A, James IF, Masdin KJ, Perkins MN, Winter J. Analogues of capsaicin with agonist activity as novel analgesic agents; structure-activity studies. 3. The hydrophobic side-chain ‘‘C-region.’’ J Med Chem. 1993;36:2381–2389. Guzman, I., Bosland, P. W., and O’Connell, M.A. 2011. “Heat, color and flavor compounds in Capsicum Fruit.” in The Biological Activity of Phytochemicals. Ed. David R. Gang. Springer, New York. 109–126. Johnson, E.J., Vishwanathan, R., Johnson, M.A., Hausman, D.B., Davey, A., Scott, T.M., Green, R.C., Miller, S.L., Gearing, M., Woodard, J., Nelson, P.T., Chung, H.Y., Schalch, W., Wittwer, J., and Poon, L.W. 2013. “Relationship between serum and brain carotenoids, a-tocopherol, and retinol concentrations and cognitive performance in the oldest old from the Georgia centenarian study.” Journal of Aging Research 2013:951786 Lozada, D.N., Coon, D.L., Guzman, I., Bosland, P.W. 2021. “Heat profiles of ‘superhot’ and New Mexican type chili peppers (Capsicum spp.).” Scientia Horticulturae 283:110088 Veda, S., and Srinivasan, K. 2011. “Influence of dietary spices on the in vivo absorption of ingested β-carotene in experimental rats.” The British Journal of Nutrition 105:1429–1438. Lillywhite, J.M., Simonsen, J.E., and Uchanski, M.E. 2013. “Spicy pepper consumption and preferences in the United States.” HortTechnology 23:868–876. Guzman, I., Coon, D., Vargas, K., and Bosland, P.W. 2020. “NuMex LotaLutein, a high-lutein serrano pepper.” HortScience 55:2052–2055.

By Indrajit Kar and Srinibas Das* Every year the world eats more and more fish. In fact, according to the UN Food and Agriculture Organization, global fish consumption is increasing by over 3% annually. To meet the growing demand, the world’s aquaculture sector is also booming. In 2020, fish farming contributed almost 46% of global fish production. As with other farming sectors, the aquaculture industry has faced concerns about its use of antibiotics and feed. Specifically, questions have been raised about whether intensive aquaculture is harmful to marine ecosystems and to seafood consumers. In response, the aquaculture industry is turning to the use of probiotics to lead its practices toward a more sustainable future. Probiotics: A Boon for Health In 1905, Bulgarian physician and microbiologist Stamen Grigorov discovered a probiotic in yogurt. Decades later, in 1953, German bacteriologist and food scientist Werner Kollath introduced the term, “probiotic,” referring to active, beneficial microorganisms that are “essential for a health development of life.” Today, consumers around the world view probiotics as “live” microorganisms that offer health benefits, especially in the digestive system when eaten or in other ways when applied to the body. Probiotics have also found a purpose in a wide range of industries, including aquaculture. In fish farming, probiotics are mainly used as microbial fish feed supplements to benefit the intestinal microbial balance of the host fish as well as having other benefits. Types of Probiotics: Bacterial and Non-Bacterial In aquaculture, a wide range of bacteria are nurtured for use as probiotics, including gram-positive bacteria—bacteria with thick cell walls—(Bacillus, Carnobacterium, Enterococcus, Lactobacillus) and gram-negative bacteria (Vibrio and Pseudomonus). Non-bacterial probiotics such as bacteriophages—viral parasites of bacteria—are also used in aquaculture. They can alleviate the need for antibiotics while doing no harm to the host. Other non-bacterial probiotics include yeast (Saccharomyces cerevisiae and Yarrowialipolytica), various microalgae (Tetraselmissuecica, Isochrysisgalbana, and Dunaliella salina), and fungi (Debaryomyces), used primarily to supplement protein, lipids, and nutrients in fish feed. These have all been produced and promoted to global markets as environmentally friendly choices for supplementation in aquaculture. Probiotic Sources and Delivery Systems The main source of probiotics for aquaculture is the gastrointestinal (GI) tract of aquatic animals where diversified types of microbes naturally live and colonize. These microbes can be cultured at an industrial scale using what is called batch fermentation in a growth media. The end products are commercially available probiotics in liquid, powder, or microencapsulated form that can be administered as feed additives or added directly to the water in which aquatic species are cultured, or raised. Probiotics are also available in combination with prebiotics—non-digestible beneficial nutritional additives—as well as with immunostimulants or natural plant products. Probiotic-enriched live aquaculture feed—brine shrimp, zooplankton, and small crustaceans—is also regarded as a viable option. The Environmental Effects of Aquaculture Should Not Be Overlooked The growing production of aquatic species, particularly in tightly packed conditions, can have substantial environmental impacts if not managed effectively. Excess and uneaten feed gradually deteriorate the surrounding water quality as