Latest news with #FrontiersinEnvironmentalScience
Yahoo
08-04-2025
- Science
- Yahoo
Trees can snitch on illegal gold miners in the Amazon
Researchers believe they have identified a network of spies to help combat illegal gold mining operations in the Amazon rainforest. But unlike other espionage efforts, there is no risk of betrayal from the new assets: Trees aren't known for spilling secrets. Humans have coveted the Amazon's natural resources for generations, particularly its gold. But with most of the region's easily accessible precious metals long gone, illegal mining operations now focus on extracting the soil's hidden gold particles. To do this, the miners use a method that requires adding toxic mercury into the ground and allowing it to bind to any surrounding gold. Because the resulting amalgams have a much lower melting point than gold alone, miners then burn the mercury away to collect the residual lucrative metal. Meanwhile, the mercury-laden smoke disperses into the atmosphere where it can harm the surrounding environment and local populations. The annual rings inside certain trees near these mines don't just tell their age—they also store important environmental biomarkers over time. Recently, an international team led by researchers at Cornell University wondered if those biomarkers could indicate excess atmospheric mercury levels. To test their theory, experts traveled to the Peruvian Amazon and documented their findings in a study published on April 8 in Frontiers in Environmental Science. Researchers first took core samples from fig trees at five sites. Two locations were far removed from mining activity, but three were within roughly 3.1 miles of mining towns previously known to rely on amalgam burning. One site was also adjacent to protected forest lands. The subsequent analysis results were clear: mercury levels were highest in wood sampled from mining-adjacent sites and lower at those further removed from mines. Additionally, higher mercury levels in mining-adjacent fig trees also coincided with the historical rise in amalgam burning that began after the year 2000. 'We show[ed] that Ficus insipda tree cores can be used as a biomonitor for characterizing the spatial and potentially the temporal footprint of mercury emissions from artisanal gold mining in the neotropics,' Jacqueline Gerson, a Cornell University biological and environmental engineering associate professor and study first author, said in a statement. Although annual tree rings can tell researchers when mercury levels began rising, they can't necessarily offer precise locational directions to the illegal miners. At the same time, higher concentrations may at least serve as reference points indicating a closer proximity. Regardless, the literal spy rings of fig trees may soon offer a cheap, powerful means for regional monitoring and conservation work in the Amazon.
Times of Oman
17-03-2025
- Science
- Times of Oman
Fog harvesting: How to get water from the clouds
Alto Hospicio: Sitting on the fringes of the Moroccan desert, the mountainous region of Ait Baamrane receives little rainfall. But what it does get in abundance, and for six months of the year, is dense fog sweeping in from the nearby Atlantic Ocean. While it might restrict visibility, this misty mass also provides a solution to water shortages. How? It's harvested in the world's largest fog collection system. How does fog harvesting work? Wind pushes water vapour in the air through vertical nets, where it condenses into small droplets that trickle down the netting to be gathered in large containers. The nets collect around 35,000 litres (about 9,200 gallons) of water every day, which covers the needs of more than 1,000 people and is also used to irrigate plants. Fog is not only collected in Morocco's mountains but in other places including Ghana, Eritrea, Ethiopia, Chile, California and South Africa. The global potential is huge with suitable locations almost everywhere, especially along coastlines. Depending on the location, a 40-square-metre (450-square-mile) fog net provides around 200 litres per day. Each one costs around $1,500 (€1,628). Can urban areas also benefit? Until now, fog collection has mainly been seen as a solution for remote rural areas where people are barely connected to the public water network or infrastructure. However, a study recently published in the scientific journal Frontiers in Environmental Science showed that the technology could also benefit cities. With less than one millimeter of rainfall per year, the Atacama Desert in northern Chile is one of the driest places in the world. Cities in the region rely heavily on water from deep underground aquifers that were last replenished between 10,000 and 17,000 years ago. As these ancient supplies are not inexhaustible and because refreshing them takes a very long time, alternative sources are vital. In the town of Alto Hospicio, which lies on the edge of the desert, many of the approximately 10,000 inhabitants live in poverty. Unconnected to the public water network, they rely on trucks to bring supplies to the slums. In search of a solution to the city's water shortage problems, researchers experimented with fog nets both in the urban area and on surrounding hills. On some days they were able to collect as much as 10 litres per square metre, which they say is enough to cover the human consumption and irrigation needs of populations lacking access to public source water. Meeting slums' water needs with fog According to researchers, an average of 2.5 litres of water could be harvested per day and square metre. Using 17,000 square metres of netting, the size of around two and a half soccer pitches, would make it possible to cover the entire water requirements of the slums of Alto Hospicio. Around 110 square metres of netting would be enough to irrigate the city's entire green spaces all year round.
