Posts tagged diversity
CU scientists seek solution to the mystery of ever-increasing frog deformities
0February 14, 2013
CU-Boulder amphibian study shows how
biodiversity can protect against disease
The richer the assortment of amphibian species living in a pond, the more protection that community of frogs, toads and salamanders has against a parasitic infection that can cause severe deformities, including the growth of extra legs, according to a new study by the University of Colorado Boulder.
The findings, published Feb. 14 in the journal Nature, support the idea that greater biodiversity in larger-scale ecosystems, such as forests or grasslands, may also provide greater protection against diseases, including those that attack humans. For example, a larger number of mammal species in an area may curb cases of Lyme disease, while a larger number of bird species may slow the spread of West Nile virus.
“How biodiversity affects the risk of infectious diseases, including those of humans and wildlife, has become an increasingly important question,” said Pieter Johnson, an assistant professor in the Department of Ecology and Evolutionary Biology and lead author of the study. “But as it turns out, solidly testing these linkages with realistic experiments has proven very challenging in most systems.”
Researchers have struggled to design comprehensive studies that could illuminate the possible connection between disease transmission and the number of species living in complex ecosystems. Part of the problem is simply the enormous number of organisms that may need to be sampled and the vast areas over which those organisms may roam.
The new CU-Boulder study overcomes that problem by studying smaller, easier-to-sample ecosystems. Johnson and his team visited hundreds of ponds in California, recording the types of amphibians living there as well as the number of snails infected by the pathogen Ribeiroia ondatrae. Snails are an intermediate host used by the parasite during part of its life cycle.
“One of the great challenges in studying the diversity-disease link has been collecting data from enough replicate systems to differentiate the influence of diversity from background ‘noise,’ ” Johnson said. “By collecting data from hundreds of ponds and thousands of amphibian hosts, our group was able to provide a rigorous test of this hypothesis, which has relevance to a wide range of disease systems.”
Johnson’s team buttressed its field observations both with laboratory tests designed to measure how prone to infection each amphibian species is and by creating pond replicas outside using large plastic tubs stocked with tadpoles that were exposed to a known number of parasites. All of the experiments told the same story, Johnson said. Greater biodiversity reduced the number of successful amphibian infections and the number of deformed frogs.
A normal and a deformed bullfrog
In all, the CU-Boulder researchers spent three years sampling 345 wetlands and recording malformations — which include missing, misshapen or extra sets of hind legs — caused by parasitic infections in 24,215 amphibians. They also cataloged 17,516 snails. The results showed that ponds with half a dozen amphibian species had a 78 percent reduction in parasite transmission compared to ponds with just one amphibian species. The research team also set up experiments in the lab and outdoors using 40 artificial ponds, each stocked with 60 amphibians and 5,000 parasites.
The reason for the decline in parasitic infections as biodiversity increases is likely related to the fact that ponds add amphibian species in a predictable pattern, with the first species to appear being the most prone to infection and the later species to appear being the least prone. For example, the research team found that in a pond with just one type of amphibian, that amphibian was almost always the Pacific chorus frog, a creature that is able to rapidly reproduce and quickly colonize wetland habitats, but which is also especially vulnerable to infection and parasite-induced deformities.
On the other hand, the California tiger salamander was typically one of the last species to be added to a pond community and also one of the most resistant to parasitic infection. Therefore, in a pond with greater biodiversity, parasites have a higher chance of encountering an amphibian that is resistant to infection, lowering the overall success rate of transmission between infected snails and amphibians.
This same pattern — of less diverse communities being made up of species that are more susceptible to disease infection — may well play out in more complex ecosystems as well, Johnson said. That’s because species that disperse quickly across ecosystems appear to trade off the ability to quickly reproduce with the ability to develop disease resistance.
“This research reaches the surprising conclusion that the entire set of species in a community affects the susceptibility to disease,” said Doug Levey, program director in the National Science Foundation’s Division of Environmental Biology, which helped fund the research. “Biodiversity matters.”
The sheer magnitude of the recent study also reinforces the connection between deformed frogs and parasitic infection, Johnson said. Beginning in the mid-1990s reports of frogs with extra, missing or misshapen legs skyrocketed, attracting widespread attention in the media and motivating scientists to try to figure out the cause. Johnson was among the researchers who found evidence of a link between infection with Ribeiroia and frog deformities, though the apparent rise in reports of deformations, and its underlying cause, remains controversial.
While the new study has implications beyond parasitic infections in amphibians, it does not mean that an increase in biodiversity always results in a decrease in disease, Johnson cautioned. Other factors also affect rates of disease transmission. For example, a large number of mosquitoes hatching in a particular year will increase the risk of contracting West Nile virus, even if there has been an increase in the biodiversity of the bird population. Birds act as “reservoir hosts” for West Nile virus, harboring the pathogen indefinitely with no ill effects and passing the pathogen onto mosquitoes.
“Our results indicate that higher diversity reduces the success of pathogens in moving between hosts,” Johnson said. “Nonetheless, if infection pressure is high, for instance in a year with high abundance of vectors, there will still be a significant risk of disease; biodiversity will simply function to dampen transmission success.”
CU-Boulder graduate students Dan Preston and Katie Richgels co-authored the study along with Jason Hoverman, a former postdoctoral researcher in Johnson’s lab who is now an assistant professor at Purdue. The research was funded by NSF, the National Geographic Society and the David and Lucile Packard Foundation.
To view photos and a video about the research, visit http://freshwatersillustrated.org/link/AmphibianDeformities.
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2012 CU Diversity and Inclusion Summit invites participants to ‘Amp it up’
0November 5, 2012
The University of Colorado Boulder’s annual Diversity and Inclusion Summit will feature a variety of sessions for students, faculty, staff and community members from Nov. 13-15. All events are free, open to the public and on the Boulder campus.
The organizing theme for this year’s summit is “AMP it up! Awareness, Movement and Practice.” Along with sessions on awareness, inclusiveness and classroom and campus diversity practice, a selection of events will focus on the physical embodiment of diversity. These sessions will include dance, martial arts, yoga and theater as physical opportunities to discuss and engage with diversity. Sessions with a focus on pedagogical best practices for inclusive classrooms are another highlight of this year’s summit.
“The planning committee has been a model of the kind of cooperation that Chancellor DiStefano recently called for in his State of the Campus address,” said Alphonse Keasley, CU-Boulder’s assistant vice chancellor for campus climate and community engagement. “The members have worked tirelessly to organize a summit that speaks to this year’s theme, ‘AMP it up! Awareness, Movement and Practice.’ We sincerely hope and expect that participants will gain much from the sessions for truly amping it up for diversity, inclusion and social justice.”
Peggy McIntosh, associate director of the Wellesley College Center for Research on Women, returns to the summit and will share her new research in the keynote address “Using Privilege as a Catalyst for Change” on Tuesday, Nov. 13, at 9:15 a.m. in the University Memorial Center’s Glenn Miller Ballroom. McIntosh is best known for her essay “White Privilege: Unpacking the Invisible Knapsack,” and last spoke in association with the summit in 2009, and on the Boulder campus in 2001.
Highlighted sessions during this year’s summit include:
– Tuesday, Nov. 13, 12:30 p.m., UMC Glenn Miller Ballroom.
“When Green Means Money: Economic Diversity in Boulder,” presented by Boulder City Manager Jane Brautigam.
– Tuesday, Nov. 13, 2 p.m., UMC Glenn Miller Ballroom.
Plenary: “Efficiency vs. Effectiveness: Recognizing the Difference for Low Income and First Generation Students” presented by Valerie Embry, director of the Academic Excellence Student Support Services Program.
– Wednesday, Nov. 14, 9 a.m., UMC Glenn Miller Ballroom.
Plenary: “Class, Race and Immigration in Higher Education” presented by CU-Boulder professors Melissa Hart and Ming Chen.
