Brazil must reinforce protection of forests to meet climate change mitigation goals, study warns

In an article published in Perspectives in Ecology and Conservation, researchers discuss CO2 emission reduction challenges and solutions.

Fundação de Amparo à Pesquisa do Estado de São Paulo

 

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A deforested area in the vicinity of Antimary State Forest, Acre state, North Brazil 

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Credit: Beatriz Cabral/INPE

As it prepares to host the 30th Conference of the Parties to the United Nations Framework Convention on Climate Change (UNFCCC COP 30, the first COP to be held in the Amazon) in November 2025, Brazil is at a crucial moment. Its greenhouse gas emission reduction targets are still within reach, but socioenvironmental actions and policies focusing on conserving or restoring forests and biomes need to be strengthened. This is one of the key points made by Brazilian scientists in an article published in the journal Perspectives in Ecology and Conservation.

The authors are affiliated with the National Space Research Institute (INPE) and the National Disaster Surveillance and Early Warning Center (CEMADEN).

The article addresses challenges in conserving and restoring Brazilian biomes, combating deforestation and forest degradation, restoring native vegetation, and promoting vegetation regrowth in secondary forests. It advocates strengthening and expanding policies to maintain ecosystem services, implementing consistent mechanisms to attract investment in restoration activities and payment for environmental services in all biomes, fostering bioeconomy initiatives, and creating new environmental protection areas.

“The article reflects a collaborative study designed to provide an overview of deforestation, degradation and restoration of biomes, and how these relate to Brazil’s efforts to pursue sustainable development and achieve its carbon emission goals,” said Débora Joana Dutra, first author of the article and a PhD candidate at INPE with a scholarship from FAPESP.

For biologist Liana Oighenstein Anderson, Dutra’s thesis advisor and a researcher at CEMADEN, even when there are preventive measures, they are insufficient to tackle the challenges posed by climate change. “The wildfires seen this year in the Amazon and Pantanal are a case in point. Prevention wasn’t sufficient to contain the alarming numbers. When we do estimates like those in the study, we get the feeling we’re being highly conservative in light of what’s actually happening and the challenges Brazil faces,” Anderson told Agência FAPESP. 

This has been a record year for fires in Brazil, with 65,325 fire incidences reported in the first seven months – the highest number for almost 20 years. The previous record was 69,184 in the corresponding period of 2005, according to data from INPE. The Amazon and Cerrado biomes are the worst hit (28,396 and 22,217 respectively).

In the Pantanal, the number of reported fires in the period reached 4,756, the highest since records began in 1998. The highest annual total in this biome was recorded in 2020.

“In 2020, fires in the Pantanal, which is in Brazil’s central region, drew the world’s attention and led to a number of reactions. For example, the Ministry for Science and Technology created Rede Pantanal, and the state of Mato Grosso do Sul implemented an integrated fire management plan. In 2023, the federal government announced a management plan for the biome, and Mato Grosso do Sul declared a state of emergency in April. So there have been actions relating to management, governance and regulation to try to avoid fires, but unfortunately they aren’t enough. We’ve seen progress, but we need better governance, improved strategies, and more funds. Everything must be done faster,” Anderson said.

For Luiz Aragão, last author of the article and a researcher at INPE, the study is a wakeup call to society regarding greenhouse gas emissions and related issues. “Society must address the problem not just from the environmental standpoint but also socioeconomically. It’s all connected. Deforestation, for example, tends to be followed by fire, which is a public health hazard and degrades the forest. Degraded land where the forest has been cleared has less potential to provide ecosystem services, such as the water cycle and biodiversity, which safeguard the quality of life for local communities and exert a significant influence on economic activity,” he said.

Changes in land use and land cover (such as deforestation to raise cattle and grow crops, or forest degradation) are the main sources of greenhouse gas emissions in Brazil. As a signatory to the Paris Agreement, negotiated at the 2015 UN climate change conference in France, Brazil undertook to help keep global warming at or below 1.5 °C compared with the preindustrial level (1850-1900), but the average temperature rise has far surpassed this limit in recent months.