Yahoo
24-02-2025
- Science
- Yahoo
Scientists Want to Farm Fog to Solve the Water Crisis
Researchers may have just found a way to establish a renewable water resource in one of the driest places in the world. Using pieces of mesh, these fog-harvesting machines collect water droplets and funnel them into storage tanks. Fog-harvesting systems aren't just a small-scale solution; they could be a practical, reliable water system for cities. For some, foggy days, with their soft, quiet atmosphere, are the perfect reason to curl up and read. But, in addition to a lazy Sunday mood-setter, fog could soon also become a deeply vital resource. According to a new study published in the journal Frontiers in Environmental Science, atmospheric water, which of course includes fog, has the potential to serve as an effective water source for crucial uses like irrigation, hydroponic farming, and, probably most important, human consumption. The study focuses on fog in Alto Hospicio—a city on the edge of the Chilean Atacama Desert, which just so happens to be the driest non-polar place on Earth. On average, the desert gets less than one millimeter of rainfall every year. City inhabitants depend on massive sub-surface storehouses of water called underground aquifers. According to the U.S. Geological Survey, aquifers occur when porous, water-bearing rock readily transmits water to wells and springs. Think of when you're at the beach and dig so deep in the sand that the hole gets flooded with water. You've just dug a well to expose the water table and aquifer underneath. While this may seem like a reliable water source, the aquifers at Alto Hospicio haven't been recharged in over 10,000 years. Researchers conducted the study over the course of a year and found that peak fog season fell between August and September in 2024. The fog-harvesting contraption researchers used is extremely simple, using a suspended piece of mesh to intercept the fog. Water droplets form on the fabric and eventually run down to a gutter into storage tanks. According to the researchers, the system is low-cost, passive, and low-maintenance. After the year-long study, researchers found the fog-harvesting system could produce a daily average of 2.5 liters of water per square meter. During peak season, the fog-harvester has the potential to collect 10 liters of water per square meter a day. Authors of the study suggest that 17,000 square meters of mesh could produce enough to meet the weekly water needs (300,000 liters) of communities that face similar struggles as Alto Hospicio. 'This research represents a notable shift in the perception of fog water use—from a rural, rather small-scale solution to a practical water resource for cities,' said Dr Virginia Carter Gamberini, first co-author of the study, in a Frontiers press release. 'Our findings demonstrate that fog can serve as a complementary urban water supply in drylands where climate change exacerbates water shortages.' According to the paper, confronting water scarcity could correct the social inequality that non-renewable water systems perpetuate. Water stress affects many regions—including Chile—especially because of urban growth and megadroughts. 'The collection and use of water,' Carter said, 'especially from non-conventional sources such as fog water, represents a key opportunity to improve the quality of life of inhabitants.' You Might Also Like The Do's and Don'ts of Using Painter's Tape The Best Portable BBQ Grills for Cooking Anywhere Can a Smart Watch Prolong Your Life?
Yahoo
20-02-2025
- Science
- Yahoo
In the driest place on Earth, water hides in plain sight
The Atacama Desert in northern Chile sits in the rain shadow of the Andes Mountains. Though it borders the Pacific Ocean, a persistent cold flow known as the Humboldt Current keeps moisture levels in the air relatively low. Clouds form, but quickly dissipate. As a result, rain comes rarely and in small amounts– a few millimeters per year, on average in some parts. In other parts, decades-old weather stations have never recorded any precipitation. Outside of a handful of valleys in Antarctica, the Atacama is the driest place on Earth. The inhospitable landscape of sand, bare rock, and salt flats is so extreme and otherworldly that it's used as a proxy for Mars by researchers. Yet still, people live there–mostly in a smattering of coastal cities and towns. Iquique, the oceanside regional capital, is home to more than 230,000 people. Just inland and upslope from Iquique is the fast-growing municipality of Alto Hospicio, which has ballooned to more than 140,000 people (up from fewer than 100,000 in 2012) amid a lithium mining boom. Fresh water comes from an underground aquifer, which hasn't been meaningfully refreshed by rainfall for nearly 10,000 years. As more people rely on the aquifer, it's drying up. Eventually, there will be nothing left. Desalination plants, which remove salt from ocean water, can fill some of the need, but they are expensive and energy intensive to run, especially for low-income cities like Alto Hospicio. Most desalination plants in the region service mining operations, not people. An alternative, as-of-yet untapped, and inexpensive water source could help resolve the burgeoning water crisis. And it's water that's been hiding in plain view. Fog harvesting is a sustainable, simple method for collecting moisture from low-lying clouds. It's long been used in rural areas around the world to support isolated villages of a few hundred people. But a new study suggests it could work on a much grander scale. An analysis published February 20 in the journal Frontiers