Low-cost device can measure air pollution anywhere

MIT researchers have made an open-source version of the “City Scanner” mobile pollution detector that lets people check air quality anywhere, cheaply. Pictured are some examples of the latest version of the device, called Flatburn, as well as a researcher attaching a prototype to a car.
Image Credits: Courtesy of the researchers. Edited by MIT News
(CC BY-NC-ND 3.0)

Air pollution is a major public health problem: The World Health Organization has estimated that it leads to over 4 million premature deaths worldwide annually. Still, it is not always extensively measured. But now an MIT research team is rolling out an open-source version of a low-cost, mobile pollution detector that could enable people to track air quality more widely.

The detector, called Flatburn, can be made by 3D printing or by ordering inexpensive parts. The researchers have now tested and calibrated it in relation to existing state-of-the-art machines, and are publicly releasing all the information about it — how to build it, use it, and interpret the data.

“The goal is for community groups or individual citizens anywhere to be able to measure local air pollution, identify its sources, and, ideally, create feedback loops with officials and stakeholders to create cleaner conditions,” says Carlo Ratti, director of MIT’s Senseable City Lab. 

“We’ve been doing several pilots around the world, and we have refined a set of prototypes, with hardware, software, and protocols, to make sure the data we collect are robust from an environmental science point of view,” says Simone Mora, a research scientist at Senseable City Lab and co-author of a newly published paper detailing the scanner’s testing process. The Flatburn device is part of a larger project, known as City Scanner, using mobile devices to better understand urban life.

Humans are altering the diet of Tasmanian devils, which may accelerate their decline

The researchers investigated the diets of devils from habitats of differing levels of disturbance.
Photo Credit: Ariana Ananda.

New research shows how human-modified landscapes affect the diets of these marsupial scavengers.

The Tasmanian devil roams the island state of Australia as the apex predator of the land, feeding on whatever it pleases as the top dog – or the top devil. But some of these marsupial scavengers could be starting to miss out on a few items from the menu.

According to a study led by UNSW Sydney, living in human-modified landscapes could be narrowing the diet of the Tasmanian devil. The research, published recently in Scientific Reports, suggests devils have access to vastly different cuisines depending on the type of environment they live in.

“We found Tasmanian devil populations had different levels of variation in their diet depending on their habitat,” says Anna Lewis, a PhD candidate at UNSW Science and lead author of the study. “The more that habitat was impacted by humans, the more restrictive the diet became.”

A previous study by the team found most devils are individual specialists, feeding on the same food items consistently over time. But human impacts could be influencing whether they have access to their favorite foods.

“How humans change the environment impacts the animals within them,” says Professor Tracey Rogers, an ecologist at UNSW Science and senior author of the study. “Even small changes can have significant consequences for devils, so we need to be mindful of the consequences of our actions.”

Dry forests and savannas vital for Brazil’s climate goals

Cerrado savanna
Photo Credit Tim Hill

Brazil must protect and restore its dry forests and savannas to achieve its climate goals, new research shows.

Attention in Brazil and worldwide often focusses on the Amazon rainforest – ignoring damage and destruction of these seasonally dry biomes, which contain vast biodiversity and carbon stores.

The new study, led by the universities of Exeter and Campinas, says cost-effective restoration of savannas and dry forests could lock in 1.5 billion tons of carbon in 100 years.

But restoration takes time, and the researchers say protecting existing ecosystems is the best option for Brazil to reach its 2030 climate goals.

“Ongoing land-use change – especially the destruction of ecosystems to create agricultural land – makes Brazil the world’s fifth-biggest greenhouse gas emitting country,” said Dr Lucy Rowland, from Global Systems Institute at the University of Exeter.

Game-changing high-performance semiconductor material could help slash heat emissions

WVU researchers Sergio Andres Paredes Navia, Cesar Octavio Romo de la Cruz, Liang Liang and Ellena Gemmen use an electron microscope to study the nanostructure of a new oxide ceramic material with the potential to make thermoelectric generators efficient enough to capture a significant portion of the waste heat that industrial systems like power plants emit.
Photo Credit: Courtesy of West Virginia University

Researchers at West Virginia University have engineered a material with the potential to dramatically cut the amount of heat power plants release into the atmosphere.