The educational and exploratory sessions highlight the research, talents and insights of faculty, students and staff and offer a view of diversity beyond the most common definitions. The event is hosted by the CU-Boulder Office of Diversity, Equity and Community Engagement, the Chancellor’s Advisory Committees and the city of Boulder.
The Diversity and Inclusion Summit shares the most current and up-to-date best practices around matters of diversity, inclusion, equity and social justice. As a public forum, the summit provides content to inspire new members of the campus community and to sustain veteran campus members toward a greater pluralistic campus, introduce everyday skills and practices for fostering an inclusive campus and work environment, and advance the skill set of long-term practitioners of diversity, inclusion and social justice.
A complete schedule of diversity summit events is available in the CU-Boulder Events Calendar at http://tinyurl.com/CUDiversitySummit2012.
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CU study: Nurture trumps nature in study of oral bacteria in human twins
0October 11, 2012
A new long-term study of human twins by University of Colorado Boulder researchers indicates the makeup of the population of bacteria bathing in their saliva is driven more by environmental factors than heritability.
The study compares saliva samples from identical and fraternal twins to see how much “bacterial communities” in saliva vary from mouth to mouth at different points in time, said study leader and CU-Boulder Professor Kenneth Krauter. The twin studies show that the environment, rather than a person’s genetic background, is more important in determining the types of microbes that live in the mouth.
Dr. Kenneth Krauter is the lead researcher on the project
For the new study, doctoral student Simone Stahringer sequenced the microbial DNA present in the saliva samples of twins. She and the research team then determined the microbes’ identities through comparison with a microbe sequence database. Saliva samples were gathered from twins over the course of a decade beginning in adolescence to see how salivary microbes change with time.
After determining the oral “microbiomes” of identical twins, who share the same environment and genes, and the microbiomes of fraternal twins who share only half their genes, the researchers found the salivary microbes of the identical twins were not significantly more similar to each other than to those of fraternal twins. “We concluded the human genome does not significantly affect which bacteria are living in a person’s mouth,” said Krauter of CU-Boulder’s molecular, cellular and developmental biology department. “It appears to be more of an environmental effect.”
Krauter said while the twin data from the oral microbiome study indicates that genetics plays a more minor role, it’s possible the genes still affect the oral microbiome in more subtle ways — an effect he plans to further explore.
Mouth bacteria. According to scientists, about 100 trillion microorganisms inhabit surfaces and cavities of our bodies,
A paper on the subject was published online Oct. 12 in the journal Genome Research. Other co-authors included doctoral student William Walters of MCD Biology, Jose Clemente and Rob Knight of the chemistry and biochemistry department, Robin Corley and John Hewitt of the Institute for Behavioral Genetics and Dan Knights, a former doctoral student in the computer science department.
The researchers also found that the salivary microbiome changed the most during early adolescence, between the ages of 12 and 17. This discovery suggests that hormones or lifestyle changes at this age might be important, according to the team.
Stahringer said that when several pairs of identical twins moved out of their homes and, for example, went off to college, the oral microbes they carried changed, which is consistent with the idea that the environment contributes to the types of microbes in the saliva. “We were intrigued to see that the microbiota of twin pairs became less similar once they moved apart from each other,” Stahringer said.
Krauter said there appears to be a core community of oral bacteria that is present in nearly all humans studied. “Though there are definitely differences among different people, there is a relatively high degree of sharing similar microbial species in all human mouths,” he said.
A DNA sequencing chart
The authors say the new study has established a framework for future studies of the factors that influence oral microbial communities. “With broad knowledge of the organisms we expect to find in mouths, we can now better understand how oral hygiene and environmental exposure to substances like alcohol, methamphetamines and even foods we eat affect the balance of microbes,” said Krauter.
The saliva samples used in the new study came from the university’s Longitudinal Twin Study and Colorado Adoption Project, which have involved hundreds of identical and fraternal twin pairs. Researchers also are analyzing additional frozen saliva samples collected during their studies for another project assessing possible relationships of oral bacteria to drug addiction, he said.
CU has a strong research focus on the human microbiome. In a 2011 study led by the Washington University School of Medicine and involving CU-Boulder, researchers found the diversity and abundance of gut microbes in animals varied depending on whether they were carnivores, omnivores or vegetarians. Knight is a member of a national research team funded by the Bill & Melinda Gates Foundation to look at the gut microbes of normal and malnourished infants and children around the world in search of novel microbial therapeutics.
In 2012, some 200 researchers from the NIH-funded Human Microbiome Project, including eight CU-Boulder researchers, mapped the microbial makeup of healthy humans for the first time. The study involved nearly 250 healthy U.S. volunteers and targeted 15 to 18 individual sites on the body harboring microbial communities.
Other recent studies involving CU researchers included one that found the delivery methods of babies have a big effect on their individual microbiomes, and second that showed women have a greater diversity of hand bacteria than men. Another showed personal bacterial communities living on the fingers and palms of individual computer users can be matched up with bacterial signatures on the computers and computer mice they recently used, a potential new tool for forensic scientists in the future.
According to scientists, about 100 trillion microorganisms inhabit surfaces and cavities of our bodies, which amounts to roughly 10 microbes per human cell.
Genome Research is an international, peer-reviewed journal that focuses on research that provides new insights into the genome biology of all organisms, including advances in genome medicine.
Funding for the study was provided by National Institutes of Health grants HD-010333 and DA-011015.
For more information on CU-Boulder’s MCD Biology department visit http://mcdb.colorado.edu/. For more information on Genome Research visit http://www.genome.org.
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New CU-Boulder study clarifies diversity, distribution of cutthroat trout in Colorado
0September 24, 2012
Will the real greenback cutthroat trout please stand up?
A novel genetic study led by the University of Colorado Boulder has helped to clarify the native diversity and distribution of cutthroat trout in Colorado, including the past and present haunts of the federally endangered greenback cutthroat trout.
The study, led by CU-Boulder postdoctoral researcher Jessica Metcalf, was based largely on DNA samples taken from cutthroat trout specimens preserved in ethanol in several U.S. museums around the country that were collected from around the state as far back as 150 years ago. The new study, in which Metcalf and her colleagues extracted mitochondrial DNA from fish to sequence genes of the individual specimens and compared them with modern-day cutthroat trout strains, produced some startling results.
The biggest surprise, said Metcalf, was that the cutthroat trout native to the South Platte River drainage appears to survive today only in a single population outside of its native range — in a small stream known as Bear Creek that actually is in the nearby Arkansas River drainage. The strain from Bear Creek is thought to have been collected from the South Platte River drainage in the 1880s by an early hotelier who stocked the fish in a pond at the Bear Creek headwaters to help promote an early tourist route up Pikes Peak.
“We thought one way to get to the question of which cutthroat trout strains are native to particular drainages was to go back to historical samples and use their DNA as a baseline of information,” said Metcalf of the chemistry and biochemistry department and a former postdoctoral researcher at the Australian Centre for Ancient DNA. “Our study indicates the descendants of the fish that were stocked into Bear Creek in the late 1800s are the last remaining representatives of the federally protected greenback cutthroat trout.”
A second, key set of data was all of the Colorado cutthroat trout stocking records over the past 150 years, a task spearheaded by study co-author and fish biologist Chris Kennedy of the U.S. Fish and Wildlife Service. Between 1889 and 1925, for example, the study showed that more than 50 million cutthroat trout from the Gunnison and Yampa river basins were stocked in tributaries of all major drainages in the state, jumbling the picture of native cutthroat strains in Colorado through time and space.
Originating from the Pacific Ocean, cutthroat trout are considered one of the most diverse fish species in North America and evolved into 14 recognized subspecies in western U.S. drainages over thousands of years. In Colorado, four lineages of cutthroats were previously identified: the greenback cutthroat, the Colorado River cutthroat, the Rio Grande cutthroat and the extinct yellowfin cutthroat.
