Monday, August 02, 2021

Biofertiliser for better farms

Organic nitrogen source for carbon-rich fertile soils

FLINDERS UNIVERSITY

Cyanobactereia — IMAGE: CYANOBACTEREIA view more
CREDIT: FLINDERS UNIVERSITY

While agricultural production around the world struggles with declining soil health, Australian-led research is investigating production of a sustainable organic nitrogen fertiliser made from aquatic cyanobacterial biomass – ideally suited for badly degraded areas reliant on chemical fertilisers.

“Many soils are degraded and becoming less fertile. This challenges agriculture to produce sufficient high-quality food to feed the continuously growing population, which is further exacerbated by climatic instability threatening crop production,” says Flinders University researcher Dr Kirsten Heimann.

Scientists in Australia, US and Europe are testing a new biofertiliser made from a fast-growing freshwater cyanobacterium Tolypothrix, which can fix nitrogen from the atmosphere without the need for additional nitrogen fertilisation, making the biomass inexpensive to produce compared to alternative microalgal and macroalgal biofertilisers.

This form of non-toxic blue-green algae can be cultivated in freshwater, and even slightly saline or industrial wastewater such as from coal-fired power stations, the research team has found. Capturing biofuel may also be used to offset production costs.

Energy inputs for the production of Tolypothrix biomass can be offset by producing biogas, essentially a methane-rich gas for either drying the biomass to extract high-value health supplement phycocyanin or to produce carbon and nitrogen-rich liquid and solid biofertilisers to remediate soil infertility.

In a recent paper in Chemosphere, Dr Heimann and colleagues in Australia, the US and Spain investigate Tolypothrix production as a sustainable solution for biological soil improvement, which when combined with biogas or the spirulina-like nutritional powder promises “strong economic returns for regional and remote farming communities”.

“Australian soils, in particular in the marginal wheat belt in Western Australia, are structurally degraded, which cannot be overcome by applications of synthetic fertilisers,” says Associate Professor Heimann, from the Flinders University Centre for Marine Bioproducts Development in South Australia.

“To improve soil structure, organic carbon applications are required to return the soils’ capacity to sustain a healthy soil microbiome and to improve the soils’ cation exchange of nutrients and water-holding capacity.”

Researchers say conversion of pond-produced cyanobacterial biomass produced on farming land would provide a major in-situ source of renewable nitrogen-rich fertiliser, also helping to reduce carbon emissions from chemical fertiliser production and transport.

Higher energy and food demands are forecast as a consequence of expected global population growth, predicted by the UN to reach 8.5 billion in 2030, 9.7 billion by 2050 and 10.9 billion in 2100.

These projections encourage research into biofertilizer and biogas production through sustainable energy generation using waste organic material of controlled production of biomass such as microalgae and multicellular cyanobacteria.

Researchers have previously reported photosynthetic fixation of CO2 by cyanobacteria of 100 to >200 tons CO2 ha−1 y−1 under outdoor cultivation conditions in open ponds, raceway ponds, photobioreactors and attached growth bioreactors.

Unlike many cyanobacterial species, Tolypothrix sp., a freshwater cyanobacterium, is filamentous and forms aggregates that self-flocculate, making it very easy to harvest from suspension cultures, reducing dewatering costs by up to 90%, studies suggest.

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The article, Biomass pre-treatments of the N2-fixing cyanobacterium Tolypothrix for co-production of methane (2021) by C Velu, OP Karthikeyan, DL Brinkman, S Cirés and K Heimann has been published in Chemosphere (Elsevier) DOI: 10.1016/j.chemosphere.2021.131246

Acknowledgements: This research received funding from the Advanced Manufacturing Cooperative Research Centre (AMCRC) and associated Universities.