The COP30 agenda includes a review of the Paris Agreement, which requires all signatories to commit to 2030 greenhouse gas emission reduction goals. Brazil has promised 53% compared with 2005. Nevertheless, net emissions of carbon dioxide (CO2) due to land use and land-cover changes doubled between 2017 and 2022, according to the Greenhouse Gas Emission Estimating System (SEEG). As for restoration, Brazil has promised to rewild 12 million hectares of former native forest (an area almost the size of Portugal).

Difficulties

According to the article, halting or reversing the growth of deforestation in all six biomes is a major challenge. The authors note that the destruction of native vegetation has averaged 2 million hectares per year or more since 2016, when Brazil submitted its nationally determined contribution under the Paris Agreement rules.

In 2022 alone, some 2.8 million hectares were deforested, mainly in the Amazon and Cerrado. This was the highest rate since 2008 and represented 23% of Brazil’s restoration goal. In addition, restoration of native vegetation is required in some 16 million hectares inadequately conserved as “legal reserves” on private property, more than half in the Amazon and 25% in the Cerrado.

Another finding highlighted by the researchers is the growth of secondary forest areas, which have high carbon capture capacity but are not protected by specific legislation. According to the article, 5.46 million hectares of secondary forest grew outside public land between 2017 and 2022 – 40% in the Amazon, 36% in the Atlantic Rainforest biome, and 19% in the Cerrado. Although this is almost half of Brazil’s restoration goal, maintenance of secondary forests as carbon sinks is endangered owing to their vulnerability to deforestation and degradation, including fire and logging.

Recommended action

In the article, the researchers recommend action to conserve and restore biomes in line with the carbon emission reduction effort to which Brazil is committed, including measures to combat illegal deforestation, legislation to protect secondary forests, stronger law enforcement and environmental inspection, large-scale initiatives to restore native vegetation, and economic incentives for landowners to conserve forest areas via payment for ecosystem services.

Incentives such as these will also be important to conserve forest areas that could legally be cleared as the law now stands. These areas are in properties where native vegetation accounts for a larger percentage than the mandatory “legal reserve”. According to the article, 38% of the total “surplus legal reserve” is in the Cerrado, 23% in the Caatinga, 13% in the Atlantic Rainforest biome, and 10% in the Amazon.

National legislation is needed to increase protection of secondary forests outside legal reserve and permanent conservation areas so as to ensure that they contribute to carbon sequestration in the long term. “Existing laws and measures are insufficient to bring about change,” Aragão said. “The global climate is different. It won’t be possible to solve environmental problems, which are getting more severe because of climate change, if we rely solely on past thinking. We must pivot to future thinking.”

The Ministry for the Environment and Climate Change told Agência FAPESP via its press office that it has taken steps to achieve its commitment to “zero deforestation in all biomes by 2030”. The measures taken include União com Municípios (“Union with Municipalities”), a program launched in April as part of the Action Plan to Prevent and Control Deforestation in Legal Amazonia (PPCDAm), with BRL 785 million allocated to 70 priority municipalities, 48 of which have so far signed the adherence agreement; and tightening of the rules used by the National Monetary Council (CMN), such as banning farm loans to landowners whose permits under the Rural Environmental Register (CAR), designed to ensure compliance with the Forest Code, have been suspended or who have broken the law on Indigenous Territories, conservation units and undesignated public forests.

In addition, the ministry highlighted resumption of the Amazon Fund, with new contracts worth BRL 1.4 billion and further donations set to reach BRL 3.1 billion. An anti-deforestation action plan similar to PPCDAm has been launched for the Cerrado. On restoration, it cited the National Plan for Restoration of Native Vegetation, which aims to extend and strengthen public policy, financial incentives, markets, restoration and rehabilitation technologies, and agricultural best practices, and will be updated this year.

Next steps

According to Dutra, next steps for the researchers will focus on the economic losses caused by deforestation, further developing the data used in the latest study.