microorganisms decompose the uneaten feed, removing oxygen from the water and releasing carbon dioxide in the process. Additionally, when other nutrients including phosphate are released into the water, detrimental algal growth can increase. Antibiotic overuse is another growing problem in aquaculture which produces survivor pathogens that are increasingly difficult to control due to antibiotic resistance. Scientists have estimated that about 80% of the antibiotics applied in aquaculture remain active in the environment, including in waterway sediment. To make matters worse, the guts of aquatic animals contribute to the spread of antibiotic resistant genes in water. The ease of horizontal gene transfer in water allows antibiotic resistant bacteria—the ones that are harmless to humans—to transfer their resistant genes to human pathogens. Probiotics Clean Up Aquaculture in Many Ways Waterways permeated with nitrogen pollution can also suffer from choking algal growth. Organic nitrogen is formed when excess fish feed, feces, and dead fish accumulate in bodies of water as waste from aquaculture. This organic nitrogen is converted by fungi or bacteria to ammonium and ammonia, which are then converted to nitrites, and subsequently from nitrites to nitrates. Through the process of denitrification, these nitrates are converted to nitrogen gas by probiotic fungi or bacteria, thereby returning nitrogen to the atmosphere. Probiotic Bacillus species provide several key benefits for aquaculture. They play an especially important role in this nitrogen cycle through ammonification, nitrification, and denitrification, thereby effecting the elimination of various forms of nitrogen from aquaculture waste water. Additionally, Bacillus species use mineralization and nitrification to modulate pH and dissolved oxygen levels in water. They can even improve fish appetite by increasing the digestive enzymes of fish which results in less feed waste. Probiotics, such as Lactobacillus, have been shown to effectively protect aquatic species against heavy metals. Probiotic Bacillus also converts organic matter effectively into carbon dioxide. The carbon dioxide is then utilized by β- and γ-proteobacteria—a type of gram-negative bacteria—as a carbon source. Whereas other bacteria convert organic matter into slime or bacterial biomass, probiotic Bacillus, in removing organic matter from aquaculture, reduces sludge accumulation. Additionally, as microorganisms decompose excess feed and fish waste and release phosphate that fuels eutrophication, probiotic Bacillus, Saccharomyces, Nitrosomonus, and Nitrobactor reduce phosphate levels in water bodies. Probiotics, such as Lactobacillus, have also been shown to effectively protect aquatic species against heavy metals. Probiotics and Their Contribution to Fish Health The health benefits of probiotics begin in the fish gut, where give-and-take occurs between probiotics, epithelial cells, and the gut immune system. Probiotics actively safeguard against pathogens in the gut by competing for pathogen food sources and by changing the pH in the gut to reduce pathogen growth. Moreover, probiotics enhance the immune system of fish by modulating different immune cells in the fish, including B lymphocytes (a type of white blood cell that produces antibodies), T lymphocytes, and natural killer-cells that kill cancerous tumors and viruses. Probiotics also activate phagocytic cells, types of immune cells that can kill microorganisms, eat foreign material, remove dead cells, and boost immune response. Respiratory burst—an important immune response—can be increased by probiotics. Probiotics can also raise levels of lysosomal enzymes (proteases, amylases, and lipases), thereby removing cell-ingested biomolecular waste and debris from the serum and skin mucosa of fish and allowing nutrients to be absorbed more easily. Probiotic supplementation promotes fish health by producing essential nutrients—like Vitamin B12, biotin, and fatty acids, and may also improve nutrient availability to the fish by increasing the villi size populating the absorptive area of the gut. Furthermore, probiotics have been shown to increase muscle development and growth rate in fish by upregulating growth-related genes and key metabolic enzymes. In addition, probiotics like B.circulans improve flesh quality in fish and increase their protein and beneficial oil content. Probiotic Benefits Far Outweigh the Cons As with any supplement, the benefits of probiotics depend upon dose, duration of feeding, mode of supplementation and environmental conditions. A prolonged or excessive application of probiotics could create immune suppression in fish, making them more susceptible to disease. For instance, recurrent usage of Bacillus subtilis in shrimp aquaculture has been linked to the development of bacterial white spot syndrome (BWSS). Although it is a rather harmless phenomenon, BWSS is difficult to distinguish from white spot viral syndrome, a deadly disease that afflicts shrimp. Having the right knowledge and