Hypodematium crenatum crenatum

Growth of the Amazon rainforest in our increasingly carbon-rich atmosphere could be significantly limited by a lack of phosphorus in the soil, according to a new study led by Brazil’s <a href="https://www.gov.br/inpa/pt-br">National Institute of Amazonian Research</a> (INPA) and the <a href="https://www.exeter.ac.uk/">University of Exeter</a>.



Although higher concentrations of <a href="https://www.earth.com/news/carbon-dioxide-has-a-minimal-impact-on-tropical-vegetation/">carbon dioxide</a> cause plants to grow faster to store more of this greenhouse gas – and thus help mitigating climate change – plants also need nutrients such as nitrogen and phosphorus to grow. As a consequence, reduced availability of such nutrients could limit the Amazon rainforest’s ability to increase its productivity, or growth rate, as CO2 rises, and make it less resilient to climate change.



“Our results question the potential for current high rates of carbon uptake in Amazonia to be maintained,” said study lead author Hellen Fernanda Viana Cunha, a doctoral student in Tropical Forest Science at INPA. “About 60 percent of the Amazon basin is on old soils with low phosphorus content, but the role of phosphorus in controlling productivity was unclear because most fertilization experiments in other parts of the world have been in more phosphorus-rich systems.”



To examine the effects of adding phosphorus, nitrogen, and other key nutrients in an old-growth, low-phosphorus area of the rainforest, the researchers conducted a longitudinal empirical study - the&nbsp;<a href="https://amazonfertilisationexperiment.wordpress.com/">Amazon Fertilisation Experiment</a>&nbsp;(AFEX) – and found that only phosphorus led to increased productivity in the first two years of the experiment. “Having such rapid and strong responses to phosphorus, both above and below ground, is an indication that the whole system was functioning under severe phosphorous limitation,” Cunha explained.



While other nutrients such as nitrogen can be absorbed from the atmosphere by micro-organisms associated with certain soils and plants, phosphorus is not available as an atmospheric gas. Thus, once it becomes depleted, there are little opportunities for phosphorus levels to increase.&nbsp;



The experiments revealed that two years with extra phosphorus led to a significant increase in fine root growth (29 percent) and canopy productivity (19 percent), but not in stem growth. According to Cunha, this may be because roots and leaves require more phosphorus than stem. However, since stem growth is also a much slower process, long-term monitoring is necessary to determine whether stem wood productivity will later on increase.



This study has major implications not only for the rainforest’s carbon storage capacity, but also for its resilience to climate change. “To cope with and recover from increased threats such as droughts, we need the forest to be growing better than it used to,” said&nbsp;Iain Hartley, a professor of Geography at Exeter.



“CO2 fertilization could increase the forest’s resilience, but our findings suggest phosphorus availability will limit that effect – and therefore the risks caused by climate change become increasingly important. In short, parts of the rainforest growing in low-fertility soils may be more vulnerable than is currently recognized,” he concluded.



The study is published in the journal <a href="http://dx.doi.org/10.1038/s41586-022-05085-2">Nature</a>.



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By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer&nbsp;&nbsp;

Lack of phosphorus will limit growth of the Amazon rainforest

Growth of the Amazon rainforest in our increasingly carbon-rich atmosphere...

Dry,Drought,Stricken,Farm,Corn,Field,Dirt

Scientists have identified an “exquisite” natural mechanism that helps plants limit their <a href="https://www.earth.com/news/transforming-sunlight-and-water-into-renewable-energy/">water</a> loss with little effect on carbon dioxide (CO2) intake. The study, led by <a href="https://www.anu.edu.au/">Australian National University</a> (ANU), touches on an essential process for photosynthesis, plant growth and crop yield.&nbsp;



The discovery is expected to help agricultural scientists and plant breeders develop more water-efficient crops that are resilient to extreme weather events such as drought.&nbsp;&nbsp;



“Plants continuously lose water through pores in the ‘skin’ of their leaves. These same pores allow CO2 to enter the leaves and are critical to their survival,” said study co-author Dr Marquez.&nbsp; “For every unit of CO2 gained, plants typically lose hundreds of units of water. This is why plants require a lot of water in order to grow and survive."