“Estimating the cost of the impact is highly valuable in our view, especially to show it‘s much cheaper to prevent than to reconstruct. Brazil does quite a lot in terms of responses to extreme events and natural disasters but needs to invest in prevention,” Aragão said.

For Anderson, more and better dialogue is needed among federal, state and municipal institutions, the third sector, and local communities. Penalties for inaction or failure to implement plans are another requirement. “Our capacity for dialogue is very limited,” he said. “It’s hindered by political distortions and falls well short of what can be done technically to make faster progress.”

FAPESP supported the study via six projects (20/15230-5; 20/08916-8; 22/11698-8; 19/25701-8; 23/03206-0; and 20/16457-3).

About São Paulo Research Foundation (FAPESP)

The São Paulo Research Foundation (FAPESP) is a public institution with the mission of supporting scientific research in all fields of knowledge by awarding scholarships, fellowships and grants to investigators linked with higher education and research institutions in the State of São Paulo, Brazil. FAPESP is aware that the very best research can only be done by working with the best researchers internationally. Therefore, it has established partnerships with funding agencies, higher education, private companies, and research organizations in other countries known for the quality of their research and has been encouraging scientists funded by its grants to further develop their international collaboration. You can learn more about FAPESP at www.fapesp.br/en and visit FAPESP news agency at www.agencia.fapesp.br/en to keep updated with the latest scientific breakthroughs FAPESP helps achieve through its many programs, awards and research centers. You may also subscribe to FAPESP news agency at http://agencia.fapesp.br/subscribe.

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Journal

Perspectives in Ecology and Conservation

DOI

10.1016/j.pecon.2024.04.004 

Article Title

Challenges for reducing carbon emissions from Land-Use and Land Cover Change in Brazil

 ZOONOSIS

Pigs may be transmission route of rat hepatitis E to humans

Study shows viral strain infects, circulates among swine

Ohio State University

COLUMBUS, Ohio – New research suggests that pigs may function as a transmission vehicle for a strain of the hepatitis E virus (HEV) common in rats that has recently been found to infect humans.

The Rocahepevirus ratti strain is called “rat HEV” because rats are the primary reservoir of the virus. Since the first human case was reported in a person with a suppressed immune system in Hong Kong in 2018, at least 20 total human cases have been reported – including in people with normal immune function.

People infected with rat HEV did not report exposure to rats, leaving the cause of infection undefined. The suspected cause during other human HEV infections, in many cases, is consumption of raw pork – making it a potential route for rat HEV as well.

Researchers at The Ohio State University found that a strain of rat HEV isolated from humans could infect pigs and was transmitted among co-housed animals in farm-like conditions. Rats are common pests in swine barns – suggesting that the pork production industry may be a setting in which rat HEV could make its way to humans.

“We always want to know which viruses might be up and coming, so we need to know the genetics behind this virus in the unlikely event something happens in the United States that would enable rat HEV to expand,” said senior author Scott Kenney, an associate professor of veterinary preventive medicine at Ohio State based in the Center for Food Animal Health at the College of Food, Agricultural, and Environmental Sciences’ Wooster campus. 

The study was published recently in PNAS Nexus.

Hepatitis E is the leading cause of the acute viral liver infection in humans worldwide, mostly in developing regions where sanitation is poor. The virus is also endemic in pigs in the United States – though it is present mostly in liver rather than muscle, and is killed when the meat is cooked. 

Past studies testing the cross-species infectiousness of rat HEV showed the strain used in experiments did not infect non-human primates.

“It dropped off the radar for six or seven years because it was thought not to be a human pathogen. And now it’s infecting humans, so we need to figure out why,” Kenney said.

One strain linked to human disease is known as LCK-3110. First author Kush Yadav, who completed this work as a PhD student in the Center for Food Animal Health, used the viral genomic sequence to construct an infectious clone of LCK-3110.

The team first showed the cloned virus could replicate in multiple types of human and mammal cell cultures and in pigs. Researchers then injected pigs with an infectious solution containing the LCK-3110 strain or another HEV strain present in pigs in the U.S., as well as saline as a control condition.