awareness about the use of probiotics in aquaculture is crucial for probiotics to have the desired effects. Mislabeling or misreading of labels on probiotic products may lead to misuse. Further clarification through research as well as better guidance for producers, middlemen, and farmers is essential; this includes proper instructions for probiotic storage and the monitoring of results. In the long term, whether trying to destroy or encourage microbes via probiotic use, it is important to achieve overall microbial homeostasis, while keeping in mind human, animal, and plant ecosystem health. Future Projections for Probiotics in Fish Farming The ultimate destiny of probiotics is still unknown and requires more study. Ongoing research is working to establish the proper combinations of microbes for the trending aquaculture production systems of today, such as recirculating aquaculture systems and biofloc systems. Specific probiotics are under development to include higher levels of plant materials in aqua feed which may help fish feed more efficiently, grow larger, and stay healthier. Going forward, researchers will need to better classify probiotic strains according to their specific actions, thus permitting a fuller range of products for use. One cutting-edge technique would be to develop specific probiotics or a “cocktail” of probiotics to use with a particular fish species. Finally, having real-time data on pathogen adhesion and colonization in the fish gut as well as applying next-generation sequencing to identify microbes would be helpful in discovering more viable aquaculture probiotics for sustainable food production. *Indrajit Kar, Ph.D., is an assistant professor at West Bengal University of Animal & Fishery Sciences in Kolkata, India. His areas of professional interest include heavy metals in environments, pathology, use of probiotics, and phytomedicinal plants, especially mint. Srinibas Das is an assistant professor in the Department of Fish Nutrition at West Bengal University of Animal & Fishery Sciences in Kolkata, India. He works mainly in areas related to Animal and Fish Nutrition.

By Helen Gavaghan* Never one to let a big idea pass him by, President John F. Kennedy signed an Appropriations Act into law in 1961 to pay for research and development into the extraction of fresh water from saline and brackish water. "There is nothing, really, that we can do in this country that can mean more in the long run to our people and to people all around the world than to be able to make an important and significant breakthrough in this area," said Kennedy. Sixty years later, in the US and globally, safe, energy-efficient desalination remains a key aspiration of governments. Critical to the technology’s success is the need to reduce the energy expended on desalination, as well as to identify safe disposal or even commercial exploitation of brine as a by-product. There are many forms of inorganic matter besides sodium in brackish and seawater. Some can have commercial value. Others simply clog up the equipment. Most extraction of drinking water is in large plants. Smaller desalination centers powered by renewable energy, such as solar or geothermal, struggle to be energy efficient. Yet, such desalination plants could have an important part to play in rural areas where freshwater is scarce but brackish aquifers are present. Patent Granted to Energy-Efficient Desalination Technology What holds solar-powered desalination back is the low energy density in illuminations from the Sun. Ingenious efforts are underway to reduce the effects of that natural limitation. For example, in 2020 a US Patent was granted for a solar-powered method of separating a single cold fluid into at least two flows in an energy-efficient way. Clearly, that type of process could treat seawater to produce drinking water and brine. This patent goes beyond similar earlier efforts of solar-powered desalination. A significant part of the originality in this patent is that the cold seawater is preheated before entering a treatment device by flowing beneath solar panels, while simultaneously cooling those panels. That water then enters a treatment device from which two flows emerge. In a desalination plant, those two flows would be drinking water and brine. In the device described, these two fluids flow back beneath the solar panels through two sets of extensive piping over which the incoming cold water flows. The result is that the incoming seawater is preheated in three ways: by the solar panels and by the separated but warmer desalinated and fresh water in the pipes. Because of the preheating by three heat sources, the treatment device needs less energy than it would otherwise, and the solar panels are cooled, which further improves their efficiency. The patent was granted to Desolenator BV, a Dutch company. The inventor is Wilhelmus Jansen from Abu Dhabi, United Arab Emirates. Water Quality Varies Drastically, Water Insecurity is Widespread The scale of the problem which desalination can contribute to