stress

Sea Urchins And Climate Change | Earth Wise

August 1, 2022 By EarthWise Leave a Comment

There is a thriving population of black sea urchins in bubbling volcanic vents off the coast of Ishia, a small island in the Gulf of Naples. The oceanic environment there is very acidic, high in carbon dioxide, and very warm. The environment represents a proxy for what is gradually happening to oceans around the world.

Researchers from the University of Sydney have determined that the ability of sea urchins to prosper in such an environment means that these animals, which are already abundant in the Mediterranean Sea are likely to spread further afield as oceans continue to warm and become more acidic. The Mediterranean Sea is warming 20% faster than the global average.

Sea urchins are already an environmental problem in many places around the world. When their numbers increase disproportionately, they decimate kelp forests and algae, leading to the demise of other species that depend on these things for food or shelter. The result is something called an urchin barren, which is a rocky, sandy, urchin-filled seafloor devoid of other life.

Urchin barrens are increasingly common in many places, including the east coast of Australia and the coastline in the Americas stretching from Nova Scotia to Chile.

In Australia, for example, sea urchin populations have multiplied, and their range has expanded considerably, overgrazing kelp and damaging abalone and lobster farms.

Tests run by the Sydney researchers found that it is difficult to stress sea urchins. They appear to tolerate conditions that other creatures simply cannot. The only real positive is that understanding the urchins’ remarkable survival abilities might offer insights into adaptations that other animals might need in order to survive as the oceans become warmer and more acidic.

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Colonising sea urchins can withstand hot, acidic seas

Photo, posted January 31, 2010, courtesy of Anna Barnett via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Resilient Microalgae | Earth Wise

July 21, 2022 By EarthWise Leave a Comment

The plight of the world’s coral reefs has been a growing environmental crisis for many years. Coral reefs provide sustenance and income to half a billion people, are major tourist attractions, protect coastlines, and are important centers of biodiversity. And because of the warming climate as well as other effects of human activity, more than half of the world’s coral reefs are under stress.

The primary threat is coral bleaching, which is the disruption of the symbiotic relationship between coral polyps (which are tiny animals) and the heavily pigmented microalgae that live within the coral structures and provide most of the energy for the polyps. When corals are stressed, often because water temperatures are too high, they expel the microalgae within them. The structures then become transparent, leaving only the white skeletal corals. Bleached corals aren’t dead, but they are at great risk of starvation and disease until and unless new symbiont algae are acquired.

A new study by scientists at Uppsala University in Sweden investigated how different species of coral symbiont algae react to temperature stress. They discovered differences among symbiont cells that enable the prediction of how temperature stress tolerant the cells are. Such predictive ability could provide the means to identify and select more temperature-tolerant coral symbionts that could conceivably be introduced into coral host larvae in order to make corals more robust against climate change.

The research has a ways to go, but the new tools may help coral reef monitoring and increase the speed at which reef restoring efforts can create stocks of climate-resistant symbionts.

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Climate resilient microalgae could help restore coral reefs

Photo, posted September 28, 2009, courtesy of Matt Kieffer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Houseplants And Indoor Air Quality | Earth Wise

April 11, 2022 By EarthWise Leave a Comment

Many of us have houseplants in our homes and offices. The foliage and flowers add beauty and comfort to our indoor spaces. But it turns out that there are health advantages as well.

Many studies have demonstrated that indoor houseplants can help keep you happier and healthier by improving your mood, reducing fatigue, lowering stress and anxiety, and improving focus. Houseplants can also improve indoor air quality.

According to a new study by researchers from the University of Birmingham in the U.K. in partnership with the Royal Horticultural Society, ordinary houseplants can potentially make a significant contribution to reducing indoor air pollution.

The researchers tested three types of houseplants commonly found in homes in the U.K: Peace lily, corn plant, and fern arum. These plants are easy to maintain and not overly expensive.