The museum specimens used in the study came from the California Academy of Sciences, the Smithsonian Museum of Natural History in Washington, D.C., the Academy of Natural Sciences in Philadelphia and the Harvard University Museum of Comparative Zoology. Colorado cutthroat trout specimens were collected by a number of early naturalists, including Swiss scientist and former Harvard Professor Louis Agassiz and internationally known fish expert and founding Stanford University President David Starr Jordan.
The new study, published online today in Molecular Ecology, follows up on a 2007 study by Metcalf and her team that indicated there were several places on the Front Range where cutthroat populations thought to be greenbacks by fish biologists were actually a strain of cutthroats transplanted from Colorado’s Western Slope in the early 1900s.
CU graduate researcher, Sierra Stowell (pictured here as a teenager) was a co-author of the study. She spends a lot of time in or near the water where cutthroat trout live.
Other co-authors on the new study included CU-Boulder Professor Andrew Martin and CU-Boulder graduate students Sierra Stowell, Daniel McDonald and Kyle Keepers; Colorado Parks and Wildlife biologist Kevin Rogers; University of Adelaide scientists Alan Cooper and Jeremy Austin; and Janet Epp of Pisces Molecular LLC of Boulder.
“With the insight afforded by the historical data, we now know with a great deal of certainty what cutthroat trout strains were here in Colorado before greenbacks declined in the early 20th century,” said Martin of CU’s ecology and evolutionary biology department. “And we finally know what a greenback cutthroat trout really is.”
Metcalf and her colleagues first collected multiple samples of tissue and bone from each of the ethanol-pickled trout specimens, obtaining fragments of DNA that were amplified and then pieced together like a high-tech jigsaw puzzle to reveal two genes of the individual specimens. The tests were conducted on two different continents under highly sterile conditions and each DNA sequencing effort was repeated several times for many specimens to ensure accuracy in the study, Metcalf said.
Roughly half of the study was conducted at CU-Boulder and half at the Australian Center for Ancient DNA at the University of Adelaide, where Metcalf had worked for two years. “By conducting repeatable research at two very different, state-of-the-art laboratories, we were able to show the Bear Creek trout was the same strain as the cutthroats originally occupying the South Platte River drainage.”
The Bear Creek trout strain is now being propagated in the Colorado Parks and Wildlife hatchery system and at the USFWS Leadville National Fish Hatchery.
In addition to identifying the Bear Creek cutthroat trout, Metcalf and her colleagues discovered a previously unknown cutthroat strain native to the San Juan Basin in southwestern Colorado that has since gone extinct. The study also confirmed that the yellowfin cutthroat, a subspecies from the Arkansas River headwaters that grew to prodigious size in Twin Lakes near Leadville, also had gone extinct.
Fortunately, most fish preserved by naturalists before 1900 were “fixed” in ethanol, which makes it easier for researchers to obtain reliable DNA than from fish preserved in a formaldehyde solution, a practice that later became popular. Prior to the new study — which included DNA from specimens up to about 150 years old — scientists working in ancient DNA labs had only performed similar research on ethanol-preserved museum vertebrate specimens less than 100 years old.
“One of the exciting things to come from this research project is that it opens up the potential for scientists to sequence the genes of other fish, reptiles and amphibian specimens preserved in ethanol further back in time than ever before to answer ecological questions about past diversity and distribution,” said Metcalf, who conducts her research at CU’s BioFrontiers Institute.
Funding for the study was provided by agencies of the Greenback Cutthroat Trout Recovery Team, including the USFWS, the U.S. Forest Service, the Bureau of Land Management, the National Park Service and Trout Unlimited.
“I think in many cases success depends less on the application of a new technology and more on the convergence of people with shared interest and complementary skills necessary for solving difficult problems,” said Martin. “Our greenback story is really one about what can be discovered when dedicated and talented people collaborate with a shared purpose.”
“We’ve known for some time that the trout in Bear Creek were unique,” said Doug Krieger, senior aquatic biologist for Colorado Parks and Wildlife and the Greenback Cutthroat Trout Recovery Team leader. “But we didn’t realize they were the only surviving greenback population.”
The decline of native cutthroats in Colorado occurred because of a combination of pollution, overfishing and stocking of native and non-native species of trout, said Metcalf. “It’s ironic that stocking nearly drove the greenback cutthroat trout to extinction, and a particularly early stocking event actually saved it from extinction,” she said.
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CU study: Nitrogen damage to RMNP could become irreversible
0July 10, 2012
A new study led by the University of Colorado Boulder indicates air pollution in the form of nitrogen compounds emanating from power plants, automobiles and agriculture is changing the alpine vegetation in Rocky Mountain National Park.
The emissions of nitrogen compounds to the atmosphere are being carried to remote areas of the park, altering sensitive ecosystems, said CU-Boulder Professor William Bowman, who directs CU-Boulder’s Mountain Research Station west of Boulder and who led the study. “The changes are subtle, but important,” he said. “They represent a first step in a series of changes which may be relatively irreversible.”
A new study led by the University of Colorado Boulder indicates air pollution in the form of nitrogen compounds emanating from power plants, automobiles and agriculture is changing the alpine vegetation in Rocky Mountain National Park.
The emissions of nitrogen compounds to the atmosphere are being carried to remote areas of the park, altering sensitive ecosystems, said CU-Boulder Professor William Bowman, who directs CU-Boulder’s Mountain Research Station west of Boulder and who led the study. “The changes are subtle, but important,” he said. “They represent a first step in a series of changes which may be relatively irreversible.”
In other regions of the world, higher amounts of nitrogen pollutants correlate with decreased biodiversity, acidified soils and dead stream organisms like trout, said Bowman. “There is evidence that indicates once these changes occur, they can be difficult if not impossible to reverse. It is best to recognize these early stages before the more harmful later stages happen.”
The study site was an alpine meadow roughly one mile east of Chapin Pass in the Mummy Range of Rocky Mountain National Park. Bowman and his team analyzed the plant communities and soils under ambient levels of nitrogen deposition and compared them to plots with added nitrogen to simulate the increasing atmospheric nitrogen pollution expected in the coming decades. The results indicated changes in plant abundances already were occurring under ambient conditions, but to date no changes in soils were detected.
During the course of the three-year study, rising levels of nitrogen in the soils correlated with large increases in a common species of sedge shown to flourish in other nitrogen addition studies. Bowman said the team anticipates that the diversity of vascular plant species will rise with increasing nitrogen deposition, then decrease with more rare species being excluded by competition from other plant species. “While the changes are relatively modest, they portend that other more environmentally adverse impacts may be on the horizon in Colorado’s alpine areas,” said Bowman.
A paper on the subject was published in the June issue of the Journal of Environmental Management. Co-authors on the study included John Murgel, a former CU-Boulder undergraduate student now completing graduate work at Colorado State University, and Tamara Blett and Ellen Porter of the Air Resources Division of the National Park Service in Lakewood, Colo. The study was funded by the National Park Service.
Previous studies by Bowman and others have shown vegetation changes and soil acidification has been occurring due to increasing nitrogen deposition at other alpine sites in Colorado, including Niwot Ridge. Niwot Ridge is a National Science Foundation-funded Long-Term Ecological Research site administered by CU-Boulder and located adjacent to the university’s Mountain Research Station located some 30 miles west of the city.
Given the projected population growth in Front Range cities in the greater Denver area and increasing agricultural development, nitrogen deposition is expected to increase steadily in Rocky Mountain National Park over the next several decades, said Bowman, a professor in CU-Boulder’s ecology and evolutionary biology department.