Viral particles in the blood and feces were detected one week later in both groups receiving HEV strains, but levels were higher in pigs infected with rat HEV. Two weeks later, co-housed pigs that received no inoculations also began to shed rat HEV virus in their feces – an indication the virus had spread through the fecal-oral route.

Though infected pigs’ organs and bodily fluids were also positive for viral RNA, the animals did not show signs of feeling sick. Previous research suggests rats don’t have clinical symptoms, either.

Even so, the rat HEV virus was detected in cerebrospinal fluid of infected pigs – a finding that aligns with growing concern that various strains of HEV that infect humans can harm the brain. One human death linked to rat HEV was caused by meningoencephalitis.

“HEV is gaining importance for neurological disorders, and a lot of the research now points toward how neuropathology is caused by the hepatitis E virus,” Yadav said. “And even though we have a small number of known human cases, a high percentage of them are immunosuppressed. That means transplant recipients in the United States could be at risk of infection by general HEV as well as rat HEV.

“Research could now focus on whether pork liver products contain rat HEV and explore food safety procedures to block the disease.”

Yadav is now a postdoctoral researcher in the Virginia-Maryland College of Veterinary Medicine at Virginia Tech. Co-authors of the study, all from Ohio State, were Patricia Boley, Carolyn Lee, Saroj Khatiwada, Kwonil Jung, Thamonpan Laocharoensuk, Jake Hofstetter, Ronna Wood and Juliette Hanson.

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Contacts:

Scott Kenney, Kenney.157@osu.edu
Kush Yadav, Yadav.94@osu.edu

Written by Emily Caldwell, Caldwell.151@osu.edu; 614-292-8152

 

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Journal

PNAS Nexus

DOI

10.1093/pnasnexus/pgae259 

Article Title

Rat hepatitis E virus cross-species infection and transmission in pigs

 

Review shows bird flu control strategies ‘not working’

Gaps in data highlight potential for silent spread

The Pirbright Institute

 

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A chicken 

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Credit: The Pirbright Institute

A review of sustained mammal-to-mammal bird flu transmission in diverse species, led by The Pirbright Institute, shows global control strategies are not working.

Writing in Nature, researchers analysed whether outbreaks in European fur farms, South American marine mammals and United States dairy cattle raise questions about whether humans are next. Led by zoonotic influenza specialist Dr Thomas Peacock, the scientists evaluated how recent changes in the ecology and molecular evolution of H5N1 in wild and domestic birds increase opportunities for spillover to mammals.

They also weighed various evolutionary pathways that could turn the global H5N1 influenza panzootic into a human pandemic virus.

“Influenza A viruses (IAV) have caused more documented global pandemics in human history than any other pathogen. Historically, swine are considered optimal intermediary hosts that help avian influenza viruses adapt to mammals before jumping to humans,” said Dr Peacock, who investigates the drivers of the current H5N1 avian influenza panzootic. “However, the altered ecology of H5N1 has opened the door to new evolutionary pathways.”

The review highlights potential gaps in control mechanisms, including a reluctance to engage with modern vaccine and surveillance technologies and a dearth of data collection around the transmission of H5N1 between cows and to humans on US dairy farms.

Whilst previous generations of US cattle producers had eradicated foot-and-mouth disease by rapidly sharing epidemiological data, the authors say months of missing data is leaving researchers, veterinarians, and policy makers in the dark.

“H5N1 is a reportable disease in poultry, but not mammals, in the US. The US Department of Agriculture requires H5N1 testing only in lactating cattle prior to interstate movement,” said Dr Peacock.

Current practices for H5N1 testing in wildlife focus on carcasses, not monitoring animals whilst alive, the paper notes, providing opportunities for variants of H5N1 to spread silently undetected.

“What keeps scientists up at night is the possibility of unseen chains of transmission silently spreading through farm worker barracks, swine barns, or developing countries, evolving under the radar because testing criteria are narrow, government authorities are feared, or resources are thin.”