“The mechanism we have demonstrated is activated when the environment is dry, such as on a hot summer day, to allow the plant to reduce water loss with little effect on CO2 uptake."



The researchers believe this water preserving mechanism can be manipulated to breed more water-efficient crops.&nbsp;&nbsp;



According to study lead author Dr. Chin&nbsp; Wong, the ANU team’s findings are a “dream discovery” from a scientific and agricultural perspective. The agricultural industry has long waited for a way to deliver crops that use water efficiently.&nbsp;



Although the researchers have confirmed there is a system in place that is working to limit the amount of water being lost from the leaf, they still do not know what’s causing it.&nbsp;&nbsp;&nbsp;



“Our main target now is to identify the structures inside the plant that allow this control. We think that water conduits, called aquaporins, located in the cell membranes are responsible,” said Dr. Marquez.&nbsp;



Once this can be confirmed, the team will continue to explore how these systems can become an asset for the agriculture industry.



Dr. Wong first alluded to this water preserving mechanism 14 years ago, but the research team has only now been able to officially confirm its existence thanks to years of experimentation and corroboration of their results.&nbsp;&nbsp;



The study is published in the journal <a href="https://www.nature.com/nplants/">Nature Plants</a>.&nbsp;



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By <a href="mailto:katherinebucko@gmail.com">Katherine Bucko</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

"Exquisite" mechanism will help plants survive drought

Scientists have identified an “exquisite” natural mechanism that helps plants...

Synthetic cannabinoids are “designer drugs” that mimic the effects of cannabis and are popularly used as an alternative to natural cannabis. Typically synthetic cannabinoids are sprayed onto plant leaves and then smoked; they are often marketed as “herbal smoking blends” and sold under such common names as K2, spice or synthetic <a href="https://www.earth.com/news/legalization-of-marijuana-linked-to-rise-in-traffic-crashes/">marijuana</a>. In fact, they are not cannabis at all, but have been designed to bind to the same brain receptors that are responsible for the psychoactive effects of tetrahydrocannabinol (THC) in cannabis.



A new study, led by researchers from <a href="https://wsu.edu/">Washington State University</a>, has now investigated whether the use of synthetic cannabinoid drugs has changed in recent years and whether this is linked to the status of cannabis legalization in different U.S. states. They hypothesized that in states with more liberal cannabis policies which allow access to THC-containing products for recreational and other purposes, there would be a decrease in the use of synthetic cannabinoid drugs.&nbsp;



It is not easy to monitor the use of these drugs because they are often designed to be undetectable in urine. In addition, their chemical structure is constantly being changed by illicit manufacturers as new versions are developed, so standard drug tests commonly don’t identify them. Instead, the researchers used data from the National Poison Data System (NPDS), a data management system owned by the American Association of Poison Control Centers (AAPCC). Cases of poisoning in people who take synthetic cannabinoids and end up needing medical care, or who die, are reported to the NPDS by clinicians and the general public, via regional poison control centers.&nbsp;



This approach provided the researchers with comprehensive coverage of poisoning due to synthetic cannabinoids in the U.S., and they were then able to investigate any links between cases of poisoning and the type of legislation pertaining to cannabis use in each state.&nbsp;



They analyzed data on poisoning for the years 2016 to 2019 and looked only at states that had stable policies concerning cannabis use during those years. In this connection, they placed states in one of three categories: those that had permissive legislation, like Washington State, allowing both medical and recreational adult use of cannabis; those that allow medical use of cannabis only, like Hawaii; and those that had restrictive legislation, like Idaho, where nearly all cannabis use is prohibited.&nbsp;&nbsp;



The researchers found that.during the years 2016 to 1019, there were 7,600 calls that reported poisoning due to synthetic cannabinoid use - about 65 percent of which required medical attention. There were also 61 deaths. The results of the analysis, published in the <a href="https://www.longdom.org/clinical-toxicology.html">Journal of Clinical Toxicology</a>, showed that cases of synthetic-related poisoning decreased overall during this time period but, while there were 13 percent fewer cases in states where only medical use of cannabis was allowed, there was a much more significant decrease (37 percent) in permissive states, which allow recreational or “adult use” of cannabis.&nbsp;



“This study shows some potential public health benefits to the legalization and regulation of adult use of cannabis,” said study lead author Tracy Klein, a WSU associate professor of nursing. “Based on both past research and this current study, it's evident that users who have a choice to use a less toxic product would potentially do so.”