The high-elevation ecosystems of the park are a magnet for thousands of visitors each year who have opportunities to see plants and animals well adapted to the severe climate above treeline, said Bowman, but such ecosystems are the most sensitive to adverse impacts from air pollutants. Previous studies by other researchers have documented ongoing changes in the algae found in several of the Rocky Mountain National Park’s high elevation lakes due to nitrogen pollution, he said.
While the park is also a haven for fishermen hoping to catch trout in pristine waters, continued inputs of nitrogen pollutants are a hazard to the health of both trout and their food sources, said Bowman, also a fellow of CU-Boulder’s Institute of Arctic and Alpine Research. It starts when the ability of the land plants and soils to take up the nitrogen is exceeded, causing soils to become acidified, he said.
Other parts of the Colorado Front Range have exhibited signs of acidification at the highest elevations, Bowman said. “Once this happens, soluble aluminum leaches from soils and begins to show up in streams and lakes. This aluminum is quite toxic to many aquatic animals,” he said.
“The take-home message is that the amount of nitrogen deposition reaching the tundra in Rocky Mountain National Park has already passed an important threshold and may lead to more serious environmental impacts,” said Bowman. “It’s not inconceivable that continued negative ecological impacts in the park due to nitrogen pollution could eventually impact tourism in Colorado.”
Officials from Environmental Defense and Trout Unlimited petitioned the State of Colorado and the Environmental Protection Agency to reduce emissions of nitrogen pollution in 2004. This effort resulted in a 2007 plan to lower nitrogen emissions on a voluntary basis to reduce impacts to Rocky Mountain National Park.
Excel Energy’s recent switch to natural gas in some of its power plants is one of many steps toward limiting nitrogen emissions, said Bowman. Ongoing efforts by air quality managers and representatives from the Colorado agricultural industry are also working on management practices that would lower nitrogen emissions.
In other regions of the world, higher amounts of nitrogen pollutants correlate with decreased biodiversity, acidified soils and dead stream organisms like trout, said Bowman. “There is evidence that indicates once these changes occur, they can be difficult if not impossible to reverse. It is best to recognize these early stages before the more harmful later stages happen.”
The study site was an alpine meadow roughly one mile east of Chapin Pass in the Mummy Range of Rocky Mountain National Park. Bowman and his team analyzed the plant communities and soils under ambient levels of nitrogen deposition and compared them to plots with added nitrogen to simulate the increasing atmospheric nitrogen pollution expected in the coming decades. The results indicated changes in plant abundances already were occurring under ambient conditions, but to date no changes in soils were detected.
During the course of the three-year study, rising levels of nitrogen in the soils correlated with large increases in a common species of sedge shown to flourish in other nitrogen addition studies. Bowman said the team anticipates that the diversity of vascular plant species will rise with increasing nitrogen deposition, then decrease with more rare species being excluded by competition from other plant species. “While the changes are relatively modest, they portend that other more environmentally adverse impacts may be on the horizon in Colorado’s alpine areas,” said Bowman.
A paper on the subject was published in the June issue of the Journal of Environmental Management. Co-authors on the study included John Murgel, a former CU-Boulder undergraduate student now completing graduate work at Colorado State University, and Tamara Blett and Ellen Porter of the Air Resources Division of the National Park Service in Lakewood, Colo. The study was funded by the National Park Service.
Previous studies by Bowman and others have shown vegetation changes and soil acidification has been occurring due to increasing nitrogen deposition at other alpine sites in Colorado, including Niwot Ridge. Niwot Ridge is a National Science Foundation-funded Long-Term Ecological Research site administered by CU-Boulder and located adjacent to the university’s Mountain Research Station located some 30 miles west of the city.
Given the projected population growth in Front Range cities in the greater Denver area and increasing agricultural development, nitrogen deposition is expected to increase steadily in Rocky Mountain National Park over the next several decades, said Bowman, a professor in CU-Boulder’s ecology and evolutionary biology department.
The high-elevation ecosystems of the park are a magnet for thousands of visitors each year who have opportunities to see plants and animals well adapted to the severe climate above treeline, said Bowman, but such ecosystems are the most sensitive to adverse impacts from air pollutants. Previous studies by other researchers have documented ongoing changes in the algae found in several of the Rocky Mountain National Park’s high elevation lakes due to nitrogen pollution, he said.
While the park is also a haven for fishermen hoping to catch trout in pristine waters, continued inputs of nitrogen pollutants are a hazard to the health of both trout and their food sources, said Bowman, also a fellow of CU-Boulder’s Institute of Arctic and Alpine Research. It starts when the ability of the land plants and soils to take up the nitrogen is exceeded, causing soils to become acidified, he said.
Other parts of the Colorado Front Range have exhibited signs of acidification at the highest elevations, Bowman said. “Once this happens, soluble aluminum leaches from soils and begins to show up in streams and lakes. This aluminum is quite toxic to many aquatic animals,” he said.
“The take-home message is that the amount of nitrogen deposition reaching the tundra in Rocky Mountain National Park has already passed an important threshold and may lead to more serious environmental impacts,” said Bowman. “It’s not inconceivable that continued negative ecological impacts in the park due to nitrogen pollution could eventually impact tourism in Colorado.”
Officials from Environmental Defense and Trout Unlimited petitioned the State of Colorado and the Environmental Protection Agency to reduce emissions of nitrogen pollution in 2004. This effort resulted in a 2007 plan to lower nitrogen emissions on a voluntary basis to reduce impacts to Rocky Mountain National Park.
Excel Energy’s recent switch to natural gas in some of its power plants is one of many steps toward limiting nitrogen emissions, said Bowman. Ongoing efforts by air quality managers and representatives from the Colorado agricultural industry are also working on management practices that would lower nitrogen emissions.
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Clothing still required at former nudie lake, however
0May 15, 2012
On-trail leash restrictions lifted at Coot Lake
Wetland closure still in effect
The temporary on-trail leash restrictions put in place for wildlife protection and nesting birds surrounding the wetland west of Coot Lake are lifted, as of Wednesday, May 16, 2012. While the wetland area itself remains closed to all activity, the trail is now under the standard Voice and Sight Control regulation. Violation of city of Boulder wildlife closure area may result in a summons by enforcement personnel.
At their March meeting, members of the Parks and Recreation Advisory Board recommended that staff review the status of the nesting season on May 15, and if no nesting activity was confirmed at Coot Lake, then the leash restrictions would be reviewed and potentially lifted.
As the season is still early for some species nesting such as American bitterns, monitoring reports have indicated that there have been few sightings of Northern harrier that also use wetlands as nesting areas. Staff and nearly 22 raptor monitor volunteers will continue to monitor this and other areas for potential nesting sites as the season progresses.
The Parks and Recreation Department wishes to thank the general public for compliance of wildlife related restrictions to help promote healthy and functioning habitat areas. Wetland habitat around the Boulder area supports a wide diversity of wildlife species as well as exceptional wildlife viewing opportunities throughout the year.
For more information, please contact Matt Claussen, urban resources manager, 303-413-7258.
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The future looks rosy for CU’s Safran and Johnson
0February 16, 2012
Two CU-Boulder faculty win National
Science Foundation CAREER Awards
Two University of Colorado Boulder faculty members, both from the ecology and evolutionary biology department, have received prestigious National Science Foundation Early Career Development, or CAREER, awards.
The awards, which went to assistant professors Pieter Johnson and Rebecca Safran, are made to outstanding faculty in the early stages of their careers who effectively integrate innovative research and educational outreach.
Johnson was awarded $700,000 over five years to study how ecological diversity in natural communities can affect disease risk for amphibians, which are the most threatened class of vertebrates worldwide. One significant reason for the decline of amphibians is their vulnerability to infections by parasitic flatworms called trematodes, which burrow into tadpoles and larval salamanders and cause limb malformations in adults, increasing mortality rates.