A team led by Xueyan Song, professor and George B. Berry Chair of Engineering at the Benjamin M. Statler College of Engineering and Mineral Resources, has created an oxide ceramic material that solves a longstanding efficiency problem plaguing thermoelectric generators. Those devices can generate electricity from heat, including power plant heat emissions, which contribute to global warming.

The breakthrough oxide ceramic Song’s team produced “achieved a record-high performance that had been deemed impossible,” she said. “We demonstrated the best thermoelectric oxide ceramics reported in the field worldwide over the past 20 years, and the results open up new research directions that could further increase performance.”

Oxide ceramics are from the same family as materials like pottery, porcelain, clay bricks, cement and silicon, but contain various metallic elements. They’re hard, resistant to heat and corrosion, and well-suited for high-temperature applications in air. They can serve as the material for thermoelectric generator components.

Cow dung possible sustainable material of the future, study finds

Photo Credit: Jonas Koel

Livestock dung could be used to create the next generation of cellulosic materials, according to a new report.

Livestock dung is typically used as a fertilizer or as a source of biogas for green energy applications, but the study, led by scientists at Scotland’s Rural College (SRUC) in collaboration with the universities of Bristol and Edinburgh, reviewed recent research into the development of high-value manure-derived materials from ruminant animals such as cattle.

They found that dung has been largely overlooked despite the variety of different applications for recycled ruminant waste biomass (RWB).

The most common applications use manure in combination with other components to create composite materials such as plastic, recycled card and paper or concrete. However, it could also be used for the extraction of nanocellulose - a prospective bio-based and biodegradable material of the future.

Currently, there is a trade-off between the performance of the material and the amount of processing required to achieve this – limiting the capacity of RWB to replace conventional materials on a commercial level.

Invasive Grass in Texas Uses Chemical Warfare to Crowd Out Native Species

Photo Credit: Courtesy of University of Texas at Austin

An invasive grass causing havoc in Texas and contributing to wildfires packs a one-two wallop against native plants. Guinea grass uses a combination of crowding that blocks out light from growing seedlings and what amounts to a chemical warfare in soil that is toxic to native plants, according to a new study by researchers at The University of Texas at Austin.

The findings are published in the journal Ecosphere.

Guinea grass is one of the most ecologically damaging invasive species in the world, arriving in South Texas from Africa more than 100 years ago, to help feed cattle. In the past 20 years, it has spread aggressively across the region and can now be found along roadsides as far north as Austin, bringing with it the risk of more frequent, high-intensity wildfires.

The researchers said knowing about how an invasive species takes over an area is an important step in figuring out how to control and reduce it in the environment.

“The shading and the chemical toxins are each effective at pushing out native plants on their own, but combined, the negative effects increased dramatically,” said Colin Morrison, a graduate student in the Department of Integrative Biology who is the lead author on the paper.

Berkeley researchers present plan for freshwater conservation

Study authors say freshwater conservation priorities should include connectivity, watershed disturbance, flow alteration, water quality, and biodiversity.
(A) Briones Dam reduces connectivity in Bear Creek, California.
(B) Wildfire in Hopland, California, creates widespread watershed disturbance.
(C) poor water quality in Porter Creek, California, kills fish and reduces recreational opportunities.
(D) freshwater ecosystems support biodiversity in Klamath Lake, Oregon.
Photo Credits: (A) L Andrews, (B) P Parker Shames, (C) G Rossi, (D) J Shames

The 30x30 initiative is a global effort to set aside 30% of land and sea area for conservation by 2030, a move scientists hope will reverse biodiversity loss and mitigate the effects of climate change. Now adopted by state and national governments around the world, 30x30 creates an unprecedented opportunity to advance global conservation.

