University of Greenwich

A one-month indoor gardening period increased the bacterial diversity of the skin and was associated with higher levels of anti-inflammatory molecules in the blood. A one-month indoor gardening period increased the bacterial diversity of the skin and was associated with higher levels of anti-inflammatory molecules in the blood demonstrated a collaborative study between the University of Helsinki, Natural Resources Institute Finland and Tampere University. In his doctoral thesis, Mika Saarenpää investigated, among other things, how microbial exposure that promotes the health of urban residents, particularly enhancing their immune regulation, could be increased easily through meaningful activities integrated into everyday life. Previously, it has been shown that contact with nature-derived, microbially rich materials alters the human microbiota. In Saarenpää's study, research subjects committed to urban gardening, a natural activity for them, which may result in long-term changes in the functioning of the immune system. "One month of urban indoor gardening boosted the diversity of bacteria on the skin of the subjects and was associated with higher levels of anti-inflammatory cytokines in the blood. The group studied used a growing medium with high microbial diversity emulating the forest soil," says Doctoral Researcher Mika Saarenpää from the Faculty of Biological and Environmental Sciences, University of Helsinki. In contrast, the control group used a microbially poor peat-based medium. According to Saarenpää, no changes in the blood or the skin microbiota were seen. Peat is the most widely used growing medium in the world, and the environmental impact of its production is strongly negative. Moreover, Saarenpää's research indicates that it does not bring health benefits similar to a medium mimicking diverse forest soil. "The findings are significant, as urbanisation has led to a considerable increase in immune-mediated diseases, such as allergies, asthma and autoimmune diseases, generating high healthcare costs. We live too 'cleanly' in cities," Saarenpää says. "We know that urbanisation leads to reduction of microbial exposure, changes in the human microbiota and an increase in the risk of immune-mediated diseases. This is the first time we can demonstrate that meaningful and natural human activity can increase the diversity of the microbiota of healthy adults and, at the same time, contribute to the regulation of the immune system." Urban gardening is an effortless way to improve health Microbial exposure can be increased easily and safely at home throughout the year. The space and financial investment required is minor: in the study, the gardening took place in regular flower boxes, while the plants cultivated, such as peas, beans, mustards and salads, came from the shop shelf. Changes were observed already in a month, but as the research subjects enjoyed the gardening, many of them announced that they would continue the activity and switch to outdoor gardening in the summer. According to Saarenpää, microbe-mediated immunoregulation can, at its best, reduce the risk of immune-mediated diseases or even their symptoms. If health-promoting microbial exposure could be increased at the population level, the healthcare costs associated with these diseases could be reduced and people's quality of life improved. "We don't yet know how long the changes observed in the skin microbiota and anti-inflammatory cytokines persist, but if gardening turns into a hobby, it can be assumed that the regulation of the immune system becomes increasingly continuous," Saarenpää notes. Saarenpää considers it important to invest in children's exposure to nature and microbes, as the development of the immune system is at its most active in childhood. Planter boxes filled with microbially rich soil could be introduced at kindergartens, schools and, for example, hospitals, especially in densely built urban areas. For urban gardening to bring health benefits instead of risks, the skin of the hands in particular must be unbroken, and the inhalation of dusty growing media avoided. "My research emphasises the dependence of our health on the diversity of nature and that of soil in particular. We are one species among others, and our health depends on the range of other species. Ideally, urban areas would also have such a diverse natural environment that microbial exposure beneficial to health would not have to be sought from specifically designed products," Saarenpää sums up.