Johnson hopes to identify the factors that control disease in natural ecosystems and better understand the role of parasites in ecosystem processes. The complex life cycle of the parasitic trematodes allows them to move from snails into larval amphibians, which causes malformed legs in adult amphibians. These adult amphibians then are often eaten by predatory birds like herons, which pass eggs of the trematodes back into the aquatic environment where they hatch and enter snails to repeal the cycle.
Johnson will be collaborating with National Geographic to enhance a “Citizen Science” program that involves members of the public reporting on deformed amphibians they encounter. In addition, he will work with several other organizations to develop a documentary to promote awareness of the issue, and will team up with a biology textbook publisher to design an educational module that is expected to reach tens of thousands of students annually in classrooms and through online learning programs.
Safran was awarded $850,000 over five years to study genetic differences in barn swallow populations to gain a greater understanding of how new species are formed. The goal of the effort is to measure the genetic variation and gene flow related to the adaptive evolutionary changes within swallow populations — including different combinations of sexual signaling traits — as well as changes due to geographic isolation among different populations.
Safran and her team will use cutting-edge molecular approaches using genomics and stable isotope analysis in their research efforts. The team hopes to understand how migratory behavior, climate change, sexual selection and geographic distance between swallow populations relate to genetic divergence and speciation, which is the evolutionary process by which new species are created. The study will allow “evolution in action” to be carefully documented and studied, Safran said.
The research effort will include international collaborators from 35 Northern Hemisphere countries and will provide training for students at various levels of education and involve extensive interdisciplinary research. Her grant also includes a number of public outreach efforts including a “Citizen Science” program and a project in collaboration with EcoArts Connections of Boulder in which people are encouraged to ride Boulder County buses and to chart and report on various bird species seen from the vehicles.
Johnson also was awarded a five-year, $875,000 David and Lucille Packard Fellowship in 2008 to support his studies of emerging diseases in changing environments.
-CU-
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Boulder County cropland policy gets a “C” for compromise
0December 20, 2011
Commissioners adopt Boulder County Cropland Policy
Boulder County, Colo. – The Boulder County Board of Commissioners voted unanimously today to adopt the county Cropland Policy with some additional recommendations.
The policy, which has been under development throughout the last two years, includes the conditional approval of some genetically engineered crops. The approval includes corn, which has been allowed since 2003, and directs staff to develop protocols for the planting of sugar beets.
The additional recommendations will ensure that Roundup Ready crops are not planted year-after-year and maintain crop rotation to prevent herbicide-resistant weeds from developing on public lands. Additionally, a notification program will be established to inform Boulder County land managers and neighboring private farms and landowners when any new genetically engineered crop is to be planted on public land.
Statement from Commissioners Ben Pearlman, Cindy Domenico and Will Toor:
First and foremost we would like to thank the thousands of people who have been involved in the process of crafting this policy. From the staff and advisory group members who poured months of research into the process, to the input and comments we received from all segments of the community, we are most appreciative of this massive collective effort. Working on this policy has been one of the biggest challenges each of us has faced as elected officials, and also one of the most educational and worthwhile processes we have undertaken. It is important to note that 83 of the 86 recommendations included in the policy are universally accepted.
The Cropland Policy deals with agricultural land publicly owned by Boulder County. In other words, this policy affects only about 10 percent of the farms located in Boulder County and about 15 percent of the county’s cropland. We know that we must continue working with all public land farmers – conventional and organic – to farm this agricultural land, and farm it well, to increase local food production, prevent takeover by noxious weeds, and use best practices to preserve the land for future generations.
We have already implemented policies to promote agriculture on our public lands, including the application of lease revenues back into farming, supporting better infrastructure like improved water delivery systems and crop storage, and helping small-market and organic farmers get onto the land and become productive. We have also taken specific measures to increase organic farming on public land. This includes rent reduction for those transitioning to organic and funding the expansion of the Longmont farmers market.
We have worked steadily to train new farmers, particularly those interested in organic farms, and county open space land under organic production or transition has increased dramatically – from less than 150 acres in 2005 to more than 1,500 acres in 2012. That is 10 percent of our public cropland, or about 15 times the national average of .7 percent. However, even as we push toward increased organic, a large percentage of our land will be in conventional production for years to come
The Cropland Policy we have adopted provides more detail on how we will manage these resources in a balanced way into the future. In crafting this policy, we’ve heard loud and clear from the public that people want local food produced by local farmers that is healthy, grown with less pesticide, and that provides as much value as possible out of each crop. This leads us to highlight our need to diversify, to support a great variety of farms, crops and farmers. With 30 percent of Boulder County residents living at just 200 percent of the national poverty rate, we need make our local food system work for everyone in the most cost-effective way possible.
Following a thorough review process and meeting strict protocols, genetically modified field corn was approved as a crop on Open Space lands in 2003. Pollen drift studies for five years confirmed that the protocols were effective. No issues have been raised over that time by organic producers. 
Now, as tenant farmers have applied to plant genetically engineered sugar beets, we have looked even further into the issue. What we have seen locally as farmers have moved to genetically engineered corn and sugar beets are reductions in the toxicity and amount of pesticide and herbicide used, as well as reductions in erosion and runoff as farmers have been able to turn to strip tilling and low tilling practices. We have also seen significant increases in yield coupled with a decreasing carbon footprint resulting from fewer passes across the field to deliver pesticides and herbicides.
Farming is a struggle, as we have heard from each farmer we have visited. We cannot take tools away without replacing them with real options. We need to move forward, acknowledging agriculture’s complexity and celebrating its diversity. We know that Boulder County farmers have always used crop rotation as a best practice and that rotation will continue to benefit croplands by stifling the emergence herbicide-resistant weeds.
However, genetically modified crops come with downsides, and many people have expressed concerns about the crops’ food safety risks and impacts on human health. While additional study is necessary, science indicates that the health impact on humans is not likely to be significant and the risks associated with genetically modified foods are not likely to be higher than those associated with a variety of types of conventional breeding. With that in mind, we still believe that consumer choice is important and that people should have the ability to choose not to eat them. To that end, we strongly support labeling and will include this in the county’s federal legislative agenda.
We believe an outright ban of genetically engineered crops on our land is not the right direction to take. With appropriate safeguards, they can be a part of the overall mix of uses on cropland. Moreover, appropriate protocols for planting and managing these crops are absolutely necessary, including evaluating any future crops that become available based on their individual characteristics. In particular, we do not support the use of any additional glyphosate tolerant crops that would be in rotation with corn or sugar beets, as we do not support the use of Roundup on the same lands year after year.
We have always been about co-existence in Boulder County. Large and small farms sit side-by-side. Organic farmers and conventional farmers, on private and public land, work just over the fence line with respect for one another, neighbors working together. Farmers in Boulder County must pursue a variety of options in order to remain viable and if we want local food sources, we must allow local producers to grow crops that are profitable.
Most importantly, we believe that the changes we want to see on our cropland – the meaningful efforts to produce locally grown food for Boulder County markets– will occur as a result of our continued cooperation with local farmers. One thing that has been clear in this process is that a broad cross section of the community supports the goal of increasing local food production for local consumption. The county is committed to working with the farmers, with the local natural foods industry, and with other stakeholders to expand the local food system.
Again, we want to say how much we appreciate the large number of residents and members of the farming community who contributed to the lively and informational debate that influenced and guided our decisions.
-BoulderCounty.org-
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CU study: Lowly worms survive asteroid wipeout
0October 10, 2011
A new study of sediments laid down shortly after an asteroid plowed into the Gulf of Mexico 65.5 million years ago, an event that is linked to widespread global extinctions including the demise of big dinosaurs, suggests that lowly worms may have been the first fauna to show themselves following the global catastrophe.While the focus on the so-called K-T boundary extinction is often on the survival and proliferation of mammals, paleo-botanical studies show some of the earliest terrestrial ecosystems to emerge were dominated by low-diversity and opportunistic aquatic plants, said University of Colorado Boulder geological sciences Associate Professor Karen Chin. And while sediments laid down immediately following the impact event generally have relatively few animal fossils, new evidence from North Dakota shows networks of crisscrossing burrows less than three inches above the K-T boundary layer.