JOURNAL

Chemosphere

DOI

10.1016/j.chemosphere.2021.131246

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Cells

ARTICLE TITLE

Biomass pre-treatments of the N2-fixing cyanobacterium Tolypothrix for co-production of methane

ARTICLE PUBLICATION DATE

31-Oct-2021

CORPORATE WELFARE BUMS

US subsidies boost the expected profits and development of new oil and gas fields

Peer-Reviewed Publication

IOP PUBLISHING

Researchers at the Stockholm Environment Institute (Somerville and Seattle, USA) and Earth Track, Inc. (Cambridge, MA, USA) examined 16 subsidies and environmental regulatory exemptions, providing one of the first estimates of how government subsidies will affect investment decisions for new gas fields in the coming decade. Their results are published on 29 July 2021 in the IOP Publishing journal, Environmental Research Letters.

Despite repeated pledges to phase out “inefficient” fossil fuel subsidies, the United States — the world’s largest current oil and gas producer — continues to provide billions of dollars each year to the oil and gas industry through various support measures. The study not only looks at tax incentives, but it is one of the first of its kind to also account for the effects of regulatory exemptions that reduce the costs for hazardous waste and wastewater management for oil and gas producers.

“Besides two federal tax incentives that have existed since 1916, we were surprised to find that less widely recognized forms of government support can also be highly beneficial,” said SEI Scientist Ploy Achakulwisut, a lead author of the paper. “The public ends up footing the bill for services like well closure and hazardous waste disposal – directly with their tax money and indirectly with their health.”

For their analysis, the study’s authors developed a cash-flow model, using Rystad Energy’s UCube database and their own assumptions regarding commodity prices. They then evaluated the effects of 16 subsidies and regulatory exemptions on the expected investment returns of thousands of oil- and gas-producing fields that are projected to be developed between 2020 and 2030.

The results show that, depending on future oil and gas prices and the minimum required rates of return, subsidies (including exemptions) either encourage more extraction than would otherwise be economically viable, or flow to excess profits. In the former instance, subsidies would help lock in higher greenhouse gas emissions, as well as increase air and water pollution and health risks. In the latter case, they would not be fulfilling their stated economic purpose.

For example: at 2019 oil and gas prices – or $64 per barrel of oil and $2.6 per mmbtu (million British Thermal Units) of gas – only 4% and 22% of new oil and gas resources would be subsidy-dependent. In this case, over 96% of subsidy value would flow directly to excess profits. This scenario assumes that investors require a 10% minimum rate of return, or “hurdle rate”.

However, if oil and gas prices are as low as they were in 2020 – or $40 per barrel of oil and 2 per mmbtu of gas – then more than 60% of new oil and gas resources would depend on subsidies to be economically viable. This scenario assumes that investors would require a higher 20% hurdle rate, which may already be the case as risks increase for oil and gas investments.

The authors also examine the extent to which subsidies to fossil-fuel producers affect CO2 emissions by depressing oil and gas market prices and incentivizing higher consumption. They estimate that, under a 10% hurdle rate, the subsidy-induced decrease in oil price could result in an additional 374 million barrels of oil being burned in 2030, adding 150 million tonnes of CO2 emissions.

“In the wake of the COVID-19 pandemic, our results illustrate how different choices about economic recovery and tax reform can shape the US oil and gas industry and energy infrastructure in the years to come,” said co-lead author and SEI Senior Scientist Peter Erickson. “In addition, fossil fuel subsidies can have symbolic effects, since their continued existence may be read by other nations as a sign that the US is not taking its commitments to subsidy reform, or to climate action, as seriously as it should be.”

“Good governance requires transparency on who is receiving subsidies,” added co-author Doug Koplow from Earth Track. “Our study helps to shine a light on the effects of subsidies on the expected returns of US oil and gas producers and their investment decision-making. The same methods could be applied to inform ongoing subsidy reform efforts in other countries.” G7 governments continue to provide billions of dollars in subsidies each year.