in Environmental Science suggests fog harvesting could meet the needs of Alto Hospicio's informal settlements, providing as much as 300,000 liters per week to 10,300 people, who mostly live disconnected from the formal water distribution system. Currently, they rely on the disappearing aquifer, but that water is delivered to them via trucks instead of pipes, upping the cost and reducing reliability and accessibility. For inhabitants of these settlements, the water supply is even shakier than for the rest of the city's residents, and thus fog offers an even bigger opportunity. Beyond drinking water, fog harvesting could also be used to irrigate green spaces in the region, or to fuel hydroponic agriculture–offering people a cheap source of locally grown, fresh food. On its own, 'this water is not going to save the city,' says Virginia Carter, lead study author, a geographer, and an assistant professor at the Universidad Mayor in Chile. But fog is a resource that might make a real difference, she says. 'It could contribute, and in many places it might be important,' Carter explains, especially as Alto Hospicio continues to grow and climate change makes the existing water supply even more tenuous. Fog harvesting relies on a low-tech set-up. Usually, a fine plastic mesh, like the type that might be used to shade heat-sensitive garden beds, is strung across two support poles a few feet in the air. A gutter beneath the mesh channels the moisture that condenses on the panel into a storage container, so it can be readily collected. The more panels and greater surface area of mesh used, the more water is harvested. Unlike the aquifer beneath the Atacama, fog water is a potentially renewable resource. Low clouds routinely get churned up from the Pacific and blow overland. Without the mesh, the moisture evaporates in the dry air as the temperature rises each day, but with it, the fog would be only temporarily waylaid– providing valuable fresh water to people, before it's treated and cycled back into the ocean. To demonstrate that fog harvesting would be worthwhile for Alto Hospicio and northern Chile more broadly, Carter and her co-authors combined a year of observational measurements with satellite imagery and mathematical modeling of the region's fog cycles. The researchers set up two one-square-meter 'standard fog collectors' at different altitudes, along with a weather station to keep tabs on air moisture, temperature, wind speed, and other variables. They also used remote sensing to map fine-grained altitude and fog density across the province. Finally, they synthesized this and other data from existing fog collector projects into a mathematical model intended to estimate how much fog could be harvested at different times. They found that the fog is highly seasonal, appearing from May through October (the Southern Hemisphere's winter into spring). It peaks in June during the night and early morning, and all but disappears in the warmer months and by midday. In the zones immediately around Alto Hospicio, fog collectors would yield an estimated average of 2.5 liters of water per square meter of mesh during the fog season, according to the study. At this rate, it would take 17,000 square meters of collectors (just over three football fields' worth) to yield 300,000 liters a week–the same volume of water currently delivered via truck to Alto Hospicio's informal settlements each week. However, Carter notes this is a conservative estimate, as certain areas to the north of the city have much more fog potential than the average, producing more than 5 liters per meter of mesh per day. If fog collectors were placed strategically, then just 200-300 fog collectors (each encompassing about 20 square meters) could reliably provide hundreds of thousands of liters for at least half the year, she explains. Complementary storage tanks or ponds could stretch the fog water into a year-round resource. 'This is kind of a dream. To develop something like that for Alto Hospicio,' Carter says. If providing drinking water to 10,000+ people proves too big of an initial goal, smaller pilot projects might offer a proof of concept. Carter and her colleagues suggest fog harvesting could also be used to irrigate public parks or provide water to hydroponic farms, with less initial investment. Just 110 square meters of mesh would be needed to fulfill the city's green space needs. One square meter of fog collection could yield more than 15 kg of leafy greens each year. Before the dream becomes a reality though, further work is needed. The scientists would like to verify their model estimates with more on-the-ground measurements, to home in on the best locations for fog collectors. Carter says she also hopes to test the quality of the harvested water, and determine what type of treatment would be needed to make it safe for human consumption. Fog can carry exhaust particles, bacteria, and microplastics–like any other natural water source. Yet, even untreated, the water could still have applications in agriculture or mining. And already the research is advancing. Carter and her colleagues plan to release a publicly accessible, detailed map of fog for all of northern Chile later this year, based on their model. She hopes that local and national government officials take notice. 'This study is a very clear example of how scientific knowledge [can] contribute to public decision-making and policies,' she says. 'We have a problem: We have no water, and it's getting worse. But on the other hand, there's a solution. There's this water sitting and waiting. We just need a logical way to harvest it.'