A research group was able to measure a spike in radiocarbon concentration of trees in Lapland that occurred after the Carrington flare. This discovery helps to prepare for dangerous solar storms. A research group coordinated by the University of Helsinki was able to measure a spike in radiocarbon concentration of trees in Lapland that occurred after the Carrington flare. This discovery helps to prepare for dangerous solar storms. The Carrington Event of 1859 is one of the largest recorded solar storms in the last two centuries. It was seen as white light flares on a giant sunspot group, fires at telegraph stations and disturbances in geomagnetic measurements, as well as aurorae even in tropical regions. In a joint study carried out by the University of Helsinki, Natural Resources Institute Finland and the University of Oulu, a sign of an increase in radiocarbon concentrations following the Carrington storm was detected for the first time in tree rings. Previously, radiocarbon traces have only been detected from far more intense solar storms. Discovery through a cosmic marker Encounters between strong magnetised clouds of charged particles released from the Sun, known as solar plasma flows, and Earth's geomagnetic field result in geomagnetic storms. The geomagnetic field directs the solar storm particles into the atmosphere primarily through the Polar regions. The most visible consequence of the phenomenon are aurorae. In the upper atmosphere, sufficiently high-energy particles can, through nuclear reactions, also produce radiocarbon (14C), a radioactive isotope of carbon. Over the course of months and years, radiocarbon ends up in the lower atmosphere as part of atmospheric carbon dioxide, and eventually in plants through photosynthesis. The process of photosynthesis preserves the information contained in carbon dioxide in the annual rings of trees. To obtain the information held by radiocarbon, samples are extracted by carving from the wood material grown over individual years. The samples are processed to cellulose and the cellulose into pure carbon by burning and chemical reduction. The fraction of radiocarbon in pure carbon is measured using a particle accelerator. "Radiocarbon is like a cosmic marker describing phenomena associated with Earth, the solar system and outer space," says Markku Oinonen, Director of the University of Helsinki's Laboratory of Chronology, who headed the study. Mapping solar storms A solar storms corresponding to the Carrington event in modern times would disrupt electrical and mobile networks and cause major problems for satellite and navigation systems, leading to problems in, for example, air traffic. This is why accurate knowledge of solar behaviour benefits society. Solar storms smaller and more common than the Carrington storms can be studied with measuring devices and satellites nowadays, while larger ones can be investigated, for example, by measuring radiocarbon concentration in tree rings. So far, it has not been possible to study specifically medium-sized storms such as the Carrington event, which have not occurred in modern times, using conventional radiocarbon techniques. This recent study opens up a potential new way of investigating the frequency of Carrington-sized storms, which may help to better prepare for future threats. Increasingly accurate information on the carbon cycle The results were interpreted using a numerical model of radiocarbon production and transport developed by researchers at the University of Oulu. "The dynamic atmospheric carbon transport model was specifically developed for describing geographical differences in the distribution of radiocarbon in the atmosphere," says Postdoctoral Researcher Kseniia Golubenko from the University of Oulu. What was significant in the recently published study was how the radiocarbon content of trees in Lapland differed from that of trees at lower latitudes. The first measurements were carried out at the Accelerator Laboratory of the University of Helsinki, while repeat measurements conducted in two other laboratories significantly reduced the previous uncertainties. The discovery can help to better understand atmospheric dynamics and the carbon cycle from the time before human-generated fossil fuel emissions, enabling the development of increasingly detailed carbon cycle models. "It's possible that the excess of radiocarbon caused by the solar flare was primarily transported to the lower atmosphere through northern regions, contrary to the general understanding of its movement," muses Doctoral Researcher Joonas Uusitalo from the Laboratory of Chronology. Other sources of radiocarbon "It's also possible that the cyclic change in the production of radiocarbon in the upper atmosphere caused by the variation in solar activity has resulted in the local differences on the ground level seen in our findings," Uusitalo adds. According to Uusitalo, the dominant fraction of radiocarbon is produced by galactic cosmic rays coming from outside the solar system, even though exceptionally strong solar storms generate individual bursts of the isotope in the atmosphere. Cosmic rays, in turn, are weakened by solar wind, a continuous flux of particles originating in the Sun that fluctuates between stronger and weaker in 11-year cycles. The topic requires further research. Historical records show that significant geomagnetic storms also took place in 1730 and 1770, which is why their tracking is likely to be in focus next. The recently published study was carried out as a collaborative project of the University of Helsinki's Laboratory of Chronology and Department of Physics, and Natural Resources Institute Finland. Researchers from the University of Oulu, Nagoya University, Yamagata University and ETH Zurich also contributed to the study. The study received funding from the Research Council of Finland, the Finnish Cultural Foundation and the Emil Aaltonen Foundation.

