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News Article | August 2, 2017
Site: www.eurekalert.org

E-cigarettes are often perceived to be less harmful than their traditional counterparts, but they could still expose the people who "vape" and those around them to harmful compounds. Researchers now report in ACS' journal Environmental Science & Technology that heavy use and secondhand emissions could lead to inhaled levels of toxins that exceed set exposure limits. But under typical use, secondhand exposure would have a lower impact on health than second- and third-hand cigarette smoke. While e-cigarettes don't produce tobacco smoke with its associated toxins, the vapors they generate contain other compounds that are potentially dangerous to human health. These include acrolein, a toxin and irritant to the eyes, skin and nasal passages; formaldehyde, which is recognized as a human carcinogen; and diacetyl, a substance that can cause respiratory problems. Hugo Destaillats and colleagues wanted to find out how much of these compounds users and others nearby might be inhaling. Vapers' intake of toxic compounds was modeled for scenarios in which different e-liquids were used with various vaporizers, battery power settings and vaping regimes. The study predicted that heavy users inhaling at a high rate of 250 puffs per day with devices at 3.8 to 4.8 volts would potentially inhale levels of acrolein (up to 10 mg per day), formaldehyde (up to 49 mg per day) and diacetyl (up to 0.5 mg per day) that exceed U.S. occupational limits of 1.3 mg per day, 0.1 mg per day and 7 micograms per day, respectively. Also, a model of indoor exposure estimated that in bars where vaping is permitted, formaldehyde and acrolein levels would often exceed California reference exposure limits. In comparison to secondhand and thirdhand tobacco smoke, the researchers computed that "disability-adjusted life years" lost due to exposure to secondhand vapor would be one to two orders of magnitude lower under typical vaping use. The authors acknowledge major funding from the University of California Tobacco-Related Disease Research Program (TRDRP). Additional funding came from Argentina's National Scientific and Technical Research Council (CONICET), the Agencia Nacional de Promoción Científica y Tecnológica (Argentina) and the U.S. National institute on Drug Abuse. The paper's abstract will be available on Aug. 2 here: http://pubs. The American Chemical Society is a not-for-profit organization chartered by the U.S. Congress. ACS is the world's largest scientific society and a global leader in providing access to chemistry-related research through its multiple databases, peer-reviewed journals and scientific conferences. ACS does not conduct research, but publishes and publicizes peer-reviewed scientific studies. Its main offices are in Washington, D.C., and Columbus, Ohio. To automatically receive news releases from the American Chemical Society, contact newsroom@acs.org.