People who use synthetic cannabinoids actually report a preference for natural cannabis products, due in part to their lower negative effect profile including less hangover effects, less paranoia and more ability to function. The synthetic substances bind up to 100 times more readily with the brain receptors and lack any mediating constituents of whole plant cannabis, such as cannabidiol (CB). As a result, synthetic cannabinoids have a high toxicity and can lead to severe impairment, and even death.



An earlier study&nbsp;found that poison control calls related to natural cannabis use also increased between 2017 and 2019 across the U.S. but were driven mainly by manufactured products, such as plant-based vaping materials and edibles, which can contain high levels of THC. In contrast, poison control calls for whole plant cannabis declined during the same time period.



More research is needed to understand the use of these drugs better and the differences between them, Klein said. She pointed out that the study’s data set does not contain the rising popularity of synthetically derived Delta-8, marketed as a less strong form of Delta-9, which is the psychoactive cannabinoid found in naturally produced plant products.



“We know that there are many cannabinoids being developed and on the market – and the regulators are struggling to catch up,” said Professor Klein, who is also the assistant director of WSU’s Center for Cannabis Policy, Research and Outreach.



The current study likely underestimates the use of these drugs, the authors note, because the drugs are difficult to detect.



“You can’t easily test for illicit cannabinoids. A lot of times, we only find out if a patient has been using them because they’re hospitalized or because they’re dead,” said Professor Klein.



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By <a href="mailto:bosman@truewan.co.za">Alison Bosman</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Cannabis legalization reduces designer drug poisonings

Synthetic cannabinoids are “designer drugs” that mimic the effects of...

In a series of studies led by the <a href="http://www.wne.edu/">Western New England University</a>, scientists found that grape consumption has a remarkable impact on health and lifespan. According to the experts, adding just under two cups of <a href="https://www.earth.com/news/red-wine-grapes-have-unexpected-gut-health-benefits/">grapes</a> per day to a high-fat diet can have astonishing health benefits, yielding reductions in fatty liver, boosting levels of antioxidant genes, and significantly increasing longevity. Although the studies have been performed on mice, their results could be reliably translatable to human health-related issues.



The first study, published in the journal <a href="https://www.mdpi.com/2304-8158/11/13/1984">Foods</a>,&nbsp;focused on the potential of dietary grape consumption to modulate the adverse effects caused by high-fat diets. The analysis revealed that, in mice on a high-fat diet, grape powder consumption led to a significant modulation of hepatic gene expression, successfully prevented oxidative damage, ameliorated non-alcoholic fatty liver disease, and increased longevity.



In a second study published in the journal <a href="https://www.mdpi.com/2076-3921/11/2/414">Antioxidants</a>, the researchers found that grape consumption altered gene expression in the brain and had positive effects on behavioral and cognitive structures that were impaired by high-fat diets.&nbsp;



Finally, a third study published in the journal <a href="https://pubs.rsc.org/en/content/articlehtml/2022/fo/d2fo00961g">Food &amp; Function</a> has shown that in addition to changes in genetic expression, grape consumption can boost metabolism by reprogramming gut microbiota activity. This reduces the hepatic oxidative stress of high-fat diets, and increases the efficiency of glucose utilization by the liver for energy production.



“We have all heard the saying ‘you are what you eat’ which is obviously true since we all start out as a fetus and end up being an adult by eating food,” said John Pezzuto, a professor of Pharmacy and Health Sciences at the Western New England University and senior author of the studies. “But these studies add an entirely new dimension to that old saying. Not only is food converted to our body parts, but as shown by our work with dietary grapes, it actually changes our genetic expression. That is truly remarkable.”