“Fossil burrows provide direct evidence of animal activity that occurred right at that spot, and these burrows are quite extensive,” said Chin, who said their characteristics suggest they were probably produced by worms. “To my knowledge, such burrows haven’t been documented in terrestrial environments this close to the K-T boundary. This is a glimpse of a world we don’t know very much about yet.”
While Chin and her colleagues are still working to understand the timing of the fossil burrows as they relate to the K-T extinction boundary, Chin said she believes that they likely were made within a few thousand years after the extinction event. Future studies should help narrow that window, said Chin, who also is curator of paleontology at the University of Colorado Museum of Natural History.
Chin gave a presentation on the new findings at the 2011 annual meeting of the Geological Society of America being held this week in Minneapolis. Co-authors on the study were A.A. Ekdale of the University of Utah and Dean Pearson of the Pioneer Trails Regional Museum in Bowman, N.D.
The three-dimensional burrows were found at the interface of a layer of coal and a layer of siltstone in southwestern North Dakota by Pearson, who has spent many years studying K-T boundary sites in the state. The decomposing organic matter in the ancient environment would have provided a food source for the worms. A few of the burrows were topped by a thin layer of coal, suggesting that the underlying coal may contain additional, earlier worm burrows that are not readily apparent, Chin said.
The clay boundary layer laid down at the end of the Cretaceous Period is associated with high levels of iridium, an element rare in Earth’s crust but abundant in asteroids. The Manhattan-sized asteroid plowed into Earth at 150 times the speed of a jet airliner and is thought to have released about a billion times more energy than the Hiroshima atomic bomb, triggering tremendous dust and ash storms, wildfires, tsunamis, mega-earthquakes and dark, cold “nuclear winter” conditions for a time.
The North Dakota fossil worm burrows indicate the creatures probably were about the diameter of an average earthworm. The burrows indicate horizontal rather than vertical movement through the substrate, likely reflecting feeding activity, Chin said.
The study indicates the burrows were made in a peat-producing, bog-like environment that eventually was buried by sediment. Chin said the worms must have been capable of withstanding the challenging environmental stresses of flooded habitats, including prolonged inundation, low oxygen and acidic conditions.
Since the ancient burrows were filled by sediment, they actually are “positive casts” of the trails made by the worms. The burrows are examples of “trace fossils,” which also include tracks and fossilized feces, or coprolites. “When we reconstruct past environments, soft-bodied animals like worms get short-shrift since they don’t stand out in the fossil record like animals with mineralized skeletons,” said Chin. Ekdale, an expert on trace fossils, was key in analyzing the worm burrows, Chin said.
Chin said extensive work on plant fossils both before and after the K-T boundary event by Denver Museum of Nature and Science Chief Curator Kirk Johnson and his colleagues helped Chin and her research team to characterize the environment inhabited by the burrowers. Johnson’s research helped establish that terrestrial plants suffered heavy losses during the K-T extinction event, as did non-avian dinosaurs and many other terrestrial and marine organisms.
The K-T boundary commonly refers to the dividing line between the Cretaceous and Tertiary periods. Geologists now refer to it as the Cretaceous-Paleogene, or K-Pg boundary event. While a number of vertebrates survived the event — including birds, snakes, lizards, turtles, fish and small mammals — fossil burrows provide direct evidence of animal activity that skeletal fossils cannot show, said Chin. “The fact that the burrows are so close to the K-T boundary is one reason they are so exciting.”
-CU-
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Philip P. DiStefano, Chancellor University of Colorado Boulder writes in:
0September 23, 2011
From the Chancellor
S E P T E M B E R 2 0 1 1
Dear Friends,
 Philip P. DiStefano |
As another fall semester at CU-Boulder begins, I am pleased to report that numbers from our fall student census are in and CU-Boulder has enrolled the most diverse freshman class in our history. The 1,141 diverse students in our freshman class, based on race and ethnicity, constitute a full 20 percent of the freshman class and brings our overall diversity at CU-Boulder to 17 percent. We increased both our resident students (by eight percent) and non-resident students (by 12 percent), and we are making gains in enrolling new populations.
 The class of 2015 catches the Buff spirit at Student Convocation just prior to the start of fall classes. |
Consider, for example, that one in five freshmen is a first-generation student. We’ve also increased international freshmen by 50 percent (129 students), enhancing the opportunity for all students to gain a global perspective in the classroom, while increasing transfer students by 12 percent. This rich diversity proves that CU-Boulder is truly a highly desired destination for students not only from Colorado, but also from around the nation, and the world.
 Thomas Cech, Nobel Laureate and professor of chemistry and biochemistry, works with research specialist Elaine Podell. |
$359 million in sponsored research revenue garnered in 2011
Our faculty and their staff attracted $359 million in federally sponsored research revenues in fiscal 2011. The awards are for research ranging from biomedicine and sustainable energy advances to environmental studies and space research such as planetary exploration. We also were federally funded to design and build spacecraft and instruments to study near-Earth space weather events that impact satellites, power grids, and ground communications systems.
While sponsored research awards do not support university operating expenses, they are reinvested in the local economy in the form of wages, supplies and equipment to the tune of $1 billion over the last four years. These funds also translate into cutting-edge instruction in the classroom involving 1,000 undergraduates and 1,150 graduate students participating in research.
The following list shows the diversity and reputation of our research by funding agency and percentage of our awards: National Science Foundation (24%), NASA (22%), Departments of Commerce and Health and Human Services (18% each), Department of Energy (7%), Department of Defense (6%) and other federal agencies (5%).
 Law students Adria Robinson and Dave Digiacomo discuss constitutional law with South High School students in Denver. |
CU-Boulder’s value to our graduates and the state
A new survey by Payscale.com shows that a CU-Boulder degree continues to be highly rated for mid-career earning power. We pride ourselves in that ranking as well as in our students’ values, like our No. 1 ranking in Peace Corps participation, our 13,000 students who work in community service annually and our student-led sustainability initiatives.
Value can be looked at in another way: our value to the state of Colorado and its citizens in fueling the state economy. In an environment of shrinking state and federal support, we must be entrepreneurial in moving forward both the university and the state we serve. One way we do that is when our faculty and students help to stoke the economy through transfer of technology into the marketplace, which our faculty are doing to an unprecedented degree, initiating seven new companies in the last year alone.
 Elementary students gather in Fiske Planetarium to talk with astronaut Mike Fossum on the International Space Station. |
And finally, our reach into Colorado’s K-12 schools provides value in the education and enlightenment of students. To celebrate Constitution Day last week, the CU Law School launched a new program sending 60 law students to 50 high schools to lead one-period discussions on the First Amendment in classrooms from Adams County to Carbondale. In theater, the Colorado Shakespeare Festival troupe is taking a production of “Twelfth Night” to 25 elementary, middle and high schools from Fort Collins to Trinidad to offer a lesson on bullying. “Twelfth Night” actors will lead a discussion after each performance in a collaboration with our Center for the Study and Prevention of Violence.
Channel 9, Sept. 20: Astronaut, children connect across thousands of miles
 Chancellor DiStefano congratulates a rider at the finish line of the Buffalo Bicycle Classic Sept. 11. |
Buffalo Bicycle Classic raises over $200,000 in scholarship money
More than 1,850 riders raised more than $200,000 for scholarships Sept. 11 at the Elevations Credit Union Buffalo Bicycle Classic. The ride has generated 548 scholarships totaling $1.4 million for academically strong students who need financial support. Students cannot apply for the scholarship and don’t even know they’re in the running until they learn they have won. The event was founded in 2003 by CU supporter Woody Eaton and Arts and Sciences Dean Todd Gleeson.