In the study, the research team exposed these houseplants to nitrogen dioxide, which is a common indoor pollutant. The plants were isolated in a test chamber containing levels of nitrogen dioxide comparable to what might be in an office situated next to a busy road. The researchers found that all the plants were able to remove about half of the nitrogen dioxide in the chamber in just one hour.

In a poorly ventilated small office with high levels of air pollution, the researchers calculated that five houseplants would remove up to 20% of the nitrogen dioxide. In a larger space, the effect would be smaller – around 3.5% – although this figure could be increased by adding more plants.

Bringing nature indoors is one way to breathe cleaner air.

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Common houseplants can improve air quality indoors

Reducing air pollution with plants

Photo, posted September 21, 2014, courtesy of Olin Gilbert via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And Crops | Earth Wise

December 22, 2021 By EarthWise Leave a Comment

A new NASA study published in the journal Nature Food looks at the impact of global climate change on food crops. According to the study, declines in global crop yields are likely to become apparent by 2030 if high greenhouse gas emissions continue.

The study used advanced climate and agriculture models to predict the effects of projected increases in temperature, shifts in rainfall patterns, and elevated surface carbon dioxide concentrations from human-caused greenhouse gas emissions.

These climate changes would make it more difficult to grow corn in the tropics but would actually expand wheat’s growing range. The reduction in corn yields could be as much as 24% by late in the century. Corn Is grown all over the world and large quantities are produced in countries nearer to the equator. As temperatures rise in countries such as the US, Brazil, and China, yields are likely to decline because of the increased stress on the plants.

Wheat, which grows best in temperate climates may see a broader area where it can be grown as temperatures rise, but these gains are likely to level off by mid-century.

Rising temperature is not the only factor influencing crop yields. Rising carbon dioxide levels have a positive effect on photosynthesis and therefore on crop yields, especially for wheat. But changing rainfall patterns and rising temperatures can affect the length of growing seasons and accelerate crop maturity. This can result in the production of less grain than in a longer development period.

The changing climate has complicated effects on the growth of breadbasket crops and will be felt worldwide.

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Global Climate Change Impact on Crops Expected Within 10 Years, NASA Study Finds

Photo, posted September 8, 2004, courtesy of Lynn Ketchum/Oregon State University via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Seeds And Climate Change | Earth Wise

August 19, 2021 By EarthWise Leave a Comment

Farmers and agricultural communities around the world are on the frontlines of climate change. They are among the first to feel the impacts of hotter temperatures as well as more frequent and intense droughts and precipitation. These challenges pose a massive threat to both farmer livelihoods and global food security.

As the planet continues to heat up, many arid regions that already have marginal conditions for agriculture will be increasingly under stress. As a result, researchers from the Massachusetts Institute of Technology and the King Mohammed VI Polytechnic University in Morocco are working on a promising new way to protect seeds from this stress during their crucial germination phase. Their simple and inexpensive process, which was recently described in a paper published in the journal Nature Food, also provides plants with extra nutrition at the same.

The research team has developed a two layer coating for seeds designed for tackling issues related to drought. Drawing inspiration from natural coatings that occur on some seeds like chia seeds, the first layer is designed to protect the seeds from drying out. It provides a gel-like coating that grips any moisture that comes along and surrounds the seed with it. The second (inner) layer of the coating contains preserved microorganisms called rhizobacteria, as well as some nutrients to help the seeds grow.

The materials for the coatings are biodegradable, readily-available, and often used in the food industry already. According to researchers, early tests using common beans have demonstrated encouraging results in Morocco, and more field tests of the seeds are currently underway.

As the climate continues to change, more innovations like this will be necessary for global food security.

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Engineering seeds to resist drought

Photo, posted September 17, 2010, courtesy of Stacy via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Offsetting Reef Acidification | Earth Wise

August 13, 2021 By EarthWise Leave a Comment

The Great Barrier Reef is the world’s largest coral reef system. It is composed of nearly 3,000 individual reefs and 900 islands covering an area of more than 130,000 square miles. In recent times, it has been under unprecedented stress from ocean warming, tropical cyclones, sediment and nutrient runoff, marine pests, and ocean acidification.