When it comes to the water side of 30x30, most programs focus primarily on conservation of oceans, but a new study by researchers at the University of California, Berkeley argues that freshwater ecosystems must not be neglected. Published today in the journal Frontiers in Ecology and the Environment, the paper urges policy makers to explicitly include freshwater ecosystems like rivers, lakes, and wetlands in 30x30 plans, and outlines how their conservation will be critical to achieving the initiative’s broader goals. 

Stress memory in plants could hold key to growing disease resistant crops

Scientists at the University of Sheffield have discovered a mechanism behind how plants can acquire long-lasting resistance against attacks from insects
Illustration Credit: Courtesy of The University of Sheffield

A mechanism behind how plants can develop long-term immunity to stress has been discovered by scientists at the University of Sheffield.

Biotic stress experienced by plants can take the form of attacks by insect herbivores or disease-causing pathogens. In crops grown for food production, this stress provides a substantial risk to crop yields and is currently managed with the widespread use of pesticides, which are damaging for the environment and can pose a risk to human health.

Due to the urgent need to find better and more sustainable plant protection methods, Professor Jurriaan Ton, from the University of Sheffield’s Institute for Sustainable Food, and his team, investigated how plants are able to acquire long-lasting immunity against these stressors.

The findings, published in Nature Plants, explain a mechanism of how plants ‘remember’ the stress from a previous attack, and that this long-term memory is encoded in a family of 'junk DNA’ that can prime defense genes for several weeks against further attacks.

Does current shellfish culture gear curb ‘crunching’ rays?

Whitespotted eagle rays “crunching” on clams in a large outdoor tank with clams housed within a variety of anti-predator materials.

Video Credit: Florida Atlantic University / Harbor Branch Oceanographic Institute 

According to NOAA Fisheries, more than 80 percent of marine aquaculture production in the United States consists of bivalve mollusks such as oysters, clams and mussels. However, it’s not just humans who enjoy eating these shellfish, so do marine rays. They like to “crunch” on clams, which can sometimes take a big bite out of clammers’ profits.

Part of the process of culturing hard clams (Mercenaria mercenaria) involves deploying them in submerged bottom leases in the marine environment where clams can grow to market size. When deployed onto the clam lease, clammers incorporate a variety of anti-predator materials to protect their product, such as woven mesh netting and/or additional mesh, plastic or wire covers.

However, the effectiveness of these materials against highly mobile predators like rays has not been experimentally tested. Some rays, like the whitespotted eagle ray (Aetobatus narinari), are equipped with strong jaws, plate-like teeth and nimble pectoral fins, which make them formidable and highly maneuverable predators of clams.

Plastic containers can contain PFAS — and it’s getting into food

Illustration Credit: University of Notre Dame

Researchers at the University of Notre Dame are adding to their list of consumer products that contain PFAS (per- and polyfluoroalkyl substances), a toxic class of fluorine compounds known as “forever chemicals.”

In a new study published in Environmental Science and Technology Letters, fluorinated high-density polyethylene (HDPE) plastic containers — used for household cleaners, pesticides, personal care products and, potentially, food packaging — tested positive for PFAS. Following a report conducted by the EPA that demonstrated this type of container contributed high levels of PFAS to a pesticide, this research demonstrates the first measurement of the ability of PFAS to leach from the containers into food as well as the effect of temperature on the leaching process.

Results also showed the PFAS were capable of migrating from the fluorinated containers into food, resulting in a direct route of significant exposure to the hazardous chemicals, which have been linked to several health issues including prostate, kidney and testicular cancers, low birth weight, immunotoxicity and thyroid disease.

“Not only did we measure significant concentrations of PFAS in these containers, we can estimate the PFAS that were leaching off creating a direct path of exposure,” said Graham Peaslee, professor of physics in the Department of Physics and Astronomy at Notre Dame and an author of the study.

Pioneering study shows flood risks can still be considerably reduced if all global promises to cut carbon emissions are kept

Maps show historical expected annual flood damage (EAD) in GBP billion at 2020 values, and calculated EAD percentage increase with 1.8 degrees global warming.
Illustration Credit: University of Bristol and Fathom

Annual damage caused by flooding in the UK could increase by more than a fifth over the next century due to climate change unless all international pledges to reduce carbon emissions are met, according to new research.