solving is huge. In 2021, twenty-six percent of the world’s population, some 2 billion people, still lack access to safely managed drinking water. In 2020, 771 million people did not have even basic water services. Remedying that situation by 2030 is one of the United Nation’s seventeen Sustainable Development Goals. Unfortunately, the world is not on course to meet the safe-water goal. To achieve its aim, the UN says a four-fold increase in the rate of implementation of water projects is needed, as well as more funding. Importantly, too, the impact of each development goal on the others (energy, food, transport, among others) needs to be assessed. Fresh water is needed for drinking, washing, agriculture, industry, and commerce. For every case, rigorous assessment of water’s organic content and inorganic solutes is important. Freshwater contains fewer than 1000 milligrams of salt per liter, while oceans have on average 35,000 milligrams per liter. Between the two extremes lie brackish waters in aquifers and surface water. Some brackish aquifers are not renewable sources, and scientists still do not know the source of all freshwater aquifers. As water is drawn from brackish sources, they become saltier. Surface freshwaters are found in rivers, sea ice, lakes, reservoirs, wetlands, creeks, and human-made canals. That water is part of the hydrological cycle. Much research remains to be done to understand this complex interconnected set of water resources. Desalination Plants are Growing in Number Throughout the World In the meantime, even with imperfect knowledge, nations are striving to provide safe water. In 2014, there were 16,000 desalination plants in the world, predominantly in Africa and the Middle East. In the intervening seven years, global and regional efforts have kicked in to address freshwater shortages, leading to significant increases in the number of plants. Their capacity ranges roughly from 6 gallons per day to 25 million gallons per day. Although commercial and industrial desalination plants, even small ones, are technically sophisticated, the scientific principles they rely on are well known. Distillation is one key process. Going back to ancient times, it was the first way people extracted usable water from seawater. In essence, brine is left behind when plain water evaporates from heated salty water. The evaporated vapor is condensed to provide drinking water. As knowledge of thermodynamics developed in the 19th century, the methods used in desalination plants to evaporate and condense water under different pressures increased in sophistication. Even modern methods of evaporation and condensation used in today’s desalination plants are open to further advancement. The downside is that energy is lost during phases changes from liquid to vapor and back, which means quite a lot of energy can be wasted. One way of characterizing a desalination plant is to ask how many units of drinking water result from the amount input. That ratio gives the important parameter of the recovery rate. For example, extracting 300 units of drinking water from 900 units of seawater gives a 33.3% recovery. Reverse osmosis is an alternate approach to producing potable water. In osmosis water flows through a semipermeable membrane into a saltier environment. In reverse osmosis, sufficient pressure is applied to overcome osmosis, and water is forced from brine through a membrane which prevents salts from following. Clogging the membrane with inorganic salts can be a problem. Electrodialysis has also been applied for desalination. In this method salts are left behind on charged membranes as water flows through, thereby purifying the water of salts. The method works with brackish water but not with more saline ocean water. Desalination is one of many water purification technologies that needs to be employed if Earth’s abundant water is to be an asset in the fight to provide fresh water to everyone. Now the dilemma is where and how to apply these technical resources for the best outcome for people and their environments. This issue requires input from geologists, hydrologists, and other scientists, as well as political will and economic support from political leaders across the world. Ultimately, we need to protect our water resources and get safe, clean drinking water to where it is needed. *Helen Gavaghan is a freelance journalist, and the founder, editor, and publisher of Science, People & Politics (ISSN 1751598X). She has written and edited for the major international science press and intergovernmental organizations, among others. Helen's books include the first official history of the European Organisation for the Exploitation of Meteorological Satellites and a history of application satellites, praised in Nature for bringing new material to the published literature. She has traveled widely as a reporter and lived and worked in Eindhoven, the Netherlands; London, United Kingdom; and Washington, D.C., in the United States. Helen now works and travels from West Yorkshire, UK.