News Article | July 17, 2017
Site: www.eurekalert.org

UPTON, NY--Scientists at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory had just finished an experiment with a two-dimensional (2D) structure they synthesized for catalysis research when, to their surprise, they discovered that atoms of argon gas had gotten trapped inside the structure's nanosized pores. Argon and other noble gases have previously been trapped in three-dimensional (3D) porous materials, but immobilizing them on surfaces had only been achieved by either cooling the gases to very low temperatures to condense them, or by accelerating gas ions to implant them directly into materials. "We are the first team to trap a noble gas in a 2D porous structure at room temperature," said Anibal Boscoboinik, a materials scientist at Brookhaven Lab's Center for Functional Nanomaterials (CFN), a DOE Office of Science User Facility where part of the research was conducted. This achievement, reported in a paper published today in Nature Communications, will enable scientists to use traditional surface-science tools--such as x-ray photoelectron and infrared reflection absorption spectroscopy--to perform detailed studies of single gas atoms in confinement. The knowledge gained from such research could inform the design, selection, and improvement of adsorbent materials and membranes for capturing gases such as radioactive krypton and xenon generated by nuclear power plants. The team of scientists from Brookhaven Lab, Stony Brook University, and the National University of San Luis in Argentina synthesized 2D aluminosilicate (composed of aluminum, silicon, and oxygen) films on top of a ruthenium metal surface. The scientists created this 2D model catalyst material to study the chemical processes happening in the industrially used 3D catalyst (called a zeolite), which has a cage-like structure with open pores and channels the size of small molecules. Because the catalytically active surface is enclosed within these cavities, it is difficult to probe with traditional surface-science tools. The 2D analogue material has the same chemical composition and active site as the 3D porous zeolite but its active site is exposed on a flat surface, which is easier to access with such tools. To confirm that the argon atoms were trapped in these "nanocages," the scientists exposed the 2D material to argon gas and measured the kinetic energy and number of electrons ejected from the surface after striking it with an x-ray beam. They performed these studies at the former National Synchrotron Light Source I (NSLS-I) and its successor facility, NSLS-II (both DOE Office of Science User Facilities at Brookhaven), with an instrument developed and operated by the CFN. Because the binding energies of core electrons are unique to each chemical element, the resulting spectra reveal the presence and concentration of elements on the surface. In a separate experiment conducted at the CFN, they grazed a beam of infrared light over the surface while introducing argon gas. When atoms absorb light of a specific wavelength, they undergo changes in their vibrational motions that are specific to that element's molecular structure and chemical bonds. To get a better understanding of how the framework itself contributes to caging, the scientists investigated the trapping mechanism with silicate films, which are similar in structure to the aluminosilicates but contain no aluminum. In this case, they discovered that not all of the argon gets trapped in the cages--a small amount goes to the interface between the framework and ruthenium surface. This interface is too compressed in the aluminosilicate films for argon to squeeze in. After studying adsorption, the scientists examined the reverse process of desorption by incrementally increasing the temperature until the argon atoms completely released from the surface at 350 degrees Fahrenheit. They corroborated their experimental spectra with theoretical calculations of the amount of energy associated with argon entering and leaving the cages. In another infrared spectroscopy experiment conducted in Brookhaven's Chemistry Division, they explored how the presence of argon in the cages affects the passage of carbon monoxide molecules through the framework. They found that argon restricts the number of molecules that adsorb onto the ruthenium surface. "In addition to trapping small atoms, the cages could be used as molecular sieves for filtering carbon monoxide and other small molecules, such as hydrogen and oxygen," said first author Jian-Qiang Zhong, a CFN research associate. While their main goal going forward will be to continue investigating zeolite catalytic processes on the 2D material, the scientists are interested in learning the impact of different pore sizes on the materials' ability to trap and filter gas molecules. "As we seek to better understand the material, interesting and unexpected findings keep coming up," said Boscoboinik. "The ability to use surface-science methods to understand how a single atom of gas behaves when it is confined in a very small space opens up lots of interesting questions for researchers to answer." This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility at Lawrence Berkeley National Laboratory, and was supported by Brookhaven's Laboratory Directed Research and Development program and the National Scientific and Technical Research Council (CONICET) of Argentina. Brookhaven National Laboratory is supported by the Office of Science of the U.S. Department of Energy. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.