The study, led by the University of Bristol and global water risk modelling leader Fathom, reveals the first-ever dataset to assess flood hazard using the most recent Met Office climate projections which factor in the likely impact of climate change.

Its findings show the forecasted annual increase in national direct flood losses, defined as physical damage to property and businesses, due to climate change in the UK can be kept below 5% above recent historical levels. But this is only on the proviso that all countries fulfil the ambitious pledges they signed up to at COP26 and also that countries, including the UK, which made further Net Zero commitments, actually achieve these on time and in full.

New Fluorescent Sensors Make it Possible to Detect the Concentration of Mercury in Water

New fluorophores selectively and with high sensitivity recognize mercury ions.
Photo Credit: Anna Marinovich

Scientists from the UrFU, together with Italian and Bulgarian colleagues, synthesized new heterocyclic fluorophores - four types of carboxamides of 2-aryl-1,2,3-triazoles. Their photophysical properties have been investigated under different conditions - solvents and their binary mixtures with water. Sensors based on the fluorophores obtained were sensitive to mercury, so they can be used to detect mercury concentrations in water. Further research will focus on determining the possibility of using these fluorophores to target medicines to affected organs. The authors have published an article on their research and results in the journal Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy.

"A disadvantage of organic fluorophores is their poor solubility in water and aqueous environments. At the same time, when water is added to organic solvents, most dyes and fluorophores have fluorescence quenching. However, in 2001, Professor Ben Zhong Tan of the Chinese University of Hong Kong found that some fluorophores observed not quenching, but rather an increase the fluorescence intensity. This is due to the formation of much larger particles, or nano-aggregates, from the molecules of fluorophores. Tan's discovery was of great significance. Much scientific effort has been devoted to studying the mechanism of his discovery, as well as to the design and synthesis of new fluorophores with the effect of increasing the emission. The fluorophores we obtained have also demonstrated in a mixture of organic solvent and water the effect described by Tang, and with a particular intensity. This opens the way to the practical application of the obtained fluorophores in various fields, especially in the aquatic environment," says Natalya Belskaya, Full Professor of the UrFU Department of Technology of Organic Synthesis and leader of the research team.

Water quality expert develops public tool for diagnosing health of America’s streams

WVU master's degree students Samira Jahan and Md. Tanvirul Islam discuss water quality data with Omar Abdul-Aziz, associate professor in the WVU Benjamin M. Statler College of Engineering and Mineral Resources. Abdul-Aziz has publicly released a model for diagnosing the health of any U.S. freshwater stream in the past, present or future using only water temperature.
Photo Credit: Matt Sunday / West Virginia University

A model for predicting the levels of oxygen in water, developed by West Virginia University researcher Omar Abdul-Aziz, gives citizen scientists nationwide a tool for taking action on stream pollution. 

“I have been looking at water quality data for 20 years,” said Abdul-Aziz, an associate professor at the Benjamin M. Statler College of Engineering and Mineral Resources. “I can tell you that a big percentage of streams in the United States are polluted. Urban streams are getting dumpster runoff, stormwater carrying lawn fertilizers and trash. Wastewater plants aren’t necessarily treating for the dissolved organic carbon, nutrients and pharmaceuticals we’re putting into our sewage.

Abdul-Aziz’s model relies on only water temperature and pH, a measure of acidity, to give an accurate measure of the health of any freshwater stream in the contiguous United States as represented by the amount of oxygen dissolved in the water. Oxygen is fundamental to stream health, and his model is significant because it predicts how much oxygen is in the water of any given stream at any location or time, based on a small amount of easily obtainable data.

Climate change raises the threat of multiple hurricanes

Princeton researchers explored the increasing risk of multiple destructive storms hitting locations on the Atlantic and Gulf coasts. In this image, three storms formed in the Atlantic basin in 2017. 
Photo Credit: NASA

Getting hit with one hurricane is bad enough, but new research from Princeton Engineering shows that back-to-back versions may become common for many areas in coming decades.