Among these stressors, ocean acidification is one of the most significant threats to the long-term viability of the reef because acidification affects the ability of corals to rebuild and repair their structures and recover from bleaching events.

New research from CSIRO, Australia’s national science agency, studied the impact of artificial ocean alkalinization on the acidity of the waters in the Great Barrier Reef. The idea is to inject a source of alkalinity into the ocean, an accelerated version of a natural process that occurs from the chemical weathering of minerals under the sea.

The results of the study, published in the journal Environmental Research Letters, are that injecting an alkalinizing agent into the ocean along the length of the Reef would make it possible to offset ten years’ worth of ocean acidification based on the present rate of human-generated carbon emissions. Such an effort could use an abundant mineral resource like olivine, which is already mined near the Great Barrier Reef. Releasing 30,000 tons a day of the alkalinizing agent from an existing shipping line from a bulk carrier would reach almost the whole of the Great Barrier Reef.

In response to the declining health of coral reef ecosystems, many different intervention concepts and technologies are under consideration. The goal of these would be to minimize environmental pressures and enhance the resilience of the ecosystems.

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Projected acidification of the Great Barrier Reef could be offset by ten years

Photo, posted August 4, 2019, courtesy of Larry Koester via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Hardier Corals For Endangered Reefs | Earth Wise

July 26, 2021 By EarthWise Leave a Comment

Mass coral bleaching events are getting increasingly frequent as the oceans continue to warm, endangering coral reefs all over the world. The damage to Australia’s Great Barrier Reef has been enormous and in 2015, nearly half of Hawaii’s coral reefs were affected by a severe bleaching event.

Not all coral bleaching is permanent. Corals can sometimes recover. Some corals even seem to resist bleaching altogether. Researchers from the University of Pennsylvania studied these resilient corals to see just how effective they are in resisting the effects of climate change.

Their experiments sought to determine whether corals that seem to resist bleaching can be moved to other locations and used as the seed stock to repopulate degraded reefs.

The researchers identified coral colonies that resisted bleaching during the 2015 Hawaiian bleaching event and collected samples from them. They transplanted some of them to a second reef as well as putting other samples in laboratory tanks and simulating a bleaching event by raising the water temperature over a period of several days.

Careful tracking of the corals’ health showed that the bleaching-resistant corals stayed that way even in a new environment and under additional stress. They also studied how well the corals reproduced and found that the corals that spent time in a favorable new site before being subjected to stress demonstrated greater fitness and improved reproduction.

The study indicates that coral transplantation using colonies known to be resistant to bleaching may be an effective way to buy some time in preserving the world’s coral reefs. But global action on climate change is essential because even bleaching-resistant corals aren’t going to survive forever if ocean warming keeps increasing.

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Climate change-resistant corals could provide lifeline to battered reefs

Photo, posted November 29, 2012, courtesy of Robert Linsdell via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Helping Corals With Beneficial Bacteria | Earth Wise

March 31, 2021 By EarthWise Leave a Comment

A group of researchers at the King Abdullah University of Science and Technology in Saudi Arabia is exploring a novel technology to improve the health of corals. Around the globe, corals are being stressed by pathogens, toxins, and warming waters leading to widespread bleaching events.

The new idea is to introduce beneficial bacteria to the corals, thereby boosting the strength and resilience of their symbiotic partners. The concept is akin to the use of probiotics in plant science. Corals rely on bacterial and algal symbionts to provide nutrients, energy (through photosynthesis), toxin regulation, and protection against pathogens.

The researchers selected bacteria that are naturally symbiotic to specific coral species on reefs in the Red Sea, ensuring that no alien bacteria are accidentally introduced. A probiotic cocktail comprising six bacteria strains was used in a laboratory setting. Results in the lab have been promising so far, as they have observed dynamic and metabolic alterations to the corals that boosted their chances of survival under heat stress.

Success in the lab will need to be translated to success in the open oceans, which is challenging. Scaling up and seeding whole reefs might involve robots and artificial intelligence in order to deliver probiotics either into sediments or directly onto corals.

The use of beneficial microorganisms is not the solution to the global destruction of coral reefs. Only worldwide CO₂ mitigation can ultimately accomplish that. But the probiotic approach might buy corals some time as they deal with shifting environmental pressures and try to adapt to a changing world.

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Microbiome boost may help corals resist bleaching

Photo, posted March 18, 2018, courtesy of Steven dos Remedios via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Permanent Time Observation | Earth Wise

September 25, 2020 By EarthWise Leave a Comment

Americans have debated the value of daylight savings time going all the way back to Benjamin Franklin. As a country, we adopted the practice of changing our clocks twice a year in 1918.

Since the energy crisis of the 1970s, there have been a number of initiatives aimed at making daylight savings time permanent. However, there is also a growing movement to eliminate the practice entirely.

In August, the American Academy of Sleep Medicine published a position statement calling for the abolishing of daylight savings time in favor of fixed, national, year-round standard time.

The statement describes the adverse effects of the annual abrupt switch to daylight savings time, which range from increased risk of stroke and hospital admissions to sleep loss and increased production of inflammatory markers, which are one of the body’s responses to stress. It also cites studies that show that traffic fatalities increase by as much as six percent in the first few days following the change to daylight savings time. Other research shows that there is an 18% increase in adverse medical events related to human error in the week after switching to daylight savings time.

In July, a survey by the academy of more than 2,000 U.S. adults found that 63% support the elimination of seasonal time changes in favor of a national, fixed year-round time, and only 11% oppose the idea, but many of those in favor of the idea actually want permanent daylight savings time.

The sleep academy contends that permanent standard time is the best choice to most closely match our circadian sleep-wake cycle while daylight saving time results in more darkness in the morning and more light in the evening, disrupting the body’s natural rhythm.

Residents of Arizona and Hawaii get to sit out this debate since they don’t change their clocks.

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American Academy of Sleep Medicine calls for elimination of daylight saving time

Photo, posted May 28, 2018, courtesy of Kis Akos via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Immersion In Nature Is Good for You | Earth Wise

February 20, 2020 By EarthWise Leave a Comment

There is a growing body of research that shows that getting outdoors in nature can be good for people’s health and well-being. There are so many studies supporting this idea that policymakers, employers, and healthcare providers are increasingly considering this need for nature in how they plan and operate.

A new study of 20,000 people by researchers at the University of Exeter in the UK actually looked at how much exposure to nature was enough to make people say they feel healthy and have a sense of well-being. The answer turned out to be 2 hours a week. And the correlation was strong. People who didn’t meet that threshold did not report the benefits.

Studies have shown that time in nature – as long as people feel safe where they are – is an antidote for stress. It can lower blood pressure and stress hormone levels, reduce nervous system arousal, enhance immune system function, increase self-esteem, reduce anxiety, and improve mood. Most of these studies are correlational rather than causal, but the results tend to be robust.

Given all this, cities are adding or enhancing parks, and schools and other institutions are being designed with large windows and access to trees and green space. The Scandinavian tradition of “forest schools” – where learning takes place in natural settings outdoors -.is finding a home in the US. Japanese researchers study the effects of “forest bathing”, a poetic term for walking in the woods.

With two-thirds of humanity projected to be living in cities by 2050, we are awakening to the idea that we need to be able to spend time in nature for our own wellbeing, even if it’s just a walk in a park.

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Ecopsychology: How Immersion in Nature Benefits Your Health

Photo, posted November 6, 2011, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Europe Is Warming Faster Than Predicted

October 9, 2019 By EarthWise Leave a Comment

A new study has found that Europe is warming faster than even climate models projected. The number of summer days with extreme heat in Europe has tripled since the 1950s, while the number of days with extreme cold has decreased by factors of two or three depending on the region.