An evolutionary process of “genomic reassortment” in viruses with segmented genomes is driving the global panzootic outbreak. When two or more viruses co-infect a single host, they can swap entire segments during genome replication to create novel hybrids.

The reassortment between H5N8 and low pathogenicity avian influenza (LPAI) viruses that generated the panzootic H5N1 virus in the Americas is believed to have occurred in Europe or central Asia around 2020, infecting South American marine mammals and US dairy cattle.

The writers say the prospect of H5N1 becoming continually present in Europe and the Americas is a turning point for High Pathogenicity Avian Influenza (HPAI).

“New control strategies are needed, including vaccination. Influenza vaccines are licensed for poultry that reduce disease burden, but do not prevent infection and have varying degrees of success.”

Stocks of H5 vaccine that are antigenically related to circulating viruses are available and could be produced at scale using mRNA platforms if H5N1 begins spreading in humans, the authors note.

“The severity of a future H5N1 pandemic remains unclear. Recent human infections with H5N1 have a substantially lower case fatality rate compared to prior H5N1 outbreak in Asia, where half of people with reported infections died. The lack of severity in US cases may be due to infection through the eye, rather than through viral pneumonia in the lung.”

Older people appear to have partial immunity to H5N1 due to childhood exposure, whereas younger people born since the 1968 H3N2 pandemic may be more susceptible to severe disease in a H5N1 pandemic.

Dr Peacock’s work is funded by UKRI Biotechnology and Biological Sciences Research Council (BBSRC) via the Pirbright Institute’s Strategic Programme Grants (ISPGs)  and the UK Medical Research Council / Department for Environment, Food and Rural Affairs FluTrailMap One Health consortium, and the BBSRC/DEFRA ‘FluTrailMap’ consortium.

Read the Paper: https://www.nature.com/articles/s41586-024-08054-z

DOI: 10.1038/s41586-024-08054-z

 

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Journal

Nature

DOI

10.1038/s41586-024-08054-z 

Method of Research

Literature review

Article Title

The global H5N1 panzootic in mammals

Article Publication Date

24-Sep-2024

 

Mesoamerican oak tree species in urgent need of conservation, according to milestone report by The Morton Arboretum

The Morton Arboretum

 

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Encino arroyero (Quercus brandegeei) (endangered) in Baja California Sur, Mexico

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Credit: The Morton Arboretum

LISLE, Ill. (Sept. 24, 2024)— Over a third of threatened or understudied oak tree species in Mesoamerica are not held in managed botanical collections anywhere in the world, and for many species, protection of their native habitats is lacking.

These are among the findings in a new Conservation Gap Analysis of Native Mesoamerican Oaks, published in English and Spanish, which was conducted by researchers at The Morton Arboretum. Researchers stress in the report being released during National Hispanic Heritage Month in the U.S. that it's critically important to conserve these trees now before land-use conversion, climate change and other threats further alter their natural environments. Mesoamerica is the region extending from the U.S.-Mexico border through Panama.

Oaks are valuable keystone species that perform critical ecosystem functions and provide food and habitat for myriad animals.

“Mesoamerica is a global hotspot for oak biodiversity,” said report lead author Kate Good, the Arboretum’s global tree conservation research program manager. “In the face of climate change and habitat degradation, there is an urgent need to increase the number of Mesoamerican oaks in collections within their native country to help prevent further biodiversity loss.”

As of 2022, 22 species, or 37%, are not held in managed botanical collections anywhere in the world.

“We hope this report can help identify potential areas for collaboration and set conservation priorities, both in native habitats and managed botanical collections," Good said.

The report focuses on 59 species in the region on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species assessed as either threatened or Data Deficient. The IUCN Red List is the globally recognized and standardized system for assessing the extinction risk of the world’s plant, animal and fungal species.

Climate change was identified as a threat for all 59 threatened or Data Deficient Mesoamerican oak species. Additionally, agriculture and residential or commercial development represented threats to 72% and 69% of the species, respectively.