Driven by a combination of rising sea levels and climate change, destructive hurricanes and tropical storms could become far more likely to hit coastal areas in quick succession, researchers found. In an article published Feb. 27 in the journal Nature Climate Change, the researchers said that in some areas, like the Gulf Coast, such double hits could occur as frequently as once every three years.

“Rising sea levels and climate change make sequential damaging hurricanes more likely as the century progresses,” said Dazhi Xi, a postdoctoral researcher and a former graduate student in civil and environmental engineering and the paper’s lead author. “Today’s extremely rare events will become far more frequent.”

Blue whale foraging and reproduction are related to environmental conditions, study shows

A blue whale surfaces
Photo Credit: Three-shots

A new study of New Zealand blue whales’ vocalizations indicates the whales are present year-round in the South Taranaki Bight and their behavior is influenced by environmental conditions in the region.

The findings are a significant advancement in researchers’ understanding of the habitat use and behavior of this population of blue whales, which Oregon State University researchers first identified as genetically distinct from other blue whale populations less than a decade ago.  

“We went from not knowing 10 years ago whether this was a distinct population to now understanding these whales’ ecology and their response to changing environmental conditions,” said the study’s lead author, Dawn Barlow, a postdoctoral scholar in OSU’s Marine Mammal Institute. “These findings can inform conservation management of this blue whale population and their habitat.”

The patterns and intensity of the whales’ calls and songs over two years showed strong seasonality in their foraging and breeding behavior, and the vocalizations changed based on environmental conditions such as a documented marine heatwave, Barlow said.

“During the marine heatwave, feeding-related calls were reduced, reflecting poor foraging conditions during that period,” Barlow said. “But we also saw changes in vocalizations in the next breeding period, an indication that they put less effort into reproduction following a period of poor feeding conditions.”

Zombie forests

As the climate changes, plants often struggle to keep up. In many areas, the vegetation that stands today may not be well adapted for the climate it is now living in. After a major disturbance, such as a wildfire, the plant community likely will not return.

Video Credit: Lindsay Filgas, Madison Pobis & Rob Jordan

The researchers created maps showing where warmer weather has left trees in conditions that don’t suit them, making them more prone to being replaced by other species. The findings could help inform long-term wildfire and ecosystem management in these “zombie forests.”

Like an old man suddenly aware the world has moved on without him, the conifer tree native to lower elevations of California’s Sierra Nevada mountain range finds itself in an unrecognizable climate. A new Stanford-led study reveals that about a fifth of all Sierra Nevada conifer forests – emblems of Western wilderness – are a “mismatch” for their regions’ warming weather. The paper, published Feb. 28 in PNAS Nexus, highlights how such “zombie forests” are temporarily cheating death, likely to be replaced with tree species better adapted to the climate after one of California’s increasingly frequent catastrophic wildfires.

“Forest and fire managers need to know where their limited resources can have the most impact,” said study lead author Avery Hill, a graduate student in biology at Stanford’s School of Humanities & Sciences at the time of the research. “This study provides a strong foundation for understanding where forest transitions are likely to occur, and how that will affect future ecosystem processes like wildfire regimes.” Hill led a related study this past November showing how wildfires have accelerated the shifting of Western trees’ ranges.

In the end, it's the individual advantage that counts

The three phases of exceptional dynamics: (1) Predation on the unprotected bacteria by predators, (2) toxin formation as cooperative defense and recovery of the bacterial population, (3) filament formation as individual defense through evolution and stabilization of densities.
Photo Credit: David Kneis/TU Dresden

Bacteria rely on cooperation and evolution in order to defend themselves against predatory protists

Eating and being eaten is a normal process in nature. These predator-prey dynamics help to stabilize ecosystems. It ensures that individual species do not become too abundant, controls their populations, and prevents damage caused by overpopulation (e.g., browsing by deer in the forest or damage to crops by caterpillars). But how is it that the predators do not simply eat away all the prey, thus breaking down the system? A research team from the Helmholtz Centre for Environmental Research (UFZ) together with scientists from the Technical University (TU) of Dresden and the University of Potsdam has investigated this using bacteria and protists that live in bodies of water and discovered something astonishing. According to an article recently published in ISME Journal, bacteria defend themselves against predatory protists with cooperative behavior and evolution.