Home > Press > Studying Argon Gas Trapped in Two-Dimensional Array of Tiny "Cages": Understanding how individual atoms enter and exit the nanoporous frameworks could help scientists design new materials for gas separation and nuclear waste remediation Abstract: Scientists at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory had just finished an experiment with a two-dimensional (2D) structure they synthesized for catalysis research when, to their surprise, they discovered that atoms of argon gas had gotten trapped inside the structure's nanosized pores. Argon and other noble gases have previously been trapped in three-dimensional (3D) porous materials, but immobilizing them on surfaces had only been achieved by either cooling the gases to very low temperatures to condense them, or by accelerating gas ions to implant them directly into materials. "We are the first team to trap a noble gas in a 2D porous structure at room temperature," said Anibal Boscoboinik, a materials scientist at Brookhaven Lab's Center for Functional Nanomaterials [https://www.bnl.gov/cfn/] (CFN), a DOE Office of Science User Facility where part of the research was conducted. This achievement, reported in a paper published today in Nature Communications [ https://www.nature.com/articles/ncomms16118 ], will enable scientists to use traditional surface-science tools-such as x-ray photoelectron and infrared reflection absorption spectroscopy-to perform detailed studies of single gas atoms in confinement. The knowledge gained from such research could inform the design, selection, and improvement of adsorbent materials and membranes for capturing gases such as radioactive krypton and xenon generated by nuclear power plants. The team of scientists from Brookhaven Lab, Stony Brook University, and the National University of San Luis in Argentina synthesized 2D aluminosilicate (composed of aluminum, silicon, and oxygen) films on top of a ruthenium metal surface. The scientists created this 2D model catalyst material to study the chemical processes happening in the industrially used 3D catalyst (called a zeolite), which has a cage-like structure with open pores and channels the size of small molecules. Because the catalytically active surface is enclosed within these cavities, it is difficult to probe with traditional surface-science tools. The 2D analogue material has the same chemical composition and active site as the 3D porous zeolite but its active site is exposed on a flat surface, which is easier to access with such tools. To confirm that the argon atoms were trapped in these "nanocages," the scientists exposed the 2D material to argon gas and measured the kinetic energy and number of electrons ejected from the surface after striking it with an x-ray beam. They performed these studies at the former National Synchrotron Light Source I (NSLS-I) and its successor facility, NSLS-II [ https://www.bnl.gov/ps/ ] (both DOE Office of Science User Facilities at Brookhaven), with an instrument developed and operated by the CFN. Because the binding energies of core electrons are unique to each chemical element, the resulting spectra reveal the presence and concentration of elements on the surface. In a separate experiment conducted at the CFN, they grazed a beam of infrared light over the surface while introducing argon gas. When atoms absorb light of a specific wavelength, they undergo changes in their vibrational motions that are specific to that element's molecular structure and chemical bonds. To get a better understanding of how the framework itself contributes to caging, the scientists investigated the trapping mechanism with silicate films, which are similar in structure to the aluminosilicates but contain no aluminum. In this case, they discovered that not all of the argon gets trapped in the cages-a small amount goes to the interface between the framework and ruthenium surface. This interface is too compressed in the aluminosilicate films for argon to squeeze in. After studying adsorption, the scientists examined the reverse process of desorption by incrementally increasing the temperature until the argon atoms completely released from the surface at 350 degrees Fahrenheit. They corroborated their experimental spectra with theoretical calculations of the amount of energy associated with argon entering and leaving the cages. In another infrared spectroscopy experiment conducted in Brookhaven's Chemistry Division [ https://www.bnl.gov/chemistry/ ], they explored how the presence of argon in the cages affects the passage of carbon monoxide molecules through the framework. They found that argon restricts the number of molecules that adsorb onto the ruthenium surface. "In addition to trapping small atoms, the cages could be used as molecular sieves for filtering carbon monoxide and other small molecules, such as hydrogen and oxygen," said first author Jian-Qiang Zhong, a CFN research associate. While their main goal going forward will be to continue investigating zeolite catalytic processes on the 2D material, the scientists are interested in learning the impact of different pore sizes on the materials' ability to trap and filter gas molecules. "As we seek to better understand the material, interesting and unexpected findings keep coming up," said Boscoboinik. "The ability to use surface-science methods to understand how a single atom of gas behaves when it is confined in a very small space opens up lots of interesting questions for researchers to answer." This research used resources of the National Energy Research Scientific Computing Center [ http://www.nersc.gov ], a DOE Office of Science User Facility at Lawrence Berkeley National Laboratory, and was supported by Brookhaven's Laboratory Directed Research and Development [https://science.energy.gov/lp/laboratory-directed-research-and-development/ ] program and the National Scientific and Technical Research Council (CONICET) of Argentina. About Brookhaven National Laboratory Brookhaven National Laboratory is supported by the Office of Science of the U.S. Department of Energy. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov [ http://science.energy.gov/ ]. For more information, please click If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.