Overall, the report indicates that 85% of the analyzed oak species are projected to see a decrease in the areas they are most commonly found under climate conditions predicted for the years 2061-2080. A decrease in a species’ preferred “life-zone area” does not necessarily mean it will no longer survive in the new environment, according to the report. However, it does mean conservation activities are strongly needed to prevent potential biodiversity loss. Education, outreach, research and propagation or breeding programs were the most commonly cited priorities in the report for future conservation efforts.

The analysis also showed 16, or approximately one quarter, of the target species have less than 10% of their native range in protected areas. Among the 59 oaks analyzed for the report were the critically endangered Muller oak (Quercus mulleri), known to live in only two locations in Mexico; endangered Encino arroyero (Quercus brandegeei) native to southern Baja California Sur, Mexico; vulnerable oak species Quercus gulielmi-treleasei native to Costa Rica, Mexico and Panama; and data-deficient white oak Quercus deliquescens from Chihuahua, Mexico, to name a few.

“For many species, little is known regarding population size, distribution or threats,” said report co-author Silvia Alvarez-Clare, Ph.D., director of the Arboretum’s Global Tree Conservation Program. “This analysis helps to fill those knowledge gaps and is a crucial step toward facilitating partnerships and spurring conservation action to help protect threatened Mesoamerican oaks before time runs out.”

The report findings will be highlighted during the Arboretum’s National Hispanic Heritage Month programming. A free presentation about conserving threatened cloud forests and some of the most important oak species from the analysis will be held Sept. 26 at the Arboretum with guest speaker Tarin Toledo Aceves, Ph.D. She is a researcher from Instituto de Ecología A.C. in Veracruz, Mexico and a collaborator with the Arboretum’s Global Tree Conservation Program.

Additionally, the Arboretum will offer Herbarium tours showcasing Mesoamerican specimens noted in the gap analysis during the two-day Celebración de los Árboles (Celebration of Trees) cultural festival, Sept. 28 and 29.

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About The Morton Arboretum 
The Morton Arboretum is a globally recognized leader in tree research and education. Its 1,700 acre site cares for 106,714 specimens representing 4,067 different kinds of plants. The Arboretum’s Center for Tree Science, Global Tree Conservation Program, Chicago Region Trees Initiative, and Center for Species Survival: Trees are contributing scientific knowledge and technical experience to secure the future of trees locally, nationally, and worldwide. Information about the Arboretum’s scientific work and how it contributes to a greener, healthier world where people and trees thrive together can be found at mortonarb.org.

 

Nursing shortages can be deadly

Oxford University Press USA

A new paper in the British Journal of Surgery, published by Oxford University Press, shows that nursing shortages result in longer hospital stays and worse patient outcomes, including higher mortality.

Doctors perform over 300 million surgeries each year worldwide. Observers have expressed concern about the quality of care for adult patients undergoing surgery and the rising cost of avoidable complications, extended hospitalizations, and readmissions. Some 55% of surgical site infections are preventable.

Until now safety interventions to address this have focused mostly on implementing checklists, staff training and improving teamwork. But staff shortages alone may be an important reason for infections and other adverse outcomes after surgery. Nurses play an important role in keeping surgical patients safe and healthy. Understaffing by both registered nurses and nurse assistants is associated with increased risks of a range of adverse events.

One recent review of 44 studies found that higher nurse staffing levels were associated with lower 30-day mortality among surgical patients. However, most studies have focused on staffing at the hospital level, rather than in actual surgical wards. In this new paper researchers from the University of Southampton, using surgical patient and staffing data from 213,910 hospital admissions from four medical institutions in the English National Health Service, explored outcomes between April 2015 and February 2020.

In situations where staffing levels were below the mean for the ward, researchers found that such understaffing increases the relative risk of readmission by 2.3% for nursing shortages (and by 1.4% for nursing assistant shortages). The study indicated that nursing shortages were associated with 4.8% increases in deep vein thrombosis, 5.7% increases in pneumonia, and 6.4% increases in pressure ulcers.

The relative risk of mortality increased by 9.2% with each day of low registered nurse staffing and by 10.3% for each day of low nursing assistant staffing.