By Gordon Cairns* For centuries, the humble freshwater mussel has played a crucial role in the daily lives and traditions of the Māori people of New Zealand. Not only are mussels an easy-to-harvest, nutritious food source from local lakes, but the sharp-edged shell has had a variety of traditional uses, from a knife for cutting hair and the umbilical cords of new-borns to a noisy rattle trailing behind children’s kites. It is no wonder that the versatile shellfish has an important position in Māori culture—it is featured in songs, stories, and proverbs. However, this beloved mollusc, known as kākahi in New Zealand, is playing perhaps one of its most important roles yet. Scientists are attempting to harness their incredible ability to steadily filter the impurities out of water to help clean up the country’s slowly suffocating lakes. As it is with many of the world’s waterways, the poor water quality of New Zealand’s shallow lakes is a widespread problem. Data collected from 127 lake sites throughout the country by the research agency, Land Air and Water Aotearoa, showed that more than half of the lakes were categorized as either of poor or very poor quality. Such a dismal situation runs contrary to the country’s international image as a place of clean landscapes and unspoiled environments. This problem is especially apparent in the Waikato region in the upper area of the North Island. A range of factors and environmental changes, from nutrients bleeding into the water from the land to the unwanted establishment of pest fish such as koi carp and catfish, have caused healthy lakes to “flip.” In some of the worst examples, shallow lakes have transformed from clear pools with plentiful aquatic plants to a state in which the water remains permanently muddy or turbid and is dominated by algae. Once a lake has flipped, it can be very difficult for it to be returned to its original state, despite the best attempts made through conventional water management. "International marine biologists have long been aware of the cleansing power of mussels." However, restoration could be at hand. International marine biologists have long been aware of the cleansing power of mussels, nicknaming the shellfish “The Hoovers of the Ocean,” in a reference to the powerful vacuum cleaners. "It's a super-filter in the marine world, filtering up to 25 liters [6.6 gal] of water a day," says marine biologist Leila Meistertzheim, who heads a study for France's Tara Ocean Foundation. New Zealand already has a reputation for innovative approaches to improving its water quality, including the world’s first nitrogen cap for the Lake Taupō catchment over a decade ago. Scientists at the National Institute of Water and Atmospheric Research organization (NIWA) were intrigued to see the impact of a freshwater mussel population on the clarity of water in certain lakes and decided to investigate further. They stated, “Our project was inspired by the observation of abundant mussel populations in small shallow lakes with excellent water quality. This observation made us wonder if freshwater mussels could be part of the restoration process in flipped lakes. The project aim was to harness the filter-feeding capacity of native freshwater mussels on rafts to assist in lake restoration.” Researchers selected Lake Ohinewai, a degraded Waikato lake, to run their large-scale natural filtering experiment. The local Matahuru Marae people welcomed the chance to have mussels reintroduced into their lake and were able to offer expert advice to the scientists. The research team, led by Dr. Deborah Hoftstra, decided to place the shellfish on “rafts,” which looked more like blue plastic bottle crates than the name suggests. These rafts raised the shellfish above the lakebed to a level where there is more oxygen; the additional oxygen helped the mussels to survive longer while also improving the efficiency of their filtration. In pre-trial runs, the team of researchers used a combination oflaboratory and lakeside studies to examine mussel responses to environmental conditions that mussels were likely to experience on rafts in shallow lakes. This information influenced the final designs of the rafts and baskets. In the actual lake filtration experiments, researchers monitored the mussels’ survival and growth aboard the rafts and conducted lakeside studies to examine the localized effects of mussels on water quality. The team used the data to mathematically model Lake Ohinewai and calculate the optimal number of mussels per raft and how many rafts would be needed to significantly impact the water quality of the lake. The researchers did not use naturally born mollusks due to the diminishing stock. Instead, they focused on producing and growing juvenile mussels in a laboratory; these in-house manufactured mussels were used for stocking rafts or re-stocking lakes where the natural species had died out. The team gradually improved the initial high mortality rates in which more than nine out of ten shellfish did not survive beyond two months. After these problems were resolved, the survival rate of mussels placed on all three types of rafts or at the bottom of the lake rose to 97% over the study period of fifteen months. Each experimental raft contained twelve mussel passengers in a basket, with up to eight baskets on a raft. The knowledge and techniques gained during this preparatory phase have aided the design and stocking rates for future trials. By the end of the study period, the researchers discovered that the mussels, feeding on algae, zooplankton, and other microorganisms, were filtering an astonishing amount of water: an approximate flow rate of 1.5 L (0.39 gal) per hour per mussel. Simulations then modelled the positive impacts on the water quality of the lake derived from varying densities of mussels; these positive impacts generally reduced nutrient concentrations, chlorophyll A, and algae. The greatest effect was simulated at more than forty individual shellfish per square meter, compared to the trial situation of two mussels per square meter in only one area of the lake. The study found that mussels can measurably reduce levels of E. coli bacteria from lake water, at a rate of 500 to 24,000 bacteria removed from the water per hour by one hard-working mussel. When one factors in a mussel’s average life expectancy of twelve to thirty years, it is obvious that their introduction could provide long-term natural water filtration with little human intervention. There are now high hopes that future applications of the method can restore New Zealand’s lakes to their pristine glory. The scientists envisage fleets of rafts stocked with thousands of young, farmed mussels bred from surviving resident mussels placed in lakes around the nation. According to Maori mythology, when their Polynesian ancestors made landfall on these uninhabited islands, they brought the mussels with them, trailing behind their boats on long ropes. It seems fitting that over 700 years later, the value of these hardy little shellfish is still recognized by the people of New Zealand. *Gordon Cairns is a freelance journalist and a teacher of English and Forest Schools based in Scotland.