News Article | July 12, 2017
Site: www.eurekalert.org

Nesting in cavities provides birds with some protection from predators -- but it isn't foolproof. A new study from The Auk: Ornithological Advances explores how Poland's cavity-nesting Marsh Tits deal with predator attacks and finds that while tactics such as small entrances and solid walls do help, adaptations like this can only take the birds so far. Wroc?aw University's Tomasz Weso?owski has spent nearly thirty years monitoring Marsh Tit nest cavities in Poland's Bia?owie?a Forest, comparing nests that are destroyed with nests that are attacked but survive. He has found that a nest's chance of survival depends on the predator's technique--broods are least likely to survive (10%) when the predator manages to get into the cavity through the existing entrance, more likely (29%) when the predator uses its paws or beak to pluck out the nest contents, and most likely to survive (39%) when the predator tries to enlarge the opening or make a new one. Tits' antipredator tactics vary in their effectiveness depending on the predator; attacks by Great Spotted Woodpeckers were successful only 60% of the time, while forest dormice were 100% successful. The results show that despite the constant pressure of natural selection, Marsh Tits can only improve their antipredator tactics so much--there are limits to adaptation. Small, narrow entrances don't work against small predators and are only effective when combined with cavity walls made of solid (not decomposing) wood; nests that were deep in a cavity, out of reach of the entrance, are safest, but birds seldom place their nests that way, suggesting that cavities that are too deep may cause other problems for Marsh Tit parents. The Bia?owie?a Forest, one of the last remaining tracts of old-growth forest in Europe, is an ideal place to study cavity-nesting birds, full of cavities of every size and shape for Marsh Tits to choose from. However, the fieldwork was not without its difficulties. "The Bia?owie?a Forest still contains fragments of primeval origin," says Weso?owski. "The work is challenging, as the old-growth stands are very tall. Marsh Tits breed at very low densities, and on average one has to search five to seven hectares of this forest to find a single breeding cavity. It requires much patience and determination." "To understand the evolution of nesting behaviors, many ornithologists attempt to quantify the trade-offs that birds face in warding off nest predators. Usually we do this by comparing nests that fail versus nests that succeed, but that approach is limited because we can't tease apart the multiple factors, including chance, that contributed to making a nest successful," according to Kristina Cockle of the National Scientific and Technical Research Council of Argentina (CONICET), an ornithologist not involved with the study who has worked extensively on nest cavities. "The new study by Weso?owski compares, instead, nests that were depredated to nests that were attacked but survived. With this approach, the author was able to identify the physical attributes of tree cavities that foiled a suite of nest attackers from woodpeckers to dormice." "Failed predator attacks: A study of tree cavities used by nesting Marsh Tits (Poecile palustris) for security" will be available July 12, 2017, at http://www. (issue URL http://www. ).


News Article | July 12, 2017
Site: phys.org

A marsh tit brings nest material to a cavity, which will help protect its young from predators. Credit: M. Arndt Nesting in cavities provides birds with some protection from predators—but it isn't foolproof. A new study from The Auk: Ornithological Advances explores how Poland's cavity-nesting Marsh Tits deal with predator attacks and finds that while tactics such as small entrances and solid walls do help, adaptations like this can only take the birds so far. Wroc?aw University's Tomasz Weso?owski has spent nearly thirty years monitoring Marsh Tit nest cavities in Poland's Bia?owie?a Forest, comparing nests that are destroyed with nests that are attacked but survive. He has found that a nest's chance of survival depends on the predator's technique—broods are least likely to survive (10%) when the predator manages to get into the cavity through the existing entrance, more likely (29%) when the predator uses its paws or beak to pluck out the nest contents, and most likely to survive (39%) when the predator tries to enlarge the opening or make a new one. Tits' antipredator tactics vary in their effectiveness depending on the predator; attacks by Great Spotted Woodpeckers were successful only 60% of the time, while forest dormice were 100% successful. The results show that despite the constant pressure of natural selection, Marsh Tits can only improve their antipredator tactics so much—there are limits to adaptation. Small, narrow entrances don't work against small predators and are only effective when combined with cavity walls made of solid (not decomposing) wood; nests that were deep in a cavity, out of reach of the entrance, are safest, but birds seldom place their nests that way, suggesting that cavities that are too deep may cause other problems for Marsh Tit parents. The Bia?owie?a Forest, one of the last remaining tracts of old-growth forest in Europe, is an ideal place to study cavity-nesting birds, full of cavities of every size and shape for Marsh Tits to choose from. However, the fieldwork was not without its difficulties. "The Bia?owie?a Forest still contains fragments of primeval origin," says Weso?owski. "The work is challenging, as the old-growth stands are very tall. Marsh Tits breed at very low densities, and on average one has to search five to seven hectares of this forest to find a single breeding cavity. It requires much patience and determination." "To understand the evolution of nesting behaviors, many ornithologists attempt to quantify the trade-offs that birds face in warding off nest predators. Usually we do this by comparing nests that fail versus nests that succeed, but that approach is limited because we can't tease apart the multiple factors, including chance, that contributed to making a nest successful," according to Kristina Cockle of the National Scientific and Technical Research Council of Argentina (CONICET), an ornithologist not involved with the study who has worked extensively on nest cavities. "The new study by Weso?owski compares, instead, nests that were depredated to nests that were attacked but survived. With this approach, the author was able to identify the physical attributes of tree cavities that foiled a suite of nest attackers from woodpeckers to dormice." Explore further: Nest size variation not related to breeding success More information: "Failed predator attacks: A study of tree cavities used by nesting Marsh Tits (Poecile palustris) for security" The Auk: Ornithological Advances, www.bioone.org/doi/full/10.1642/AUK-17-51.1


News Article | May 31, 2017
Site: www.nature.com

Emmett Duffy was about 5 metres under water off the coast of Panama, when a giant, tan-and-white porcupinefish caught his eye. The slow-moving creature would have been a prime target for predators if not for the large, treelike branches of elkhorn coral (Acropora palmata) it was sheltering under. The sighting was a light-bulb moment for Duffy, a marine biologist. He'd been to places in the Caribbean where corals were more abundant and more diverse, but smaller; the fish there were always small, too. Here, in the Bocas Del Toro archipelago, he was seeing a variety of big fish among the elkhorns. “The reason these large fish were able to thrive,” he says, “was that there were places for them to hide and places for them to live.” For Duffy, that encounter with the porcupinefish (Diodon hystrix) brought to life a concept that had long been simmering in the back of his head: that the health of an ecosystem may depend not only on the number of species present, but also on the diversity of their traits. This idea, which goes by the name of functional-trait ecology, had been part of his lab work for years but had always felt academic and abstract, says Duffy, now director of the Smithsonian Institution's Tennenbaum Marine Observatories Network in Washington DC. It's an idea that's increasingly in vogue for ecologists. Biodiversity, it states, doesn't have to be just about the number of a species in an ecosystem. Equally important to keeping an ecosystem healthy and resilient are the species' different characteristics and the things they can do — measured in terms of specific traits such as body size or branch length. That shift in thinking could have big implications for ecology. It may be necessary for understanding and forecasting how plants and animals cope with a changing climate. And functional diversity has started to influence how ecologists think about conservation; some governments have even started to incorporate traits into their management policies. Belize, for example, moved several years ago to protect parrotfish species from overfishing — not necessarily because their numbers are dwindling, but because the fish clean algae from coral and are crucial to reef survival. “Just going for species numbers basically doesn't allow us to harness all this incredibly rich information we have of how the real world operates,” says Sandra Díaz, an ecologist with Argentina's National Scientific and Technical Research Council (CONICET) and the University of Córdoba. Still, some experts are concerned. How traits are defined remains a source of debate, and without robust data on trait and species diversity in settings around the world, any choices directed by the approach could turn out to be short-sighted. “I'm really excited, but I worry,” says Walter Jetz, an ecologist and evolutionary biologist at Yale University in New Haven, Connecticut. “We as a community need to be really careful in appreciating the data limitations that exist.” For decades, the study of biodiversity was essentially a numbers game: the more species an ecosystem had, the more stable and resilient to change it was thought to be. That mindset made sense because there was so little information available about the structures of an ecosystem and the functions of species within it. The technology didn't exist to measure many traits or to process the large amount of data that would have resulted if they could have been measured. Various developments have changed that. Advances in molecular biology have enabled the study of microbes en masse. Satellites can assess traits such as tree-canopy height and marine plankton productivity. And leaps in statistical tools and computing power have helped to make use of all the data that are now being generated. Some trace the new way of thinking about ecosystems — at least in formal research — to ecologist David Tilman at the University of Minnesota in St Paul. In 1994, he published a landmark paper1 that tracked species diversity in Minnesota grasslands through a major drought in the 1980s. Species-rich areas tended to weather the drought much better than those with few species, supporting the link between diversity and stability. But the relationship wasn't linear. Only a few drought-resistant grasses were needed to greatly enhance a plot's ability to rebound. Three years later, Tilman and his collaborators published findings2 from 289 grassland plots they had planted with varying numbers of species and levels of functional diversity. Here, the presence of certain traits, such as the C photosynthesis pathway or nitrogen fixation, made a bigger difference to the plots' overall health than the number of species. Around the same time, Shahid Naeem, director of Columbia University's Earth Institute Center for Environmental Sustainability in New York City, was also looking beyond species numbers to study ecosystem function, zeroing in on the diversity of species at different levels of the food web. Looking at species number alone, he says, is like listing the parts of a car without saying what they do. That provides no guidance for when things start to break down, he says. “We just sort of stand there scratching our heads like primitive people who've never seen a car before, saying, 'The car's not working now, I wonder what's wrong with it'.” From the mid-1990s, studies of functional diversity started to take root. Work on plants and forests led the charge because it is relatively easy to manipulate such systems. But the approach gradually expanded to include birds, sea life and soils. Diana Wall, a soil ecologist at Colorado State University in Fort Collins, says that she and her colleagues have focused on functional traits and diversity for years, in part because the activities of soil microorganisms are often easier to identify than the species themselves. She is excited that researchers are developing a firmer grasp of traits and species above and below ground. “New knowledge on both fronts brings us understanding of the dependence on species and functions,” she says. Conservation biologists are excited about functional traits because they could influence decisions about what to protect. Researchers and environmentalists have typically focused on regions brimming with species, such as the Amazon rainforest and Australia's Great Barrier Reef. But Rick Stuart-Smith, an ecologist at the University of Tasmania in Taroona, Australia, has suggested reframing the definition of a biodiversity hotspot. Integrating functional traits could point to the importance of previously understudied areas. For Stuart-Smith, it's too early to identify specific places that would qualify — more in-depth research is needed. But, he says, functional-trait ecology should ultimately extend to conservation strategies and how governments choose which areas to protect. And the new way of thinking about diversity could reveal vulnerabilities that weren't recognized before. Species-rich areas may seem