“Many people think about taking dietary supplements that boast high antioxidant activity. In actual fact, though, you cannot consume enough of an antioxidant to make a big difference. But if you change the level of antioxidant gene expression, as we observed with grapes added to the diet, the result is a catalytic response that can make a real difference,” he concluded.



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By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer&nbsp;&nbsp;

Grapes have astonishing health benefits

In a series of studies led by the Western New...

Grasslands – which account for almost 40 percent of land-based <a href="https://www.earth.com/news/how-can-earths-ecosystems-adapt-to-climate-change/">ecosystems</a> – provide habitat for a vast diversity of plants and animals, and contribute to the livelihood of over one billion of people all over the world. Moreover, they provide significant carbon sequestration and biodiversity benefits, and can be more resilient to a rapidly changing climate than forests. Unfortunately, during the past few centuries, ancient grasslands worldwide have been largely converted into farmland, used to grow trees, or been replaced by urban areas as citied expanded.&nbsp;



According to a new study led by the <a href="https://colorado.edu/">University of Colorado Boulder</a>, while the destruction of these pristine grasslands can occur very quickly, the complete recovery of grassland biodiversity and essential ecosystem functions occurs much slower, if at all. These findings contradict prior scientific assumptions that grasslands’ ecological development is quick and their recovery is rapid, posing new challenges to their successful restoration.



“Old growth grasslands have a unique suite of characteristics that develop over a really long time. Recovering grasslands do not have the same species or the same characteristics as they did prior to soil tilling or tree planting, and they take centuries to redevelop,” said study senior author Katharine Suding, a plant community ecologist at CU Boulder. 



“If you plant trees in an older grassland or till it for agriculture, you will probably never get many of the unique diversity and belowground characteristics back. It is irreversible. It’s an important reminder that we need to conserve the ancient grasslands that are still intact.”&nbsp;



Compared to newer, younger grasslands, old growth grasslands are unique in their underground structure and biodiversity and need a long time to be restored. “We should think of restoration as more of guiding a trajectory. Some species don’t come in right at the start, and the disturbance that maintains the grassland needs time to grow and be tweaked as these species get established and the soil develops. These processes take time,” explained Professor Suding.&nbsp;



While planting trees has become a popular “natural solution” worldwide to remove carbon from the atmosphere in order to mitigate climate change, many scientists warn than planting trees on natural grassland may create more problems than it solves. “We would lose a huge element of the biodiversity on Earth if we planted trees in old growth grasslands. I think we need to be a little bit more careful about what’s best for the globe, in terms of where to restore what,” warned Suding.



“Viewing grassland restoration as long-term assembly toward old-growth endpoints, with appreciation of feedbacks and threshold shifts, will be crucial for recognizing when and how restoration can guide recovery of this globally important ecosystem,” the authors concluded.



The study is published in the journal <a href="http://dx.doi.org/10.1126/science.abo4605">Science</a>.



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By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer&nbsp;&nbsp;

Ancient grasslands take a long time to recover

Grasslands – which account for almost 40 percent of land-based...

Neotropical <a href="https://www.earth.com/video/coastal-wetlands-are-threatened-by-salt-water-intrusion/">wetlands</a> are among the most diverse and beautiful regions on Earth. They are home to exotic birds and rare mammals, including jaguars. A recent study from <a href="https://www.qmul.ac.uk/">Queen Mary University of London</a> highlights the urgent need to protect the biodiversity of Neotropical wetlands.&nbsp;



The large-scale study was conducted in Brazil and analyzed 72 wetland lakes in the Amazon, Araguaia, Pantanal, and Paraná regions. The researchers examined humans' impact on biodiversity. They also investigated how biodiversity levels affect multifunctionality, or the various functions an ecosystem provides.



"This is one of a few studies that demonstrate how human pressures compromise the functioning of wetlands through their negative impact on biodiversity," said study co-author Dr. Pavel Kratina. "To our knowledge, this work presents the first empirical evidence of a large-scale positive relationship between aquatic biodiversity across multiple organismal groups and multifunctionality of wetlands."