###

JOURNAL

Environmental Research Letters

DOI

10.1088/1748-9326/ac0a10

METHOD OF RESEARCH

Data/statistical analysis

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Effect of subsidies and regulatory exemptions on 2020–2030 oil and gas production and profits in the United States

ARTICLE PUBLICATION DATE

28-Jul-2021

Marine ecologists reveal mangroves might be threatened by low functional diversity of invertebrates

Peer-Reviewed Publication

THE UNIVERSITY OF HONG KONG

Mangrove forests were once dominant in the tropics but have recently been disappearing at alarming rates worldwide. Although this threatened ecosystem supports a broad range of specialised invertebrates, little is known about the impact of mangrove deforestation on the functional diversity and resilience of these resident fauna.

The International Day for the Conservation of the Mangrove Ecosystem (also known as the World Mangrove Day), declared by UNESCO and celebrated every year on 26th July, aims to raise awareness on the importance of mangrove ecosystems. Mangroves are more than just trees, together they form a unique, special and vulnerable habitat. Their ecological functioning depends upon the mutual relationships between their floral and faunal components, and there is no viable mangrove forest without a healthy community of invertebrates sustaining it.

To address this question, which is crucial in order to manage pristine mangroves and rehabilitate degraded ones, Dr Stefano CANNICCI (Associate Director of the Swire Institute of Marine Science and Associate Professor from the Research Division for Ecology & Biodiversity, The University of Hong Kong), along with Professor Joe Shing Yip LEE (Professor and Director, Simon FS Li Marine Science Laboratory, School of Life Sciences, The Chinese University of Hong Kong) and their colleagues compiled a dataset of 209 crustacean and 155 mollusc species from 16 mangrove forests around the world. They found that mangroves, when compared with other ecosystems, are among those with the lowest functional redundancy among resident fauna recorded to date, which suggests that these coastal vegetations are one of the most precarious ecosystems in the world in the face of the recent anthropogenic changes. Thus, a high functional redundancy is a sort of ‘ecological insurance’ for a given forest, since if one species is lost, another can fulfil its function, ultimately keeping the ecosystem viable.

CAPTION

Large crabs, such as Chiromantes haematocheir, constantly rework the sediment, providing nutrients and oxygen to the mangrove trees.

CREDIT

Stefano Cannicci

Diversity: The key to survival

The authors classified these species into 64 functional entities based on unique combinations of three functional traits: feeding habits, behavioural traits potentially affecting ecosystem characteristics, and micro-habitat. More than 60% of the locations showed no functional redundancy, i.e., most of the functional entities at those locations consisted of only one species, with the notable exceptions being locations in South America, the eastern Indian Ocean and the western Pacific Ocean. On average, 57% of the functional entities are performed by a single species, suggesting that even a modest local loss of invertebrate diversity could have significant negative consequences for mangrove functionality and resilience, because invertebrates are crucial for the mangrove nutrient cycling and for oxygen provision to the tree roots and these functions will be lost with a decrease in functional diversity.

Moreover, the low functional diversity of the resident invertebrates indicates that mangroves are among the most vulnerable ecosystems on the planet. Nonetheless, some small mangrove patches, such as those in Hong Kong and Mozambique, harbor multifunctional invertebrate assemblages that may serve as biodiversity reservoirs, which could prove critical for future conservation efforts. Mangrove trees can be replanted but the local invertebrate fauna needs to naturally recruit the newly replanted sites. Without faunal recruitment, mangrove will not be able to develop, due to the lack of nutrients and oxygen in the soil. By contrast, some large forests, such as those in Cameroon, were characterised by low invertebrate functional diversity. Taken together, the findings suggest that faunal functional diversity may be a better measure of mangrove resilience than the conventional indicator of forest size. One of the most important messages to take away from this study is that, although the mangroves in Hong Kong are very small, they are very diverse, and they are still home for a lot of species, which perform multiple functions in the environment. Therefore, the mangroves in Hong Kong are the last pristine, and natural mangroves in the Pearl River Delta, and they could be sources of populations that can re-populate mangroves even in mainland China.

According to the authors, studying the functional diversity of the resident faunal assemblages is crucial for assessing the vulnerability of mangrove forests to environmental change and for designing effective management, conservation, and restoration plans. At present, the health and resilience of mangrove forests around the world are assessed through their overall increase in area. This approach, however, does not consider the real viability and functionality of those forests. A mangrove forest is not just a group of trees, but a complex ecosystem also built upon healthy faunal communities and on the interaction between such communities and the trees. Mangrove management and rehabilitation projects need to take into account not just the increase in size of a mangrove, but also the stability and redundancy of its faunal component.

CAPTION

Invertebrate animals influence many ecological functions of mangrove forests, like the change in surface topography caused by the mounds of burrowing crustaceans at Sam A Chung, located in the northeastern part of Hong Kong.

CREDIT

Joe S Y Lee

The findings were recently published in The Proceedings of the National Academy of Sciences (PNAS), the official journal of the National Academy of Sciences (NAS).
The journal paper can be accessed from here: https://doi.org/10.1073/pnas.2016913118

For media enquiries, please contact Ms Casey To, External Relations Officer (Tel: 3917-4948; email: caseyto@hku.hk ) and Ms Cindy Chan, Assistant Communications Director of Faculty of Science (Tel: 3917-5286; email: cindycst@hku.hk ) from HKU, or Mr Henry Kwan, Public Relations Executive, Communications and Public Relations Office (Tel: 3943-1719; email: henrykwan@cuhk.edu.hk) from CUHK.

Images download and captions: https://www.scifac.hku.hk/press

JOURNAL

Proceedings of the National Academy of Sciences

DOI

10.1073/pnas.2016913118

ARTICLE TITLE

A functional analysis reveals extremely low redundancy in global mangrove invertebrate fauna

ARTICLE PUBLICATION DATE

9-Aug-2021

FOR PROFIT HEALTHCARE

Diabetes patients in high-deductible health plans 28% more likely to skip their medications due to cost: Harvard study

Peer-Reviewed Publication

PHYSICIANS FOR A NATIONAL HEALTH PROGRAM

For Americans with diabetes, being enrolled in a high-deductible health plan (HDHP) substantially increases the risk of not taking prescribed medications due to cost, according to a new study conducted by researchers at Harvard Medical School that was published today in the Journal of General Internal Medicine. HDHPs, which now account for half of all commercial health insurance plans, require patients to pay for all care out of pocket until a plan’s deductible is reached. Only after the deductible is reached (typically $1,300 for an individual and $2,600 for a family) does insurance begin to cover medical costs.

The study found that among all patients with diabetes, 20% of those enrolled in a HDHP reported forgoing medications due to cost, compared with 16% of those in a traditional commercial plan—a 28% higher rate of missing medication for those with a high deductible. Among patients specifically taking insulin for diabetes, 25% of HDHP enrollees were unable to afford their medication, compared with 19% of those in a traditional plan—a 31% higher rate of missing medications.

The study used federal survey data on more than 7,000 adult patients with diabetes who were enrolled in a commercial health insurance plan, either with or without a high deductible. The researchers examined how often patients reported not taking prescribed medications because they could not afford it, comparing responses between those in a HDHP and those in a traditional plan without a high deductible.

“Taking prescribed medications is essential for maintaining good health for patients with diabetes,” said Dr. Vikas Gampa, a primary care doctor and instructor in medicine at Harvard Medical School, now at the Massachusetts General Hospital. “Our results show that high-deductible health plans, particularly in this period of escalating prices for diabetes medication, are discouraging patients from getting the medications they need and thus they are placing patients with diabetes at risk.”

The study also found that among the diabetic patients they studied, those that could not take their medication as prescribed because they could not afford it were more likely to have one or more emergency department visits, and potentially more hospitalizations per year, than patients who were not forced to skip their medications. “Putting up financial barriers to care in order to save plans money—as high-deductible plans do—not only takes a medical toll on patients, it is also short-sighted because doing so actually increases other health care costs such as covering emergency department visits,” commented Dr. Gampa.

The study authors believe that the new data are important for patients, doctors, and policy makers. “Patients with diabetes should recognize that a high-deductible plan will put them at risk for missing or delaying their medications, and doctors need to recognize that their patients with these plans may not be able to adhere to treatment plans,” said the study’s senior author, Dr. Danny McCormick, an associate professor of medicine at Harvard Medical School and a primary care physician at the Cambridge Health Alliance. “Ultimately, policy makers need to enact reforms that discourage health plans from implementing financial barriers that block access to needed care, such as high-deductible plans. Our results suggest that policy makers must enact reforms that control rapidly escalating prices for diabetic medications.”

* * * * * *

“Association Between High Deductible Health Plans and Cost-Related Non-Adherence to Medications Among Americans with Diabetes: An Observational Study,” Charlotte Rastas, MD, MSc, Drew Bunker, MD, Vikas Gampa, MD, John Gaudet, MD, Shirin Karimi, MD, Ariel Majidi, MP, Gaurab Basu, MD, MPH, Adam Gaffney, MD, MPH and Danny McCormick, MD, MPH; Journal of General Internal Medicine, published online first July 29, 2021

The full text of the article is available to media professionals upon request. Please contact Clare Fauke, clare@pnhp.org. 312-782-6006.

JOURNAL

Journal of General Internal Medicine

DOI

10.1007/s11606-021-06937-9

METHOD OF RESEARCH

Survey

SUBJECT OF RESEARCH

People

ARTICLE TITLE

“Association Between High Deductible Health Plans and Cost-Related Non-Adherence to Medications Among Americans with Diabetes: An Observational Study

ARTICLE PUBLICATION DATE

29-Jul-2021

Disclaimer: AAAS and Eure

HKU Ecologist applied a novel statistical method to analysing causal inference and revealed importance of climate change in controlling deep-sea biodiversity

Peer-Reviewed Publication

THE UNIVERSITY OF HONG KONG

ecosystem — IMAGE: AN EXAMPLE OF DEEP-SEA SOFT SEDIMENT ECOSYSTEM. view more
CREDIT: PHOTO CREDIT: NOAA OER AND OCEAN EXPLORATION TRUST; A. THURBER CAMERA LOAN. COURTESY OF LISA LEVIN

Which of temperature or food is more important for the richness of deep-sea animals? Dr Moriaki YASUHARA from the School of Biological Sciences, the Research Division for Ecology & Biodiversity, and The Swire Institute of Marine Science, The University of Hong Kong (HKU), in collaborating with Hideyuki DOI from University of Hyogo and Masayuki USHIO from Kyoto University, used long-term fossil dataset and novel statistical method to detect causality and found climate control of deep-sea biodiversity.

Deep-sea cover >90 % of the ocean. So, understanding biodiversity drivers in deep-sea is critically important to project future changes in the function of Earth's ocean system. Recently, two main factors of the deep-sea biodiversity control have been actively debated, which are (1) food supply via marine snow (aka sinking particulate organic carbon originated from surface primary production) that is the main food source for deep-sea animals (given no sun light penetration and so no phytoplankton production in deep sea); and (2) climate-driven deep-sea temperature change. These two hypotheses of marine-snow or temperature control of deep-sea biodiversity are difficult to be fully tested by traditional modelling framework because the environment-diversity relationship that facilitates deep-sea biodiversity can be complex.

The research, published in Biology Letters, used long-term fossil records from sediment cores and recently developed statistical method that can detect causality in a complex system instead of simple correlation (degree of linear relationship between two variables) to address this issue of marine-snow or temperature control of deep-sea biodiversity. The research team used benthic foraminifera (small shelled protist) as indication for the deep-sea fossil biodiversity time series and applied Convergent Cross Mapping (CCM) for the causality detection, and the results detected causality of temperature on deep-sea biodiversity but not of marine snow, which is supporting evidence that climate change affected long-term changes in deep-sea biodiversity. This temperature-diversity relationship detected indicates that ongoing and future human-induced climate change may affect deep-sea ecosystems via changes in global deep-water circulation rather than those in surface primary production. However, their study is based on a relatively limited number of data, and we need further comprehensive studies with better spatial and temporal coverage to confirm the generality of this conclusion.

In addition, this study is the first application of the causal inference method, CCM, to deep-sea long-term fossil time series from sediment cores. They successfully showed that this framework of using CCM on diversity time series can applicable not only to relatively short ecological-biological time series, but also long paleontological-paleoclimatological time series broadly.

"It's a long term debate which of temperature or marine snow is the main driver of deep-sea biodiversity. Our new causality analysis result is the strong support for the temperature hypothesis. ” co-lead author Moriaki Yasuhara concluded.

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About the journal paper
Citation: Hideyuki Doi, Moriaki Yasuhara, Masayuki Ushio (2021) Causal analysis of the temperature impact on deep-sea biodiversity. Biology Letters.

The journal paper can be accessed from here: https://royalsocietypublishing.org/doi/10.1098/rsbl.2020.0666

For more information about Dr Moriaki Yasuhara’s research, please visit: https://moriakiyasuhara.com

Images download and captions: https://www.scifac.hku.hk/press

For media enquiries, please contact Ms Casey To, External Relations Officer of HKU Faculty of Science (tel: 3917 4948; email: caseyto@hku.hk) / Ms Cindy Chan, Assistant Director of Communications of HKU Faculty of Science (tel: 3917 5286; email: cindycst@hku.hk) or Dr Moriaki Yasuhara (email: yasuhara@hku.hk).

JOURNAL

Biology Letters

DOI

10.1098/rsbl.2020.0666

ARTICLE TITLE

Causal analysis of the temperature impact on deep-sea biodiversity

ARTICLE PUBLICATION DATE

20-Jul-2021

More tolerant primates have a greater need to communicate vocally, new study shows

Peer-Reviewed Publication

UNIVERSITY OF YORK

Primates who are more tolerant of each other use vocal communication more than their stricter counterparts, research from the University of York shows.

The study looked at how dominant primates behave towards those of lower status, with some demanding deference and punishing challenges from subordinates harshly (despotic), whilst others are more relaxed (tolerant).

Japanese macaques are an example of a despotic species in this study, while black howler monkeys are an example of a tolerant species.

Researchers say this characteristic called “dominance style” is an important factor in understanding the evolution of communication. They expected that tolerant primates would use more communication than despotic primates to achieve their goals or to maintain their dominant position, instead of using aggression.

Using behavioural data from 26 primate species, the researchers quantified dominance style for the first time in many of these species.

Lead author, Dr Eithne Kavanagh a former PhD student from the Department of Psychology said: “We found evidence that dominance style was related to vocal communication at both individual and species levels.

“Notably, we found that more despotic species had richer repertoires of hierarchy-related calls in their evolved vocal systems, but that individuals who were more tolerant of lower-ranking partners vocalized at a higher rate.

“This indicates that tolerance within a relationship may place pressure on the dominant partner to communicate more during social interactions.”

The study concluded that overall, the findings suggested that the strictness of the dominance relationships of individuals and species provides important context for understanding primate vocal usage and evolution.

Partners in the research included Professor Katie Slocombe from the University of York, Dr Adriano Lameira from University of Warwick and Dr Sally Street from Durham University. This project was only possible with a great collaborative effort, with 64 primate researchers from 59 institutions working together to build the data set necessary to test these ideas.