As climate change warms the Earth, higher-latitude regions will be at greater risk for toxins produced by algal blooms, according to new research. The findings identify water temperatures of 20 to 25 degrees Celsius (68 to 77 degrees Fahrenheit) as being at the greatest risk for developing dangerous levels of a common algae-produced toxin called microcystin. As climate change warms the Earth, higher-latitude regions will be at greater risk for toxins produced by algal blooms, according to new research led by Carnegie's Anna Michalak, Julian Merder, and Gang Zhao. Their findings, published in Nature Water, identify water temperatures of 20 to 25 degrees Celsius (68 to 77 degrees Fahrenheit) as being at the greatest risk for developing dangerous levels of a common algae-produced toxin called microcystin. Harmful algal blooms result when bodies of water get overloaded with nitrogen and phosphorus runoff from agriculture and other human activities. These excess nutrients can allow blue-green algae populations to grow at an out-of-control rate. Some blue-green algal species produce a toxin called microcystin, which can pose a serious health hazard to people and the environment, as well as pose economic risks for fishing and tourism. Microcystin affects liver function and can cause death in wild and domestic animals, including humans in rare instances. It is also classified as a potential carcinogen in cases of chronic exposure. "In 2014 an algal bloom in Lake Erie led to high levels of microcystin in water intakes, and residents in Ohio and Ontario were instructed not to drink tap water due to risk of exposure," Merder cautioned. Merder, Michalak, and their colleagues -- Carnegie's Gang Zhao, University of Kansas's Ted Harris, and Dimitrios Stasinopoulos and Robert Rigby of the University of Greenwich -- analyzed samples taken from 2,804 U.S. lakes between 2007 and 2017. They assessed how water temperature affects the occurrence and concentration of microcystin as part of an effort to better understand the risks to water quality posed by climate change. Michalak's lab has taken a leading role in understanding the intersection of climate change and water quality impairments for more than a decade. Previous work has shown that lakes worldwide are already experiencing more severe algal blooms and that nutrient pollution is being exacerbated by changes in rainfall patterns. "Lakes are sentinels of climate change," Michalak said. "They hold the vast majority, 87 percent, of the liquid freshwater on the Earth's surface, and the warming and precipitation shifts associated with climate change pose some of the greatest threats to water quality around the world and to the health of aquatic ecosystems." The surface temperatures of lakes have already been warming at 0.34 degrees Celsius (0.61 degrees Fahrenheit) per decade and Merder and Michalak set out to determine what this, as well as future warming, would mean in terms of risk for elevated toxin concentrations. "The abundance of blue-green algae is predicted to increase due to climate change as they outcompete other species," Merder explained. "But previous field studies came to various conclusions about what this means for microcystin concentrations." To inform land and water management strategies, it was important to quantitatively tie toxin levels to water temperature, which Merder and Michalak were able to accomplish through their extensive analysis of lake water samples, revealing that water temperatures in the 20 to 25 degrees Celsius (68 to 77 degrees Fahrenheit) range were most dangerous in terms of elevated microcystin concentrations. They also found that the impact of temperature is amplified when nutrient concentrations are high. By incorporating information from climate models, they were able to demonstrate that areas most susceptible to high toxin concentrations will continue to move northward. In some areas, the relative risk of exceeding water quality guidelines will increase by up to 50 percent in the coming decades. Additionally, they showed that toxin hazards will decrease in a small number of regions further south, as water temperatures begin to exceed those associated with the highest risk. "These findings should help demonstrate the serious risk to safe water for drinking, fishing, recreation, and other societal needs in many parts of the United States and the urgency for developing management strategies to prepare," Michalak concluded. "When we think about water sustainability in the context of global change, we need to focus on the quality of the water as much as we focus on the amount of water."