The team examined seven groups of aquatic species to demonstrate their influence on several ecosystem functions, including aquatic phosphorus and nitrogen availability, standing biomass, microorganism abundance, and underwater habitat complexity.



The experts used the Human Footprint (HFP) index to determine the level of human impact. The HFP index measures impacts from farmland, human density, light pollution, railways, roads, and navigable waterways.&nbsp;



The researchers found that human activities harm biodiversity, which is detrimental to the functioning of ecosystems. The Paraná wetland, located near a grossly populated area, was the most threatened.&nbsp;&nbsp;



"This high-resolution dataset revealed strong and consistent associations between the diversity of multiple groups of aquatic organisms and wetland multifunctionality," said Kratina. "These results underline the important role of species richness and functional diversity in driving functioning of Neotropical wetlands."



The experts also discovered that fish diversity can indicate how well an ecosystem functions. According to Dr. Kratina, the study shows that an increasing human footprint correlates with a decline in species richness and functional diversity.



"Human Footprint index has a large direct negative effect on multifunctionality, but HFP also had indirect negative effects on the multifunctionality, mediated by declining species richness," explained Dr. Kratina.



"Although these indirect negative effects of human pressure were driven by the decline in the diversity of most organismal groups, these effects were strongly mediated by fish diversity, because fish diversity is very important for functioning of wetlands."



The study is published in the journal <a href="https://www.nature.com/natecolevol/">Nature Ecology and Evolution</a>.



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By <a href="mailto:nire518@gmail.com">Erin Moody </a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Biodiversity loss weakens ecosystem functioning

Neotropical wetlands are among the most diverse and beautiful regions...

Scientists have long known that seagrass – the only underwater flowering plant on Earth – is not only vital for biodiversity, but also absorbs carbon dioxide, making it a valuable ally in the fight against climate change. However, by considering the value of seagrass beyond carbon removal in the context of the&nbsp;<a href="https://sdgs.un.org/goals">UN Sustainable Development goals</a>, a team of researchers led by <a href="https://www.swansea.ac.uk/">Swansea University</a> has found that, in fact, conserving and restoring seagrass meadows could actually contribute to achieving 16 out of the 17 goals.&nbsp;



“With the increasing realization of the planetary emergency that we face, there is growing interest in using seagrasses as a nature-based solution for greenhouse gas mitigation,” said study lead author Richard Unsworth, an associate professor of Biosciences at the Swansea University and the founding director of the marine conservation charity&nbsp;<a href="https://www.projectseagrass.org/">Project Seagrass</a>. “But if the ecological state of seagrasses remains compromised, then their ability to contribute to nature-based solutions for the climate emergency and biodiversity crisis remains in doubt.”



Since seagrass sensitivity to environmental stressors is acute, the risk of seagrass degradation and loss persists in many regions around the globe. Thus, fundamentally rethinking the conservation of this valuable natural resource is critical to understanding and safeguarding their part in fighting our planetary emergencies.



“Seagrasses are of fundamental importance to the planet but compared with terrestrial grasses, and even seaweeds, the body of research within seagrass is magnitudes smaller,” said Professor Unsworth. “However, there are substantial ecological, social, and regulatory barriers and bottlenecks to seagrass restoration and conservation because of the scale of the interventions required.”



“Now advances in marine robotics, molecular ecology, remote sensing, and artificial intelligence all offer new opportunities to solve conservation problems in difficult environments at unprecedented global scales. It is only by looking beyond carbon and recognizing the true value of seagrass meadows can we place it on a pathway to net zero loss and ultimately net gain,” he concluded.



The study is published in the journal <a href="http://dx.doi.org/10.1126/science.abq6923">Science</a>.



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By <a href="mailto:andrei.ionescu5891@gmail.com">Andrei Ionescu</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer&nbsp;&nbsp;

Seagrass is of "fundamental importance" to Earth's future

Scientists have long known that seagrass – the only underwater...

Hypodematium crenatum crenatum

Taxonomic tree: