Trees save lives, reduce respiratory problems

In the first broad-scale estimate of air pollution removal by trees nationwide, U.S. Forest Service scientists and collaborators calculated that trees are saving more than 850 human lives a year and preventing 670,000 incidents of acute respiratory symptoms.While trees’ pollution removal equated to an average air quality improvement of less than 1 percent, the impacts of that improvement are substantial. Researchers valued the human health effects of the reduced air pollution at nearly $7 billion every year in a study published recently in the journal Environmental Pollution.The study by Dave Nowak and Eric Greenfield of the U.S. Forest Service’s Northern Research Station and Satoshi Hirabayashi and Allison Bodine of the Davey Institute is unique in that it directly links the removal of air pollution with improved human health effects and associated health values. The scientists found that pollution removal is substantially higher in rural areas than urban areas, however the effects on human health are substantially greater in urban areas than rural areas.”With more than 80 percent of Americans living in urban area, this research underscores how truly essential urban forests are to people across the nation,” said Michael T. Rains, Director of the Forest Service’s Northern Research Station and the Forest Products Laboratory. “Information and tools developed by Forest Service research are contributing to communities valuing and managing the 138 million acres of trees and forests that grace the nation’s cities, towns and communities.”The study considered four pollutants for which the U.S. EPA has established air quality standards: nitrogen dioxide, ozone, sulfur dioxide, and particulate matter less than 2.5 microns (PM2.5) in aerodynamic diameter. Health effects related to air pollution include impacts on pulmonary, cardiac, vascular, and neurological systems. In the United States, approximately 130,000 PM2.5-related deaths and 4,700 ozone-related deaths in 2005 were attributed to air pollution.Trees’ benefits vary with tree cover across the nation. …

Read more

Fire ecology manipulation by California native cultures

Before the colonial era, 100,000s of people lived on the land now called California, and many of their cultures manipulated fire to control the availability of plants they used for food, fuel, tools, and ritual. Contemporary tribes continue to use fire to maintain desired habitat and natural resources.Frank Lake, an ecologist with the U.S. Forest Service’s Pacific Southwest Station, will lead a field trip to the Stone Lake National Wildlife Refuge during the Ecological Society of America’s 99th Annual Meeting in Sacramento, Cal., this August. Visitors will learn about plant and animal species of cultural importance to local tribes. Don Hankins, a faculty associate at California State University at Chico and a member of the Miwok people, will co-lead the trip, which will end with a visit to California State Indian Museum.Lake will also host a special session on a “sense of place,” sponsored by the Traditional Ecological Knowledge section of the Ecological Society, that will bring representatives of local tribes into the Annual Meeting to share their cultural and professional experiences working on tribal natural resources issues.”The fascinating thing about the Sacramento Valley and the Miwok lands where we are taking the field trip is that it was a fire and flood system,” said Lake. “To maintain the blue and valley oak, you need an anthropogenic fire system.”Lake, raised among the Yurok and Karuk tribes in the Klamath River area of northernmost California, began his career with an interest in fisheries, but soon realized he would need to understand fire to restore salmon. Fire exerts a powerful effect on ecosystems, including the quality and quantity of water available in watersheds, in part by reducing the density of vegetation.”Those trees that have grown up since fire suppression are like straws sucking up the groundwater,” Lake said.The convergence of the Sacramento and San Joaquin rivers was historically one of the largest salmon bearing runs on the West Coast, Lake said, and the Miwok, Patwin and Yokut tribal peoples who lived in the area saw and understood how fire was involved.California native cultures burned patches of forest in deliberate sequence to diversify the resources available within their region. The first year after a fire brought sprouts for forage and basketry. In 3 to 5 years, shrubs produced a wealth of berries. Mature trees remained for the acorn harvest, but burning also made way for the next generation of trees, to ensure a consistent future crop. …

Read more

Ants plant tomorrow’s rainforest

Tropical montane rain forests are highly threatened and their remnants are often surrounded by deforested landscapes. For the regeneration of these degraded areas, seed dispersal of forest trees plays a crucial role but is still poorly understood. Most tree species are dispersed by birds and mammals, but also by ants. A study published today in the Journal of Ecology by a team from the LOEWE Biodiversity and Climate Research Centre and the University of Halle-Wittenberg demonstrates the importance of this hitherto neglected ecosystem function for the restoration of montane rain forests. Ants promote the regeneration of these forests by dispersing seeds to safe sites for tree establishment.The Yungas, a region on the eastern slopes of the Bolivian Andes near La Paz, are marked by elongated valleys with relicts of the original mountain rain forest. Due to land-use practices like slash-and-burn agriculture and the extension of coca plantations, the forests are highly fragmented. The forest relicts are surrounded by an open, largely degraded cultural landscape. In this context, the team conducted experiments to find out to what extent ants contribute to the dispersal of a widespread, primarily bird-dispersed tree (Clusia trochiformis) and tested whether this ecosystem function may contribute to the restoration of deforested areas.The red, lipid-rich aril, a fleshy pulp surrounding the seeds of Clusia, is highly attractive to many animals. Birds are the primary dispersers. They feed on the nutritious part of the fruits, the fleshy aril, and defecate the seeds. …

Read more

Combined use of oxytocin and human chorionic gonadotropin in intractable pain patients

Two hormones credited with reducing pain and need for opioid analgesics when released naturally during pregnancy and childbirth worked similarly when administered simultaneously to patients with intractable pain, research shows.Following doses of oxytocin (OT) and human chorionic gonadotropin (HCG), 7 of 9 patients reported a 30% to 40% reduction in opioid use and baseline pain, in results reported today at the 30th Annual Meeting of the American Academy of Pain Medicine. In addition, the patients reported less intense pain flares, which are sudden exacerbations of pain that occur against a background of persistent pain, and longer periods between flares.Study author Forest Tennant, MD, said side effects were remarkably few, probably because the hormones are natural, bio-identical compounds. Dr. Tennant is an internist and addictionologist who specializes in research and treatment of intractable pain at the Veract Intractable Pain Clinics he founded in West Covina, Calif.”The benefit that these patients mostly talk about is somewhat subjective but relates to what patients routinely call a ‘feeling of well-being,’ ‘more alive,’ or [increasing] ‘will to live,” Dr. Tennant said. “They also believe the combination is one they want to continue.”Sometimes referred to as the “bonding hormone,” OT exerts powerful action in the neuroanatomy of intimacy and also acts as a neurotransmitter in the brain. HCG supports the development of the fetus during pregnancy among other roles.Both hormones surge during and after childbirth, and pregnant women have frequently exhibited reduced pain and need for opioids. Dr. Tennant has conducted previous small open-label studies that confirmed a similar effect for both hormones when administered separately in patients who suffer from intractable pain. However, no one had tested the effect of administering both hormones simultaneously until now.The study, which was cleared by the facility’s Institutional Review Board, included 9 patients with intractable pain who were being maintained on 1 or more long- and short-acting opioids. …

Read more

Large mammals were the architects in prehistoric ecosystems

Researchers from Denmark demonstrate in a study that the large grazers and browsers of the past created a mosaic of varied landscapes consisting of closed and semi-closed forests and parkland.The study is published March 3, 2014 in the Proceedings of the National Academy of Sciences.Dung beetles recount the nature of the pastThe biologists behind the new research findings synthesized decades of studies on fossil beetles, focusing on beetles associated with the dung of large animals in the past or with woodlands and trees. Their findings reveal that dung beetles were much more frequent in the previous interglacial period (from 132,000 to 110,000 years ago) compared with the early Holocene (the present interglacial period, before agriculture, from 10,000 to 5,000 years ago).”One of the surprising results is that woodland beetles were much less dominant in the previous interglacial period than in the early Holocene, which shows that temperate ecosystems consisted not just of dense forest as often assumed, but rather a mosaic of forest and parkland,” says postdoctoral fellow Chris Sandom.”Large animals in high numbers were an integral part of nature in prehistoric times. The composition of the beetles in the fossil sites tells us that the proportion and number of the wild large animals declined after the appearance of modern man. As a result of this, the countryside developed into predominantly dense forest that was first cleared when humans began to use the land for agriculture,” explains Professor Jens-Christian Svenning.Bring back the large animals to EuropeIf people want to restore self-managing varied landscapes, they can draw on the knowledge provided by the new study about the composition of natural ecosystems in the past.”An important way to create more self-managing ecosystems with a high level of biodiversity is to make room for large herbivores in the European landscape — and possibly reintroduce animals such as wild cattle, bison and even elephants. They would create and maintain a varied vegetation in temperate ecosystems, and thereby ensure the basis for a high level of biodiversity,” says senior scientist Rasmus Ejrns.The study received financial support from the 15 June Foundation and a grant from the European Research Council. To a large extent, it supports the idea that the rewilding-based approach to nature management should be incorporated to a far greater degree in nature policy in Europe -especially in the case of national parks and other large natural areas.Story Source:The above story is based on materials provided by Aarhus University. Note: Materials may be edited for content and length.

Read more

Spanish forest ecosystems: Carbon emission will be higher in second half of century

Spanish forest ecosystems will quite probably emit high quantities of carbon dioxide in the second half of the 21st century. This is the conclusion of a report that reviews the results obtained from the implementation of the forest simulation model GOTILWA+, a tool to simulate forest growth processes under several environmental conditions and to optimize Mediterranean forests management strategies in the context of climate change.The report was published on the latest issue of the ecology and environment journal Ecosistemas, edited by the Spanish Association of Terrestrial Ecology. Peer review was led by professors Santiago Sabat and Carlos Gracia, of the Department of Ecology at the University of Barcelona (UB) and the Centre for Ecological Research and Forestry Applications (CREAF), and the expert Daniel Nadal, of UB’s former Department.The study analyses data obtained from the simulation forest growth model GOTILWA+ (Growth Of Trees Is Limited by WAter), based on ecophysiological processes. The model enables to explore the effects of climate change on forestry ecosystems under changed environmental conditions and to simulate different management scenarios and compare them.Future perspectives for Spanish forestsIn climate change scenarios simulated by the model GOTILWA+ — within the Consolider-Ingenio project Montes and the research project Med-Forestream — , net primary productivity of Spanish forests (how much carbon dioxide plants take in during photosynthesis minus how much carbon dioxide they release during respiration) will decrease from the second half of this century. Consequently, woodlands that now drain carbon will become carbon producers because plant respiration (a process in which oxygen is taken in and carbon dioxide is given out) and the decomposition of death organic matter will exceed photosynthesis processes (carbon sequestration and oxygen release).GOTILWA+ also explores the responses of different forest types to water availability. Climate change involves an increase of aridity and evaporative rates. In this context, simulations show that an increase of evapotranspiration will occur in Spanish forests; it will have a negative impact on other ecosystems, for example, on rivers.The most sensitive areasThe most sensitive areas to climate change effects are Mediterranean forests of evergreen oak, Alepo pine and Scots pine, located in the south-west of the Iberian Peninsula. Forest located in the north-west will be also affected, as simulations show a severe precipitation decrease in this area. Moreover, simulations show an increase of these forests’ sensitivity to aridity. For instance, beech forests are particularly sensitive to a slight increase in average temperature as well as those forests located at low height, so altitudinal migrations will probably occur.Forest management: key to mitigate climate change impactIn the report, Gracia, Sabat and Nadal highlight that management strategies adapted to environmental changes are crucial to the conservation of Iberian forests and the resources they provide to society. …

Read more

Forest model predicts canopy competition: Airborne lasers help researchers understand tree growth

Out of an effort to account for what seemed in airborne images to be unusually large tree growth in a Hawaiian forest, scientists at Brown University and the Carnegie Institution for Science have developed a new mathematical model that predicts how trees compete for space in the canopy.What their model revealed for this particular forest of hardy native Metrosideros polymorpha trees on the windward slope of Manua Kea, is that an incumbent tree limb greening up a given square meter would still dominate its position two years later a forbidding 97.9 percent of the time. The model described online in the journal Ecology Letters could help generate similar predictions for other forests, too.Why track forest growth using remote sensing, pixel by pixel? Some ecologists could use that information to learn how much one species is displacing another over a wide area or how quickly gaps in the canopy are filled in. Others could see how well a forest is growing overall. Tracking the height of a forest’s canopy reveals how tall the trees are and therefore how much carbon they are keeping out of the atmosphere — that is, as long as scientists know how to interpret the measurements of forest growth.James Kellner, assistant professor of ecology and evolutionary biology at Brown University, the paper’s lead and corresponding author, noticed what seemed like implausibly large canopy growth in LIDAR images collected by the Carnegie Airborne Observatory over 43 hectares on the windward flank of Manua Kea. In the vast majority of pixels (each representing about a square meter) the forest growth looked normal, but in some places the height change between 2007 and 2009 seemed impossible: sometimes 10 or 15 meters.The data were correct, he soon confirmed, but the jumps in height signaled something other than vertical growth. They signaled places where one tree had managed to overtop another or where the canopy was filling in a bare spot. The forest wasn’t storing that much more carbon; taller trees were growing a few meters to the side and creating exaggerated appearances of vertical growth in the overhead images.Turning that realization into a predictive mathematical model is not a simple matter. Working with co-author Gregory P. Asner at the Carnegie Institution for Science in Stanford, Calif., Kellner created the model, which provides a probabilistic accounting of whether the height change in a pixel is likely to be the normal growth of the incumbent tree, a takeover by a neighboring tree, or another branch of the incumbent tree.Tracking treetopsThe model doesn’t just work for this forest but potentially for different kinds of forests, Kellner said, because its interpretation of the data is guided by the data itself. …

Read more

Shadowing in Sensor Images: NASA study points to ‘infrared-herring’ in apparent Amazon green-up

For the past eight years, scientists have been working to make sense of why some satellite data seemed to show the Amazon rain forest “greening-up” during the region’s dry season each year from June to October. The green-up indicated productive, thriving vegetation in spite of limited rainfall.Now, a new NASA study published today in the journal Nature shows that the appearance of canopy greening is not caused by a biophysical change in Amazon forests, but instead by a combination of shadowing within the canopy and the way that satellite sensors observe the Amazon during the dry season.Correcting for this artifact in the data, Doug Morton, of NASA’s Goddard Space Flight Center in Greenbelt, Md., and colleagues show that Amazon forests, at least on the large scale, maintain a fairly constant greenness and canopy structure throughout the dry season. The findings have implications for how scientists seek to understand seasonal and interannual changes in Amazon forests and other ecosystems.”Scientists who use satellite observations to study changes in Earth’s vegetation need to account for seasonal differences in the angles of solar illumination and satellite observation,” Morton said.Isolating the apparent green-up mechanismThe MODIS, or Moderate Resolution Imaging Spectroradiometer, sensors that fly aboard NASA’s Terra and Aqua satellites make daily observations over the huge expanse of Amazon forests. An area is likely covered in green vegetation if sensors detect a relatively small amount of red light — absorbed in abundance by plants for photosynthesis — but see a large amount of near-infrared light, which plants primarily reflect. Scientists use the ratio of red and near-infrared light as a measure of vegetation “greenness.”Numerous hypotheses have been put forward to explain why Amazon forests appear greener in MODIS data as the dry season progresses. Perhaps young leaves, known to reflect more near-infrared light, replace old leaves? Or, possibly trees add more leaves to capture sunlight in the dry season when the skies are less cloudy.Unsettled by the lack of definitive evidence explaining the magnitude of the green-up, Morton and colleagues set out to better characterize the phenomenon. They culled satellite observations from MODIS and NASA’s Ice Cloud and land Elevation Satellite (ICESat) Geosciences Laser Altimeter System (GLAS), which can provide an independent check on the seasonal differences in Amazon forest structure.The team next used a theoretical model to demonstrate how changes in forest structure or reflectance properties have distinct fingerprints in MODIS and GLAS data. Only one of the hypothesized mechanisms for the green-up, changes in sun-sensor geometry, was consistent with the satellite observations.”We think we have uncovered the mechanism for the appearance of seasonal greening of Amazon forests — shadowing within the canopy that changes the amount of near-infrared light observed by MODIS,” Morton said.Seeing the Amazon in a new lightIn June, when the sun is as low and far north as it will get, shadows are abundant. By September, around the time of the equinox, Amazon forests at the equator are illuminated from directly overhead. …

Read more

Forest harvesting intensity varies in Europe

Forests provide us with essential raw materials and the demand for these materials is increasing. To meet this increasing demand, forestry faces the challenge of how to intensify management of the existing production forests in sustainable ways.An international and multidisciplinary team of scientists led by Christian Levers from the Humboldt-Universitt in Berlin show that forest harvesting intensity is distributed unevenly across Europe and harvested timber volumes were mostly well below the increment. The spatial patterns of forest harvesting intensity were well explained by forest-resource related variables (i.e., the share of plantation species, growing stock, forest cover), site conditions (i.e., topography, accessibility), and country-specific characteristics, whereas socioeconomic variables were less important.The study provides concrete starting points for developing measures targeted at increasing regional wood supply from forests or lowering harvest pressure in regions where forests are heavily used.The research was carried out in the context of the Integrated Project “Visions of land use transitions in Europe” (VOLANTE) and supported by the European Commission and the Einstein Foundation Berlin.Story Source:The above story is based on materials provided by European Forest Institute. Note: Materials may be edited for content and length.

Read more

To calculate long-term conservation pay off, factor in people

Paying people to protect their natural environment is a popular conservation tool around the world — but figure out that return on investment, for both people and nature, is a thorny problem, especially since such efforts typically stretch on for years.”Short attention-span worlds with long attention-span problems” is how Xiaodong Chen, a former Michigan State University doctoral student now on faculty at the University of North Carolina-Chapel Hill sums it up.Chen, with his adviser Jianguo “Jack” Liu, director of the MSU Center for Systems Integration and Sustainability (CSIS) and others, have developed a new way to evaluate and model the long-term effectiveness of conservation investments. Their achievement is not only factoring in ecological gains — like, more trees growing — but also putting the actions and reactions of people into the equation.The paper, Assessing the Effectiveness of Payments for Ecosystem Services: an Agent-Based Modeling Approach, appears in this week’s online edition of Ecology and Society.The paper examines payments for ecosystem services — the practice of paying people to perform tasks or engage in practices that aid conservation. The authors examined one of China’s most sweeping — the National Forest Conservation Program, in which residents in Wolong Nature Reserve are paid to stop chopping down trees for timber and fuel wood.Chen explained they tapped into both social data and environmental information to be able to create a computer model to simulate how the policy would fare over many years in a variety of scenarios. Studies documenting results on land cover change and panda habitat dynamics were merged with studies revealing how people were likely to behave if new households were formed or incentives for conservation activities were varied.”Usually studies are developed in either the social sciences or the natural sciences, and the importance of the other perspectives are not built into scientific exploration,” Chen said. “We were able to develop this kind of simulation because of collaborative interdisciplinary research — by putting people with different backgrounds together.”He also said the model’s ability to run scenarios about how policy could work over decades is crucial because many goals of conservation, like restoring wildlife habitat, can take decades. In the meantime, the actions of individuals living in the area can change.Story Source:The above story is based on materials provided by Michigan State University. Note: Materials may be edited for content and length.

Read more

New antibiotic shows promise for treating MRSA pneumonia

Sep. 11, 2013 — A drug approved just two years ago for treating bacterial infections may hold promise for treating the potentially fatal MRSA pneumonia, according to a Henry Ford Hospital study.Researchers found that patients treated with the antibiotic ceftaroline fosamil, or CPT-F, had a lower mortality rate after 28 days than the mortality rate seen in patients treated with vancomycin, the most common drug therapy for MRSA pneumonia.In the retrospective study, 33 of 38 patients responded well to treatments of CPT-F and were discharged from the hospital after the infection cleared. Of the five patients who died, three were attributed to other serious medical conditions.The mortality rate for patients treated with vancomycin has been reported to be as high as 32 percent after 28 days. In the Henry Ford study, the mortality rate for the CPT-F treated population was 13 percent.The study is being presented Wednesday at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy meeting in Denver.”Many things fall under the umbrella of proper and appropriate MRSA pneumonia treatment, and these results present a possible benefit with the use of CPT-F,” says Samia Arshad, a Henry Ford Infectious Diseases epidemiologist and the study’s lead author. “It is critical for us to find alternative drug therapies to improve patient outcomes. Further research is needed to test the efficacy of CPT-F on a larger patient population as CPT-F offers doctors another viable option for treating patients with MRSA pneumonia.”In 2010 the U.S. Food and Drug Administration approved CPT-F, an injectable antibiotic, for treating patients with bacterial infections like community-acquired bacterial pneumonia and skin infections. Henry Ford’s study is the first to evaluate the efficacy of MRSA pneumonia patients treated with CPT-F. MRSA pneumonia is highly antibiotic resistant and most common in patients 65 years or older.Researchers evaluated 38 patients treated with CPT-F. Twenty of these patients were failing standard treatment with either vancomycin and/or cefepime, and were switched to CPT-F. …

Read more

Drug patch treatment sees new breakthrough

Sep. 6, 2013 — An assistant professor with the Virginia Tech — Wake Forest School of Biomedical Engineering has developed a flexible microneedle patch that allows drugs to be delivered directly and fully through the skin. The new patch can quicken drug delivery time while cutting waste, and can likely minimize side-effects in some cases, notable in vaccinations and cancer therapy.News of the delivery technology was published in a recent issue of the scientific journal, Advanced Materials.Leading development of the flexible patch was Lissett Bickford, now an assistant professor and researcher of biomedical engineering and the mechanical engineering, both part of the Virginia Tech College of Engineering. Work on the technology was completed while Bickford was a post-doctoral research associate at the University of North Carolina Chapel Hill.Microneedle patch technology used on the skin has existed for several years, each patch containing an array of hundreds of micron-sized needles that pierce the skin and dissolve, delivering embedded therapeutics. However, because of their rigid chemical makeup, the patches proved difficult in fully piercing into the skin, creating a waste of drug material and a slowed delivery time. Additionally, the patches also have been difficult to produce in bulk; typical fabrication procedures have required centrifugation.Bickford, with her research team, including Chapel Hill graduate student Katherine A. Moga, were able to develop a new flexible microneedle patch that forms to the skin directly — think a regular household bandage — and then fully pierces the skin and dissolves. Bickford said the softer, more malleable and water-soluble material also allows for more precise control over the shape, size, and composition of the patch, with little to no waste.The nanoparticle, micro-molding patch is based on Particle Replication In Non-wetting Templates (PRINT for short) technology, developed by University of North Carolina researcher and professor Joseph DeSimone. Unlike other methods for making these patches, the new technology allows for quicker and greater wide-scale production, reducing related costs.

Read more

400-year study finds Northeast forests resilient, changing

Sep. 5, 2013 — A joint Harvard-Smithsonian study released today in the journal PLOS ONE reveals how much — and how little — Northeastern forests have changed after centuries of intensive land use.A hike through today’s woods will reveal the same types of trees that a colonial settler would have encountered 400 years ago. But the similarities end there. Jonathan Thompson, research associate at the Smithsonian Conservation Biology Institute and lead author of the new study, explains, “If you only looked at a tree species list, you’d have the impression that Northeast forests haven’t changed. But once you start mapping the trees, and counting them up, a different picture emerges.” Thompson adds, “In some ways the forest is completely transformed.”To draw these conclusions, Thompson and his colleagues compared colonial-era tree records to modern US Forest Service data across a 9-state area stretching from Pennsylvania to Maine.Their results show stark contrasts between pre-colonial forests and today. Maples have exploded across the Northeast, their numbers increasing by more than 20 percent in most towns. Other tree types have declined sharply. Beeches, oaks, and chestnuts show the most pronounced loss — big trouble, Thompson notes, for wildlife that depend on tree nuts for winter survival.Pine numbers have shifted more than any other tree type, increasing in some places, decreasing elsewhere. Thompson pins this variability to ecology and economy: “Pine is valuable for timber, but quick to return after cutting. It has a social and environmental dynamism to it.”The nine states in the study share a similar — and notable — forest history: during the 18th and 19th centuries, more than half the forestland was cleared for agriculture and cut for timber. …

Read more

Red spruce reviving in New England, but why?

Aug. 30, 2013 — In the 1970s, red spruce was the forest equivalent of a canary in the coal mine, signaling that acid rain was damaging forests and that some species, especially red spruce, were particularly sensitive to this human induced damage. In the course of studying the lingering effects of acid rain and whether trees stored less carbon as a result of winter injury, U.S. Forest Service and University of Vermont scientists came up with a surprising result — three decades later, the canary is feeling much better.Decline in red spruce has been attributed to damage that trees sustain in winter, when foliage predisposed to injury by exposure to acid rain experiences freezing injury and dies. Paul Schaberg, a research plant physiologist with the U.S. Forest Service’s Northern Research Station in Burlington, Vt., and partners studied red spruce trees in Vermont, New Hampshire and Massachusetts. They found that the influence of a single damaging winter injury event in 2003 continued to slow tree growth in New England for 3 years, longer than had been expected, and had a significant impact on carbon storage.They also found something they did not expect.”The shocking thing is that these trees are doing remarkably well now,” said Schaberg, a co-author on the study. Researchers found that diameter growth is now the highest ever recorded for red spruce, indicating that it is now growing at levels almost two times the average for the last 100 years, a growth rate never before achieved by the trees examined. “It raises the question ‘why?'” Schaberg said.The theories that Schaberg and his colleagues are eager to test include whether the red spruce turn-around can be credited to reductions in pollution made possible by the Clean Air Act of 1990, which helped reduce sulfur and nitrogen pollution. Another possibility is that red spruce may be one of nature’s winners in the face of climate change. …

Read more

Wildfires projected to worsen with climate change

Aug. 28, 2013 — Research by environmental scientists at the Harvard School of Engineering and Applied Sciences (SEAS) brings bad news to the western United States, where firefighters are currently battling dozens of fires in at least 11 states.The Harvard team’s study suggests wildfire seasons by 2050 will be about three weeks longer, up to twice as smoky, and will burn a wider area in the western states. The findings are based on a set of internationally recognized climate scenarios, decades of historical meteorological data, and records of past fire activity.The results will be published in the October 2013 issue of Atmospheric Environment and are available in advance online.Awareness is building that gradual climate change may contribute in the coming years to increases in significant, disruptive events like severe storms and floods. Loretta J. Mickley, a senior research fellow in atmospheric chemistry at Harvard SEAS and coauthor of the new study, is thinking one step further, to secondary effects like forest fires and air quality that rely heavily on meteorological factors.”We weren’t altogether certain what we would find when we started this project,” Mickley says. “In the future atmosphere we expect warmer temperatures, which are conducive to fires, but it’s not apparent what the rainfall or relative humidity will do. Warmer air can hold more water vapor, for instance, but what does this mean for fires?””It turns out that, for the western United States, the biggest driver for fires in the future is temperature, and that result appears robust across models,” Mickley adds. “When you get a large temperature increase over time, as we are seeing, and little change in rainfall, fires will increase in size.”Reaching that conclusion with statistical confidence required months of analysis, because at the local level, wildfires are very difficult to predict.”Wildfires are triggered by one set of influences — mainly human activity and lightning — but they grow and spread according to a completely different range of influences that are heavily dependent on the weather,” says lead author Xu Yue. “Of course, when all the factors come together just right — whoosh, there’s a big fire.”By examining records of past weather conditions and wildfires, the team found that the main factors influencing the spread of fires vary from region to region. In the Rocky Mountain Forest, for example, the best predictor of wildfire area in a given year is the amount of moisture in the forest floor, which depends on the temperature, rainfall, and relative humidity that season. …

Read more

Woodland salamanders indicators of forest ecosystem recovery

Aug. 28, 2013 — Woodland salamanders are a viable indicator of forest ecosystem recovery, according to researchers from the U.S. Forest Service’s Pacific Southwest Research Station.PSW Research Wildlife Biologist Dr. Hartwell Welsh and Garth Hodgson examined two species of woodland salamanders across four stages of tree development at Mill Creek — a disturbed old-growth redwood forest in northern California. They found that the numbers and body condition of two common species of salamander tracked closely with forest stand growth, development, and structural changes. Using salamander population numbers and physiological condition on adjacent, never harvested old-growth parkland to reference advancements along this developmental pathway, they demonstrated relationships between salamander counts and body condition and aspects of forest advancement including stand age, tree size, ambient moisture, canopy closure, and litter depth.The case study established that when woodland salamanders are found in high abundance, it indicates a healthy forest, having undergone ecological advancement and ecosystem recovery.There have been concerns about using indicator species as metrics of ecosystem conditions; however, amphibians are increasingly becoming accepted as researchers verify their applicability and usefulness. The woodland salamanders evaluated in Mill Creek were deemed credible due to their conservatism, trophic role, and high site fidelity, which tie them closely to conditions of place.The findings of this case study are important because old-growth forests are quickly diminishing, but they provide crucial environmental services to society. According to the researchers, this type of forest is a unique carbon sink containing the most abundant land carbon stocks on the planet. Old-growth forests sequester carbon pollution and support the world’s most diverse ecosystems.Mill Creek is an old-growth forest located in Del Norte, Calif. in a geographically limited coastal redwood forest bioregion, which has seen extensive commercial logging for more than 100 years. …

Read more

Woodland salamanders indicators of forest ecosystem recovery

Aug. 28, 2013 — Woodland salamanders are a viable indicator of forest ecosystem recovery, according to researchers from the U.S. Forest Service’s Pacific Southwest Research Station.PSW Research Wildlife Biologist Dr. Hartwell Welsh and Garth Hodgson examined two species of woodland salamanders across four stages of tree development at Mill Creek — a disturbed old-growth redwood forest in northern California. They found that the numbers and body condition of two common species of salamander tracked closely with forest stand growth, development, and structural changes. Using salamander population numbers and physiological condition on adjacent, never harvested old-growth parkland to reference advancements along this developmental pathway, they demonstrated relationships between salamander counts and body condition and aspects of forest advancement including stand age, tree size, ambient moisture, canopy closure, and litter depth.The case study established that when woodland salamanders are found in high abundance, it indicates a healthy forest, having undergone ecological advancement and ecosystem recovery.There have been concerns about using indicator species as metrics of ecosystem conditions; however, amphibians are increasingly becoming accepted as researchers verify their applicability and usefulness. The woodland salamanders evaluated in Mill Creek were deemed credible due to their conservatism, trophic role, and high site fidelity, which tie them closely to conditions of place.The findings of this case study are important because old-growth forests are quickly diminishing, but they provide crucial environmental services to society. According to the researchers, this type of forest is a unique carbon sink containing the most abundant land carbon stocks on the planet. Old-growth forests sequester carbon pollution and support the world’s most diverse ecosystems.Mill Creek is an old-growth forest located in Del Norte, Calif. in a geographically limited coastal redwood forest bioregion, which has seen extensive commercial logging for more than 100 years. …

Read more

Oxygen-generating compound shows promise for saving tissue after severe injury

Aug. 26, 2013 — The same compound in a common household clothes detergent shows promise as a treatment to preserve muscle tissue after severe injury. Researchers at the Wake Forest Baptist Medical Center’s Institute for Regenerative Medicine hope the oxygen-generating compound could one day aid in saving and repairing limbs and tissue.The research in rats, published online ahead of print in PLOS ONE, found that injections of the compound sodium percarbonate (SPO) can produce enough oxygen to help preserve muscle tissue when blood flow is disrupted.”Some commercial detergents generate oxygen bubbles to help clean clothes or remove stains,” said Benjamin Harrison, Ph.D., co-author and associate professor of regenerative medicine at Wake Forest Baptist. “We modified the material so it can be injected into muscle and provide a boost of oxygen to slow down muscle death until surgery can restore blood flow. Potential applications include treating amputations, crush injuries from car accidents or even blast injuries suffered by those in combat zones.”SPO is a combination of sodium carbonate and hydrogen peroxide molecules. In the presence of water, it decomposes into oxygen and other salts. The current formulation used by the researchers generates oxygen for about three hours.”Normally, when blood flow to muscle tissue is reduced due to severe injury, the muscle begins to die,” said Harrison. “Providing extra oxygen to oxygen-deprived muscle following injury is currently a major medical challenge. The few treatments that are available are primarily aimed at increasing the oxygen-carrying capacity of blood and require an intact system of blood vessels to carry that fluid, which we don’t always have in damaged tissue.”When muscles don’t have enough oxygen, they lose the ability to contract and their delicate metabolic balance (homeostasis) is impaired. The current project measured the effects of injecting oxygen-starved muscles with SPO. …

Read more

Huge owls need huge trees

Aug. 15, 2013 — A study spearheaded by the Wildlife Conservation Society and the University of Minnesota has shown that the world’s largest owl — and one of the rarest — is also a key indicator of the health of some of the last great primary forests of Russia’s Far East.The study found that Blakiston’s fish owl relies on old-growth forests along streams for both breeding and to support healthy populations of their favorite prey: salmon. The large trees provide breeding cavities for the enormous bird, which has a two-meter (six-foot) wingspan. And when these dead, massive trees topple into adjacent streams, they disrupt water flow, forcing the gushing river around, over, and under these new obstacles. The result is stream channel complexity: a combination of deep, slow-moving backwaters and shallow, fast-moving channels that provide important microhabitats critical to salmon in different developmental stages.The study appears in the August issue of the journal Oryx. Authors include Jonathan Slaght of the Wildlife Conservation Society, R. J. Gutiérrez of the University of Minnesota, and Sergei Surmach of the Institute of Biology and Soils (Russian Academy of Sciences).The authors studied the foraging and nesting characteristics of Blakiston’s fish owl in Primorye, Russia, where they looked at nesting habitat over 20,213 square kilometers (7,804 square miles). They found that large old trees and riparian old-growth forest were the primary distinguishing characteristics of both nest and foraging sites.The authors say that management and conservation of old-growth forests is essential for sustaining this species because they are central to the owls’ nesting and foraging behavior. Moreover, conservation of Primorye’s forests and rivers sustains habitat for many other species: including eight salmon and trout species that spawn there; some of the 12 other owl species found in Primorye; and mammals like the endangered Amur (or Siberian) tiger, Asiatic black bear, and wild boar. …

Read more

One tree’s architecture reveals secrets of a forest

Aug. 6, 2013 — Behind the dazzling variety of shapes and forms found in trees hides a remarkably similar architecture based on fundamental, shared principles, UA ecologists have discovered.Researchers in the University of Arizona’s department of ecology and evolutionary biology have found that despite differences in appearance, trees across species share remarkably similar architecture and can tell scientists a lot about an entire forest.Just by looking at a tree’s branching pattern, it turns out, scientists can gather clues about how it functions — for example how much carbon dioxide it exchanges with the atmosphere or how much water transpires through its leaves — regardless of the tree’s shape or species.The researchers’ results, published in the August issue of the scientific journal Ecology Letters, have important implications for models used by scientists to assess how trees influence ecosystems across the globe.Studies like this enable scientists to refine models used to assess and predict functions that cannot be directly measured for an entire forest, for example how much carbon dioxide and oxygen the forest exchanges with the atmosphere and how much water the trees lose through evaporation.According to the authors, their study is the first empirical test of a theory UA ecology professor Brian Enquist helped develop in 1998. That theory holds that a tree’s branching structure — specifically, the width and length of its branches — predicts how much carbon and water a tree exchanges with the environment in relation to its overall size, independently of the species.”This theory can be used to scale the size of plants to their function, such as amount of photosynthesis, water loss and respiration, especially in light of climate change,” said Lisa Patrick Bentley, who led the research, funded by the National Science Foundation, as part of a postdoctoral fellowship in Enquist’s lab. “If you were to look at an entire forest and wanted to know how much carbon this forest puts out, our study supports the idea that you might only have to look at the properties of a few trees, representing the smallest and the largest, to figure this out.””All of the tree species we studied have very similar branching patterns regardless of their difference in appearance,” she said. “For example, even though a piñon pine tree looks very different from a maple tree, there are similar general ecological, biological and physical principles that have resulted in a similar branching architecture across those species over the course of evolution.”Bentley and her team tested this prediction in five different species of trees: maple, oak, balsa, Ponderosa pine and piñon pine. They found the theory to be correct in that it allows for predictions about a tree’s function depending on its size, and also in that the theory’s principles apply across species, despite their differences in appearance.”There is a relationship between the size and shape of branches,” Bentley said. “They grow within proportion. Take a pine tree, for example: It has the general shape of a cone, while an oak tree looks like more like an inverted cone. When you think about the many different shapes of trees, I think it’s pretty amazing that you get this correlation between such different looking trees.”For their study, the researchers harvested a total of nine specimens from forest areas set aside for research purposes. A team of undergraduate and graduate student researchers dissected the trees down to the last twig, counting the number of branches, the number of branching points, or nodes, and measuring the length and diameter of each branch.The work also confirmed an idea first proposed by Renaissance polymath Leonardo da Vinci.”If you imagine collapsing all of a tree’s outermost branches into one cylinder, that cylinder would be the size of the trunk,” Bentley said. …

Read more

Utilizzando il sito, accetti l'utilizzo dei cookie da parte nostra. maggiori informazioni

The cookie settings on this website are set to "allow cookies" to give you the best browsing experience possible. If you continue to use this website without changing your cookie settings or you click "Accept" below then you are consenting to this.

Close