Speaking of Dean Todd Gleeson, he announced Aug. 24 that he will return to the classroom as a professor in the integrative physiology department and resign as dean of the College of Arts and Sciences next year following a highly successful decade of leading the college. Todd’s creativity, exemplified by the Buffalo Bicycle Classic fundraiser, is a key reason the college is stronger than ever, including a more than doubling of the college’s endowment. I will make a decision on a search later this academic year, but I want to thank Todd for his outstanding service to the university as a visionary and able administrator in the roles of dean and associate dean over the last 14 years.
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Welcoming our Pac-12 peers If you come into town for Family Weekend and the Pac-12 opener next week you will likely notice street banners welcoming our visiting conference partners and their fans. We are excited to have this illustrious group of world-renowned universities as peers and we look forward to continuing our many research partnerships with the likes of Stanford, Cal, Washington, UCLA and Arizona, as well as with all the other outstanding members of the Pac-12.Our Pac-12 hospitality has already been singled out by Cal fans who came to town Sept. 10 and who are still raving on their fan site “The Bear Insider” about the welcoming fans, the sportsmanship at Folsom Field, and the beautiful Boulder campus. One of my favorite quotes was, “After Saturday I have to say that the CU fans are the best in their treatment of visitors. Everyone we talked to was nice and helpful. I got the feeling CU fans are happy to be in the Pac-12 and showed it before, during and after the game.”Families joining us for Family Weekend also are invited next Friday to Faculty Convocation, a special recognition of our world-class faculty where we will honor their achievements and celebrate 53 new faculty members this year. This special event is hosted in Old Main, the university’s first building. I am proud that CU-Boulder’s faculty has more than 50 prestigious National Academy members, seven MacArthur fellows and four Nobel Prize winners to its credit.Sincerely,
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NEW CU-BOULDER STUDY REVEALS BACTERIA FROM DOG FECES IN OUTDOOR AIR OF URBANIZED AREAS
0August 18, 2011
NEW CU-BOULDER STUDY REVEALS BACTERIA FROM DOG FECES IN OUTDOOR AIR OF URBANIZED AREAS
Bacteria from fecal material — in particular, dog fecal material — may constitute the dominant source of airborne bacteria in Cleveland’s and Detroit’s wintertime air, says a new University of Colorado Boulder study.
The CU-Boulder study showed that of the four Midwestern cities in the experiment, two cities had significant quantities of fecal bacteria in the atmosphere — with dog feces being the most likely source.
“We found unexpectedly high bacterial diversity in all of our samples, but to our surprise the airborne bacterial communities of Detroit and Cleveland most closely resembled those communities found in dog poop,” said lead author Robert Bowers, a graduate student in CU-Boulder’s ecology and evolutionary biology department and the CU-headquartered Cooperative Institute for Research in Environmental Sciences, or CIRES. “This suggests that dog poop may be a potential source of bacteria to the atmosphere at these locations.”
The study was published July 29 in Applied and Environmental Microbiology. Co-authors on the study included Noah Fierer, an assistant professor in CU-Boulder’s ecology and evolutionary biology department and a CIRES fellow; Rob Knight, an associate professor in CU-Boulder’s chemistry and biochemistry department; Amy Sullivan and Jeff Collett Jr. of Colorado State University; and Elizabeth Costello of the Stanford University School of Medicine.
Scientists already knew that bacteria exist in the atmosphere and that these bacteria can have detrimental effects on human health, triggering allergic asthma and seasonal allergies, Fierer said. But it is only in recent years that researchers have realized that there is an incredible diversity of bacteriaresiding in the air, he said.
“There is a real knowledge gap,” said Fierer. “We are just starting to realize this uncharted microbial diversity in the air — a place where you wouldn’t exactly expect microbes to be living.”
To gain further understanding of just what microbes are circulating in urban environments, the team analyzed the local atmosphere in the summer and winter at four locations in the Great Lakes region of the U.S. Three of the locations — Chicago, Cleveland and Detroit — are major cities with populations of greater than 2 million, and one location, Mayville, Wis., is a small town with a population of less than 6,000.
The team used nearly 100 air samples collected as part of a previous study conducted by Colorado State University. The CSU experiment investigated the impact of biomass burning and involved studying the impacts of residential wood burning and prescribed fires on airborne fine particle concentrations in the midwestern United States.
“What we’ve been looking at are the numbers and the types of bacteria in the atmosphere,” Fierer said. “We breathe in bacteria every minute we are outside, and some of these bugs may have potential health implications.”
The researchers analyzed the bacteria’s DNA in the collected air samples and compared the bacteria they found against a database of bacteria from known sources such as leaf surfaces, soil, and human, cow and dog feces. They discovered that the bacterial communities in the air were surprisingly diverse and also that, in two of the four locations, dog feces were a greater than expected source of bacteria in the atmosphere in the winter.
In the summer, airborne bacteria come from many sources including soil, dust, leafsurfaces, lakes and oceans, Bowers said. But in the winter, as leaves drop and snow covers the ground, the influence that these environments have as sources also goes down. It is during this season that the airborne communities appeared to be more influenced by dog feces than the other sources tested in the experiment, he said.
“As best as we can tell, dog feces are the only explanation for these results,” Fierer said. “But we do need to do more research.”
The team plans to investigate the bacterial communities in other cities and to build a continental-scale atlas of airborne bacterial communities, Fierer said. “We don’t know if the patterns we observed in those sites are unique to those cities,” he said. “Does San Francisco have the same bacteria as New York? Nobody knows as yet.”
Fierer believes it is important to pin down the types of bacteria in the air, how these bacteria vary by location and season, and where they are coming from.With this information, scientists can then investigate the possible impacts on human health, he said.
“We need much better information on what sources of bacteria we are breathing in every time we go outside,” Fierer said.
The study was funded by the CIRES Innovative Research Program, the U.S.
Environmental Protection Agency, the National Science Foundation, the Howard Hughes Medical Institute and the National Institutes of Health. The aerosol sample collection for this project was supported by the Lake Michigan Air Directors Consortium.
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One-of-a-kind, natural surface bike park to open June 11 in Boulder
0June 6, 2011
Media interview opportunities available in advance of Valmont Bike Park grand opening
What do you call 40 acres of twisting trails, mild to wild dirt, structural jumps, strategically-placed sand pits, logs, boulders and staircases? While off-road cyclists may soon call it, “Shangri La,” we call it, “Valmont Bike Park.”
Opening for the first time at 9 a.m. Saturday, June 11, the City of Boulder Parks and Recreation Department’s latest park development has already been hailed as an outstanding bike park by the International Mountain Biking Association (IMBA).
“Cyclists from around the nation will be totally floored by what they see,” said IMBA Executive Director Mike Van Abel. “Based on its many options for riding natural-surface trails, the diversity of both technical and non-technical features and the outstanding quality of the build, Valmont will be among the top venues in the country for this style of biking.”
The City of Boulder’s Parks and Recreation Department will open the newly-developed park with a grand opening event from 9 a.m. to 4 p.m. on Saturday, June 11. The event will feature an official ribbon-cutting ceremony at 10 a.m. with comments from council members, including Deputy Mayor Ken Wilson and Parks and Recreation Director Kirk Kincannon. Food and bicycle gear vendors, a cycling demonstration (on the park’s slopestyle features) and public riding in the park will round out the day’s activities. The event is free and open to the community.