to have a sort of insurance against loss of traits because the functions the traits provide are assumed to be found in many species, says David Mouillot, a marine ecologist at the University of Montpellier in France. But some functions are provided by only one species, or a few. He and his colleagues are racing to locate these rare functions. The lens of functional diversity helps to create a more nuanced picture of ecosystems. Greg Asner, an ecologist with the Carnegie Institution for Science's Department of Global Ecology at Stanford University in California, has used a unique spectral imager to map 15 traits for forests across Peru. Conventional studies recognized three types of forest in the country using the species-richness concept, says Asner — dryland, floodplain and swamp forest. But Asner and his team looked at which traits could help to distinguish new functional groups, and found that seven were key. They then classified the forests based on those traits, and came up with 36 classes representing different combinations of the seven traits3. The researchers used their findings to help Peru rebalance its conservation portfolio. Asner says he's also been asked to identify a 400,000-hectare area in northern Borneo to set aside for protection on the basis of traits. “They want to know, where is the million acres where you can get the most variation in traits?” he says. “Where can you put a fence around the most functional variation?” That level of interest is encouraging to him and other researchers because ecosystems are so complex that once certain species, functions or ecosystem processes are lost, there's no getting them back — at least not using current techniques or knowledge. “We don't have the science or technology on Earth to engineer a forest from scratch the way that nature and evolution have,” says Asner. Some experts, however, advise against making decisions based on functional traits until more complete data are available. “As soon as you're missing a single species in your data matrix, you may be missing a key function that is only represented by that species,” says Jetz, who has studied functional traits in plants and vertebrate animals, particularly birds. He warns not only about gaps in data, but also about biases — such as where researchers choose to sample, which can skew a data set towards or away from certain regions or types of environment. Naeem, too, would like to see a concerted global effort to create a more complete and comprehensive database of traits for the natural world. “When we get really excited about a field, one of the big, major investments and efforts that everybody has to get behind is getting the data that we need,” he says. Some work is afoot to build such databases for both terrestrial and aquatic environments. TRY, hosted at the Max Planck Institute for Biogeochemistry in Jena, Germany, is an international network of plant scientists who have been building a publicly accessible database of traits and functions since 2007. It now contains records for 100,000 plant species. There's also the ReeFish database, now led by Mouillot, which aims to provide trait and geographic information for all tropical reef fish. And the Reef Life Survey, begun in Tasmania by Stuart-Smith and marine ecologist Graham Edgar in 2007, has trait records for more than 5,000 species from all ocean basins. Duffy, meanwhile, is spearheading the Smithsonian's Marine Global Earth Observatory programme, which he says is a “major opportunity to map out the links between diversity and functioning of marine ecosystems on a global scale”. There are currently ten sites in the network, which aims to establish a global, pole-to-pole presence. These are all works in progress, and despite wide agreement on the importance of focusing on functional traits across ecosystems, there doesn't yet seem to be a clear definition of what a trait is. Agreeing on one that spans the plant and animal kingdoms will be difficult. How detailed should one get? Is it appropriate to stop at observable traits, such as leaf size, or to dig into individual gene sequences? Diet seems to be a grey area. Some researchers include dietary patterns when they evaluate an organism's functional traits, for example, by looking at whether it can eat a variety of organisms or is specialized to feed on a single flower species. Others scoff at including diet. “If it's not on a genome, it's not a trait,” says Naeem, who points out that foxes may have certain dietary preferences, but will still eat packaged dog food, given the chance. He says that traits linked to genes — tooth size in a predator, for example — will influence diet and can be used to infer feeding patterns. Interactions between species open up another area of debate. Some might interpret a porcupinefish taking shelter among corals, as Duffy observed in Panama, as an interaction between species — and not count it as a trait. For Duffy, however, traits can influence, and be a reflection of, how species interact with each other. The traits of the coral — its branch structure and size — are what enabled the fish to thrive. Whether or not to rank the importance of traits to an ecosystem is another area of contention. Some researchers are working to identify the most valuable traits, whereas others, such as Mouillot, take a more agnostic approach. “We do not rank them. We do not say two or three traits are the most important and the other ones are marginal,” he says. And for all the focus on functional diversity, it is probably just one step towards finding a truly comprehensive view of biodiversity — the ultimate goal for ecologists and conservationists. Simultaneous work is being done on the evolutionary histories of species in an ecosystem in an attempt to understand and mitigate the effects of biodiversity loss. Some view this 'phylogenetic diversity' as the third leg of the stool with functional and species diversity. And researchers around the world are working to fill in other gaps, too. A large German consortium has been studying how land-use intensification affects functional diversity, and more work needs to be done on the role of spatial data and interactions at the landscape level, rather than in microcosms or individual study sites. For now, however, researchers are embracing functional traits for the sophistication they have already added to understanding of ecosystems. That includes Jetz — despite his warnings against making decisions based on functional diversity too soon. The data may be incomplete, but functional traits could potentially convey the importance of ecosystems to people outside the scientific community, including policymakers and economists, in a more tangible way than species richness ever has. “If you lose a species or two, it's hard to interpret what that means,” Jetz says. But being able to show explicitly how the loss of a function could decimate an ecosystem might have a bigger impact. “It's something that more people are able to relate to.”


Halis Y.,Scientific and Technical Research | Benhaddya M.L.,Scientific and Technical Research | Bachi O.E.,Scientific and Technical Research | Lahcini A.,Scientific and Technical Research | And 2 more authors.
Trees - Structure and Function | Year: 2014

Key message By using a simple and rapid technique, the degree of vessel deviations in the stem xylem could be evaluated and compared between different plant species. The degree of vessel deviations was suggested to be one of the main factors determining the hydraulic integration in woody stems. Abstract The main objective of this study was to investigate the role of vessel tangential deviations in determining both intervessel connectivity and patterns of hydraulic integration in woody stems of six Fabaceae trees. It was hypothesized that increasing the degree of vessel deviations would increase lateral contacts between vessels thereby increasing hydraulic integration within stems. Species-specific differences in vessel deviations and intervessel connectivity were quantified by following the movement of an apoplastic dye that was injected to a limited number of vessels. Intervessel connectivity was measured as the number of laterally connected vessels, whereas the degree of vessel deviations was measured as the magnitude of divergence of a group of neighboring vessels. Hydraulic integration index was determined as the ratio of tangential to axial conductance. Results showed that the degree of vessel deviations differed significantly between species. Acacia cyanophylla showed the lowest degree of vessel deviations (1.75 ± 0.33), while the highest degree was observed in Acacia etbaica (2.48 ± 0.26). Hydraulic integration was positively correlated more with vessel deviations than with intervessel connectivity. Only a very weak positive correlation was observed between vessel deviations and intervessel connectivity. Tangential deviations in the course of vessels might be one of the main factors determining the patterns of integrated-sectored transport in woody stems and, consequently, might have ecological implications in terms of plant adaptation to various ecological conditions. This study confirmed the complexity of interactions in the xylem hydraulic system. © Springer-Verlag Berlin Heidelberg 2014.

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