“The safety of patients undergoing surgery is paramount and there is rightly a considerable emphasis on appropriate systems, policies, and procedures,” said the paper’s lead author, Paul Meredith. “This research is a timely reminder that workload is also a major driver of risk and that risks to surgical patients persist beyond the immediate operative period. Adequate nurse staffing on wards is vital to ensure the safety of patients undergoing and recovering from surgery.”

The paper, “Associations between outcomes for surgical admissions and nurse staffing – a longitudinal study using routine data from English Acute Hospitals,” is available (on September 24th ) at https://academic.oup.com/bjs/article-lookup/doi/10.1093/bjs/znae215.

Direct correspondence to: 
Paul Meredith
Senior Research Fellow, School of Health Sciences
University of Southampton,
Southampton, SO17 1BJ, UNITED KINGDOM
p.f.meredith@soton.ac.uk

To request a copy of the study, please contact:
Daniel Luzer 
daniel.luzer@oup.com

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Journal

BJS (British Journal of Surgery)

DOI

10.1093/bjs/znae215 

Method of Research

Data/statistical analysis

Subject of Research

People

Article Title

Associations between outcomes for surgical admissions and nurse staffing – a longitudinal study using routine data from English Acute Hospitals

Article Publication Date

24-Sep-2024

 

The environmental impacts of genetically modified crops

University of Toronto

Genetically modified (GM) crops are widely used around the world, but their effects on the environment need to be explored more.

New research, published in Science on August 30, 2024, takes a look at common genetic modifications in four crops: soybean, corn, cotton, and canola. Although GM crops can produce more yield and profits, it can lead to changes in agricultural practices that could inadvertently impact the environment. For example, farmers may increase pesticide use as crops become more resistant to herbicides or insect pests.  

“Increasing land productivity in the form of greater crop yields can make agricultural land more profitable overall, which can encourage agricultural expansion,” explains co-author Eduardo Souza-Rodrigues, an associate professor and associate chair with the Department of Economics at University of Toronto Mississauga. “However, increased supply may then reduce crop prices, which decreases the conversion of additional land to agriculture elsewhere. These changes have the potential to cause deforestation, pollution, greenhouse gas emissions and impacts to human health, and biodiversity.”

“Although we have made progress in understanding the impact GM crops have on our environment, there are much more uncertainties that need to be studied to support good farming practices that are better for the environment,” Souza-Rodrigues continued.

The study concludes more research is needed to understand the long-term effects of GM crops on large-scale agricultural practices and resistant pests. Gathering more detailed environmental data, especially about wildlife, will better measure their impacts and support farming practices that promote sustainable agriculture.
 

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Journal

Science

DOI

10.1126/science.ado9340 

Article Title

Environmental impacts of genetically modified crops

Study: Good nutrition boosts honey bee resilience against pesticides, viruses

University of Illinois at Urbana-Champaign, News Bureau

 

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llinois entomology professor Adam Dolezal, right, and graduate student Edward Hsieh found that pollen from natural sources enhances honey bee resilience when the bees are exposed to agricultural chemicals and infected with Israeli Acute Paralysis Virus.

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Credit: Photo by Michelle Hassel

CHAMPAIGN, Ill. — In a new study, researchers at the University of Illinois Urbana-Champaign tackled a thorny problem: How do nutritional stress, viral infections and exposure to pesticides together influence honey bee survival? By looking at all three stressors together, the scientists found that good nutrition enhances honey bee resilience against the other threats.

Their findings are detailed in the journal Science of the Total Environment.

“Multiple stressors are often bad for survival,” said graduate student Edward Hsieh, who led the research with U. of I. entomology professor Adam Dolezal. “However, it is always context-dependent, and you have to be aware of all these factors when you’re trying to make broad statements about how interactive effects affect honey bees.”

Most studies focus on only one or two factors at a time, Hsieh said. They will explore the interplay of poor nutrition and pesticide exposures, for example, or pesticides and viral infections. But no previous studies have looked at how all three factors contribute to honey bee declines — probably because doing so is quite challenging.

Even understanding how bees respond to all the agricultural chemicals they encounter is a complicated task, Dolezal said.

“Some insecticides will work better against some insects than others, but they tend to be more lethal than fungicides or herbicides,” he said. “Some fungicides, however, are known to make insecticides more toxic to insects.”

For the new study, the team looked at pollen collected by honey bees visiting small patches of restored prairie bordering agricultural fields in Iowa. The researchers used the maximum insecticide and fungicide levels detected in bee-collected pollen grains as their guide to likely chemical exposures in the wild.

In a series of experiments, Hsieh exposed groups of caged honey bees to different dietary, viral and/or chemical treatments. The bees were fed either artificial or natural pollen. The agricultural pesticides included chlorpyrifos, an organophosphate; lambda-cyhalothrin, a pyrethroid; or thiamethoxam, a neonicotinoid. Hsieh also infected some of the caged bees with the Israeli Acute Paralysis Virus, one of several viruses known to contribute to the collapse of honey bee colonies around the world.

The experiments yielded some obvious and some unexpected results, Dolezal said.

“What we found was that with the artificial pollen, if bees are exposed to the virus, a lot of them die. And if you expose them to the virus and pesticide at the same time, even more of them die,” he said. “However, if you do the exact same experiment but you give them better nutrition, you get a very different outcome.”

On the natural pollen diet, bees exposed to the virus still experienced higher mortality, the researchers found. But fewer bees died when they were also exposed to a mixture of chlorpyrifos and a fungicide.

“Bees have this inherent ability to deal with stress, and so if you give them a little bit of stress, like a low-level exposure to a pesticide, it may help them deal with a bigger stress from a pathogen like the virus,” Dolezal said. “However, it only works if they have the nutritional resources to do it.”

The researchers warned this doesn’t mean that chemical exposures don’t matter.

“Different pesticides have different molecular targets and do different things,” Dolezal said. “It’s not okay if bees get exposed to a little bit of any pesticide. It depends on the chemical.”

The findings offer some reassurance that providing high-quality prairie habitat near agricultural sites does not create an “ecological trap,” attracting bees to the flowers only to kill them with agricultural chemicals.

“The takeaway from this study is that bees are quite resilient even to the interaction of pesticides and viruses if they have really good nutrition,” Dolezal said. “However, we don’t want people to conclude that pesticides are not a big deal for the bees.”

Pesticides, alone or in combination with viruses, are in most cases detrimental to bees.

“But it is gratifying to know that providing high-quality habitat can at least increase their resilience to these stressors,” Hsieh said.

The Foundation for Food and Agriculture Research and the North American Pollinator Protection Campaign supported this research. Dolezal also is an affiliate of the Carl R. Woese Institute for Genomic Biology at the U. of I.

Ecologists worried that creating narrow strips of pollinator habitat abutting agricultural fields might serve as an “ecological trap” for bees, drawing them in to forage on the flowers only to kill them with pesticides. A new study finds that high-quality floral resources boost honey bee resilience against pesticide exposures and infection with a deadly virus.

Credit

Photos by Iowa State University, left, and Lynn Betts, right

Honey bees do best when they have access to a variety of natural pollens.

Credit

Photo by Michelle Hasse

 

Editor’s note:  

The paper “Nutrition, pesticide exposure and virus infection interact to produce context-dependent effects in honey bees (Apis mellifera)” is available online.

DOI: 10.1016/j.scitotenv.2024.175125

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Journal

Science of The Total Environment

DOI

10.1016/j.scitotenv.2024.175125 

Method of Research

Experimental study

Subject of Research

Animals

Article Title

Nutrition, pesticide exposure and virus infection interact to produce context-dependent effects in honey bees (Apis mellifera)

Article Publication Date

30-Jul-2024

COI Statement

The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Adam G. Dolezal reports financial support was provided by Foundation for Food and Agriculture Research. Edward M. Hsieh reports financial support was provided by North American Pollinator Protection Campaign.