The paper called, “Dominance style is a key predictor of vocal use and evolution across non-human Primates,” is published in Royal Society Open Science.

JOURNAL

Royal Society Open Science

DOI

https://doi.org/10.1098/rsos.210873

ARTICLE TITLE

Dominance style is a key predictor of vocal use and evolution across non-human Primates

ARTICLE PUBLICATION DATE

27-Jul-2021

Artificial light disrupts dung beetles’ sense of direction

Peer-Reviewed Publication

LUND UNIVERSITY

Dung beetle 1 — IMAGE: A NOCTURNAL DUNG BEETLE CLIMBING ATOP ITS DUNG BALL TO SURVEY THE STARS BEFORE STARTING TO ROLL view more
CREDIT: CHRIS COLLINGRIDGE

For the first time, researchers have been able to prove that city lights limit the ability of nocturnal animals to navigate by natural light in the night sky. Instead, they are forced to use streetlamps, neon light or floodlights to orient themselves. The findings are published in Current Biology.

Some animals, including migratory birds, seals and moths, use light from the moon, stars and Milky Way to navigate at night. A team of researchers at Lund University in Sweden and the University of the Witwatersrand in South Africa have now shown how nocturnal dung beetles are forced to search for cues in their immediate surroundings when they can no longer navigate using natural light from the night sky.

“These beetles are forced to abandon their celestial compass and orient using artificial light instead”, says James Foster at the University of Würzburg in Germany, who led the study during his time at Lund University.

The Lund University team previously received a great deal of attention for their investigation into how dung beetles orient themselves using the Milky Way as they roll their balls of dung over the South African savannah. The new study investigates how light pollution affects the beetles’ ability to orient themselves according to compass references in the night sky.

The experiments took place over several nights in two different locations in South Africa. One location was a light-polluted site on the roof of a building in central Johannesburg, while the other was in rural Limpopo, where the stars illuminated an otherwise dark sky. The result was unambiguous: the dung beetles were unable to use their celestial compass in the presence of light pollution. Instead, they moved towards the streetlights and illuminated buildings. In addition, several individuals often moved towards the same light source in the surroundings. Under natural conditions, these beetles tend to disperse in all directions, steering clear of one another and thereby avoiding confrontation.

“We believe that light pollution can have an equivalent effect on moths, forcing them to abandon their compass and fly towards the artificial light, in order to have any signals at all to orient themselves by”, says Maria Dacke, professor at Functional zoology at Lund University.

According to the researchers, it is likely that the animals living on the outskirts of cities are the ones most affected by light pollution—without stars or streetlights to guide them.

“In our experiments, we observed how beetles that viewed direct light pollution behaved unnaturally, but remained oriented. The ones that could only see the light-polluted night sky, but could not see any illuminated buildings or streetlights, became completely disoriented”, concludes Foster.

CAPTION

James Foster and Marie Dacke performing orientation experiments at a dark-sky site in rural Limpopo

CREDIT

Chris Collingridge

CAPTION

Claudia Tocco on the same night performing the same experiment at our light-polluted site: the roof of the University of the Witwatersrand in central Johannesburg

CREDIT

Marcus Byrne

DOI

10.1016/j.cub.2021.06.038

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Light pollution forces a change in dung beetle orientation behavior

ARTICLE PUBLICATION DATE

29-Jul-2021

COI STATEMENT

(Conflict of Interest)

Khepri (Egyptian: ḫprj, also transliterated Khepera, Kheper, Khepra, Chepri) is a scarab-faced god in ancient Egyptian religion who represents the rising or morning sun. By extension, he can also represent creation and the renewal of life.

Major cult center: Heliopolis

Offspring: All gods (some accounts), Ma’at

Parents: Nut (some accounts)

Symbol: scarab, blue lotus

Khepri - Wikipedia

Study: Buffer zones, better regulation

needed to prevent agricultural pollution in

rivers, streams

Peer-Reviewed Publication

OREGON STATE UNIVERSITY

Greater buffer zones around bodies of water and more consistent enforcement of water protection regulations are needed to reduce agriculture-based pollution in the Western U.S., a recent review from Oregon State University found.

Prior research has shown that agricultural pollution, both from croplands and rangelands, is the cause of 48% of water-quality impairment in U.S. surface waters, which in turn disrupts habitat for fish and insects and reduces biodiversity in aquatic environments.

The OSU paper, featured earlier this month on the cover of the journal Water, reviewed more than 40 case studies on the impacts of agriculture on water quality. Specifically, researchers looked at studies that related agricultural management practices to aquatic responses in rivers and streams; and related livestock rangeland uses to biotic responses within rivers and streams as well as in riparian zones, the areas bordering rivers and streams.

The latest national assessment of streams and rivers in the lower 48 U.S. states found that only 26-30% of the entire stream and river length was in good condition for the insects and fish that inhabit them. Still, researchers are optimistic that with proper mitigation, led by local communities, the U.S. can improve aquatic habitat and boost the health of water-dwelling species.

“What I see is that there are still a lot of pretty good places; but there are still a lot of places where, regardless of laws and regulations and mitigation actions, there’s still some work that remains,” said lead author Robert Hughes, who holds a courtesy appointment as an associate professor in the Department of Fisheries, Wildlife, and Conservation Sciences in OSU’s College of Agricultural Sciences. “We can do better. We already know how.”

The same national assessment found that 44% and 37% of total stream and river length was in poor condition for insects and fish, respectively.

Study authors say that point sources — specific outlets where pollution enters the water — are relatively easy to identify and treat, but the challenge with agricultural pollution is that it occurs over diffuse areas of land, especially throughout the Western U.S. This includes row crop fields that drain into rivers and streams, as well as rangelands where cattle graze and defecate directly in and near bodies of water.

Researcher Robert Vadas, Jr. from Washington co-authored the study and emphasized that regulation of agricultural pollution in Washington lags behind regulation of urban and forestry land uses.

“The best solution would be to give the riparian sectors back to the streams,” Hughes said, referring to the floodplain areas that extend outward a short distance from riverbanks. “We could have easements; we could pay farmers to put that land out of crop production; just provide a little bit of a buffer, a little bit of shade, maybe some wood to fall in and provide habitat for fishes.”

Better fences and herding to keep cattle out of rivers and streams would also make a difference, he said.

“If you look at the sites that are in good condition, it’s because they’ve had watersheds that are protected and riparian zones that are protected,” Hughes said. “They’re not perfect; they’re still used by farmers, ranchers and loggers, but they’re in significantly better shape.”

In Oregon, a 2009 study found that agricultural lands accounted for 80% of the impaired stream length in the Willamette Basin, despite representing only 30% of the total length.

But Hughes cites the Willamette River as an example of positive change. Significant rehabilitation projects have cleaned up point sources of pollution and improved fish habitat by planting trees, opening up side channels and removing road crossings that blocked fish migration.

“You can now swim and fish in the Willamette; 70 years ago it was an open sewer,” he said. “We still have some problems, of course, but we have made some big strides.”

Hughes recognizes the potential barriers to convincing farmers to allow some of their farmland to return to nature, as well as the cost of infrastructure needed to provide more protection for rivers and streams.

The solutions need to come from within local communities themselves, he said, not as mandates handed down from outside government agencies.

“What we’ve done most successfully in Oregon is watershed councils, where local people get together and decide what they can do, and talk about, ‘We tried this; we can make this improvement,’” Hughes said. “That’s the way to do it. We’re wired to not listen to something that comes from above.”

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JOURNAL

Water

DOI

10.3390/w13141901

METHOD OF RESEARCH

Literature review

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Agricultural Effects on Streams and Rivers: A Western USA Focus

ARTICLE PUBLICATION DATE

9-Jul-2021