According to climate scientists at the Swiss Federal Institute of Technology in Zurich, the climate trends are much larger than what would come from natural variability and are a clear signal of climate change. Extremely hot days in Europe have become hotter by an average of more than 4 degrees Fahrenheit while extremely cold days have warmed by more than 5 degrees. The research examined data from weather stations across Europe from 1950 to 2018. Over 90% of the stations recorded increasing temperatures over time, a percentage much too high to be purely from natural climate variability. The results also showed that the region was warming even faster than climate models projected.

The research results come after an extremely hot summer in Europe. Southern France hit 114.8 degrees, a new record, in June. Germany, the Netherlands, and Belgium all recorded all-time national temperature highs. The National Oceanic and Atmospheric Administration recently announced that July was the hottest month ever recorded.

European summers and winters will only grow hotter in the coming years as climate change accelerates. The rapidly increasing temperatures will impact cities and people that are unprepared for them and pose real risks for residents in the coming decades. Extreme heat is dangerous because it stresses the human body, potentially leading to heat exhaustion or heat stroke.

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Europe warming faster than expected due to climate change

Photo, posted July 30, 2011, courtesy of Marcel de Jong via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Reducing Polar Bear Attacks

April 8, 2019 By EarthWise Leave a Comment

The increasing reduction of sea ice in the Arctic is changing the behavior of polar bears. Because they are spending more time on land, they are interacting with people much more frequently, occasionally with deadly results.

A study, published in 2017, looked at 144 years’ worth of polar bear attacks on humans in the Arctic. Between 1960 and 2009, there were a reported 47 attacks by polar bears on people – between 7 and 12 per decade. Between 2010 and 2014, as sea ice reached record lows, there were 15 attacks, a record for a four-year period. Since 2000, 88% of attacks have occurred between July and December, when sea ice is at its lowest level of the year.

Last July, a young male polar bear attacked and killed a man who was berry picking with his children. A month later, a mother polar bear attacked and killed an Inuit hunter and injured two others. This was the first known fatal attack by a mother polar bear.

As a result, Inuit communities in the Nunavut region are asking for higher legal polar bear harvest quotas, arguing that bear populations have increased to a dangerous level.

These recent human fatalities have also provided an impetus for developing new non-lethal conflict-resolution tools than can be used in northern communities before more people as well as bears are killed.

There are now polar bear patrol teams tasked with driving bears away from settlements. There is a bear hotline and electric fencing around sled dog compounds.

The changing face of the Arctic is creating growing stress on the polar bear population and on the people who make their home in that region.

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As Polar Bear Attacks Increase in Warming Arctic, a Search for Solutions

Photo, posted September 28, 2015, courtesy of Anita Ritenour via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Another Problem For Coral Reefs

April 5, 2019 By EarthWise Leave a Comment

Coral reefs around the world have been suffering in recent years from warming ocean temperatures as well as from increasing ocean acidification. Corals are very sensitive organisms that can only tolerate relatively slight changes in their environment. Thus, the majority of reef-building corals are found in tropical and subtropical waters with favorable conditions.

New research has confirmed that drastic changes in ocean salinity from, for example, severe freshwater flooding, provoke similar stress responses in corals as the heating that has resulted in freshwater bleaching and, eventually, coral death.

The coast of northeast Queensland in Australia has experienced abnormal monsoon-related freshwater flooding that caused extreme and sudden changes in the ocean salt concentration. In places, nearshore reefs were exposed to water with only half the normal ocean salinity. The result has been a shock response in corals that prevents normal cell function. Unlike their response to heat stress, corals exposed to reduced salinity experience a complete collapse of their internal cellular protein balance.

The central Great Barrier Reef has actually been relatively free from mass thermal bleaching events this Australian summer, but many coastal reefs instead have been battling dramatic changes in water conditions as a result of massive plumes of floodwater.

The wild weather in Australia is undoubtedly associated with the changing climate and this new research shows that it is leading to yet another threat to the world’s coral reefs. With the frequency and severity of heavy rainfall and runoff events predicted to continue to increase over the next few decades, proactive measures to increase the resiliency of coral reefs are needed more than ever.

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