In a lake or river, between one and 10 million bacteria live in just 1 ml of water. Such a high density is necessary because bacteria permanently break down organic compounds and pollutants and thus purify the water. However, if there are too many bacteria, this can lead to the spread of pathogens. Preventing this requires predators: microscopic protists of which there are usually between a few hundred and a few thousand individuals in 1 ml of water. They constantly eat bacteria and thus ensure that the bacteria fulfil their cleaning function but do not become too abundant. Using the bacterium Pseudomonas putida and the bacterivorous protist Poteriospumella lacustris, the research team investigated the role of the various defense strategies of the bacteria and how the formation of feeding resistance is related to the dynamics of ecological systems.

Breathing is going to get tougher

Dust rising at Noordoewer, Namibia. Research shows dust will be a major contributor to poor air quality as the climate changes.
Photo Credit: Matthieu Joannon

Not all pollution comes from people. When global temperatures increase by 4 degrees Celsius, harmful plant emissions and dust will also increase by as much as 14 percent, according to new UC Riverside research.

The research does not account for a simultaneous increase in human-made sources of air pollution, which has already been predicted by other studies. 

“We are not looking at human emissions of air pollution, because we can change what we emit,” said James Gomez, UCR doctoral student and lead author of the study. “We can switch to electric cars. But that may not change air pollution from plants or dust.”

Details of the degradation in future air quality from these natural sources have now been published in the journal Communications Earth & Environment. About two-thirds of the future pollution is predicted to come from plants.

All plants produce chemicals called biogenic volatile organic compounds, or BVOCs. “The smell of a just-mowed lawn, or the sweetness of a ripe strawberry, those are BVOCs. Plants are constantly emitting them,” Gomez said.

Researchers find sea urchin die-offs threaten Caribbean coral reefs

The urchin species Diadema antillarum has long been considered the most important grazer in the Caribbean, feeding on algae that would otherwise overrun the reef and make it difficult for coral to thrive.
Photo Credit: Rachel Best

The sustained loss of a once abundant species of sea urchin in the Caribbean could also result in the functional extinction of diverse coral species from the region’s reefs, according to new research from a Florida State University team.

The urchin species Diadema antillarum has long been considered the most important grazer in the Caribbean, feeding on algae that would otherwise overrun the reef and make it difficult for coral to thrive. But two mortality events over the past 40 years have caused much of that urchin population to die off.

New research led by FSU Professor of Biological Science Don Levitan shows that the loss of these algae-free areas due to the sea urchin die-off is threatening the existence of the corals that populate Caribbean reefs.

Levitan, along with collaborator Peter Edmunds, a professor at California State University Northridge, has been collecting data on D. antillarum since his first research trip to St. John, U.S. Virgin Islands, in 1983, recording population density of the species and tracking it through mass mortality events in 1983-1984 and in 2022.

Voluntary UK initiatives to phase out toxic lead shot for pheasant hunting have had little impact

Pheasant
Photo Credit: Julie Mayo

The pledge, made in 2020 by nine major UK game shooting and rural organizations, aims to protect the natural environment and ensure a safer supply of game meat for consumers. Lead is toxic even in very small concentrations, and discarded shot from hunting poisons and kills tens of thousands of the UK’s wild birds each year.

A Cambridge-led team of 17 volunteers bought whole pheasants from butchers, game dealers and supermarkets across the UK in 2022-23. They dissected the birds at home and recovered embedded shotgun pellets from 235 of the 356 pheasant carcasses.

The main metal present in each shotgun pellet was revealed through laboratory analysis - conducted at the Environmental Research Institute, University of the Highlands and Islands, UK. Lead was the main element in 94% of the recovered shot pellets; the remaining 6% were predominantly composed of steel or a metal called bismuth.