The park contains a pump track, dual slalom and slopestyle riding loop as well as elements for a competition cyclo-cross course. The park also includes training and skill building trails, a toddler playground, event plaza, restrooms, parking and outstanding city and Flatiron views. Developed with the support and partnership of the local cycling community, Boulder Mountainbike Alliance (BMA) and organizations such as the PLAY Boulder Parks Foundation and Great Outdoors Colorado, the 40-acre Valmont Bike Park encompasses natural-surface amenities for multiple riding styles and skill levels.
“We are very excited to open this flagship park,” Kincannon said. “We invested in a collaborative partnership with BMA and the off-road cycling community to design and build this portion of Valmont City Park. The result is a park worthy of our internationally-recognized athletic community—one that will be a daily asset to local kids, families, riders and businesses and also attract events and riders from all over the country and the world.”
Note to Media: Media interviews with Parks and Recreation Department Director Kirk W. Kincannon will be available on a scheduled basis on June 7 and 8. The media is encouraged to attend the grand opening event on June 11. Please contact Shelly Ruspakka by June 7 at RuspakkaS@BoulderColorado.gov or 303-413-7214 to set up a media interview or to discuss plans for the opening event.
The bike park is currently closed due to allow completion of construction. The park will open to cycling on June 11. No footage of park use or demonstrations will be available until June 11.
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MAJORITY OF CU-BOULDER STUDENTS REPORT POSITIVE CAMPUS EXPERIENCE, ACCORDING TO SOCIAL CLIMATE SURVEY
0June 1, 2011
In an extensive survey of the University of Colorado Boulder’s nearly 30,000 students, overwhelming majorities of respondents had an approving view of the campus’s social climate — the extent to which CU-Boulder makes students feel welcome, valued and supported. Around four in five respondents reported feeling intellectually stimulated often or very often. A similar proportion said they felt welcome and accepted, and nearly nine in ten said they felt comfortable in their classes.
The survey, done in fall 2010, was the latest edition of CU-Boulder’s Social Climate Survey, conducted about every four years since 1994 by the university’s Office of Planning, Budget and Analysis, or PBA. The online survey was sent to 29,926 degree-seeking undergraduate and graduate students, and completed by 7,777, or 26 percent.
The favorable view of CU-Boulder’s social climate was generally shared by all subgroups studied — men and women, undergraduate and graduate students, students in all of the university’s schools and colleges, politically liberal and conservative students, students in fraternities and sororities, students who are the first in their family to attend college, gay and straight students, students from all socioeconomic backgrounds, students of different races and ethnicities, students with physical or psychological disabilities, nontraditional-age students, students who entered as freshmen and transfers, international students, students affiliated with the military, and students with different religious affiliations, including Catholics, other Christians, Jews, Muslims, Buddhists and nonbelievers. Membership in these self-identified subgroups was determined using survey responses provided by the students.
Overall, students described the campus as friendly and welcoming, with 80 percent of both undergraduate and graduate students reporting feeling welcome and accepted either often or very often. Eighty-eight percent said they feel comfortable in their classes, and 80 percent reported feeling intellectually stimulated. Large majorities described CU-Boulder as “accepting of diverse perspectives” in the classroom, 81 percent, and outside the classroom, 63 percent.
On a broad measure of feeling welcome and comfortable on campus and in the Boulder community, students who self-identified in diverse subgroups generally reported a positive experience — averaging about 4 on the 5-point scale. Although the positive assessment of the campus’s social climate was shared across all subgroups, two subgroups of at least 100 respondents did rate it slightly lower — around 3.5 — African-American students and students who characterized themselves as having a psychological or psychiatric disability such as depression or post-traumatic stress disorder. Their ratings were, however, still above the scale midpoint of 3.0. There was also a tendency for slightly less positive evaluations of the campus social climate by GLBT students, nontraditional-age students, students of lower socioeconomic status, very liberal students, very conservative students, students not affiliated with a fraternity or sorority, transfer students, and students affiliated with the Buddhist and Muslim faiths. Their ratings were, nevertheless, well above the neutral point on the scale.
Comprising 149 scaled questions, plus another six open-ended questions, the survey collected a massive amount of information — over a million responses to the ratings, and nearly 23,000 written comments, amounting to half a million words. The thousands of student comments include praise for particular classes that addressed diversity issues, suggestions to increase enrollment of international students and to make tuition more affordable for low-income students, reports of uncomfortable situations involving derogatory comments about women or gays or people of color, descriptions of personal experiences with religious or political prejudice, and accounts of situations that led to better understanding between people of different backgrounds. One student wrote, “Thanks for continuing to educate people on these issues, I feel like a much bigger and better person since I came to CU.”
Differences in survey results across 2001, 2006 and 2010 indicate an overall trend of small but consistent and wide-ranging improvements in the social climate on the CU-Boulder campus. For example, students’ level of comfort taking part in campus social life was higher in 2010, as were the average levels of feeling welcome, accepted, supported and intellectually stimulated at CU-Boulder. In all three surveys, African-American undergraduate students perceived the climate at CU-Boulder somewhat less favorably than did undergraduates of other races/ethnicities. Compared with 2001 and 2006, however, African-American undergraduates in 2010 reported feeling more welcome on the Boulder campus and more comfortable participating in campus social life and life on the Hill. Other students also reported feeling more welcome and comfortable in 2010.
A campus advisory board representing a wide range of campus units helped guide the survey and data analysis, including the assistant vice chancellor for diversity, equity and community engagement, the associate vice chancellor for undergraduate education, faculty, and representatives from student government, Disability Services, the GLBT Resource Center, Religious Campus Organizations, Wardenburg Health Center, the Office of Orientation, the Center for Multicultural Affairs and the Women’s Resource Center.
The survey’s findings are used primarily to evaluate, revise and develop programs and policies that promote student success by helping all students feel like valued members of the university community. PBA and members of the survey’s advisory board have been working together to distribute the results and encourage their use throughout the university community.
“For several years, the Office of Diversity, Equity and Community Engagement has worked with several campus community committees to assess and maintain the social climate for all students, especially as it impacts learning in and outside the classroom, as well as staff and faculty,” said Alphonse Keasley, assistant vice chancellor for diversity and equity. “The results of the latest survey will be most instructive in the ways that various Chancellor Advisory Committees can continue to recommend diversity and inclusion needs to ODECE and senior level administrators that are central to the campus’s mission and purpose.”
The results will also be used by academic affairs. “The Office of Undergraduate Education will be using specific results of this campus climate survey to fine tune or modify specific programs which have a significant focus on improving the welcoming climate we want for our students,” said Michael Grant, associate vice chancellor for undergraduate education. “For example, our McNeil, Daniels, Ethnic Living and Learning and Academic Excellence programs, among others, all work with students who may find understanding and fitting into a research university environment a particular challenge for it is often a really new and different cultural environment. This is also the case for many international students.”
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GUT MICROBES IN HUMANS AND OTHER MAMMALS HEAVILY INFLUENCED BY DIET, SAYS NEW STUDY C U Boulder
0May 20, 2011
by Boulder Channel 1
in News
You are what you eat whether you’re a lion, a giraffe or a human — at least in terms of the bacteria in your gut.
A new study led by the Washington University School of Medicine and involving the University of Colorado Boulder shows gut microbial communities in humans and in a wildly diverse collection of mammals carry out core physiological functions that are heavily influenced by whether they are carnivores, herbivores or omnivores.
The researchers sequenced intestinal microbes in stool samples from 33 mammalian species living in the wild or in zoos in St. Louis and San Diego. In addition to identifying the bacterial species living in the mammalian intestines, they characterized the pool of genes present in each microbial community and their related functions, said senior study author Dr. Jeffrey Gordon of the Washington University School of Medicine in St. Louis.
CU-Boulder professor and study co-author Rob Knight said despite the wide variation of mammals selected for the study, the different gut microbial communities share a set of standard metabolic functions common to all species that play a key role in digestion and immune health. Understanding the variation in human microbial intestine communities holds promise for future clinical research, said Knight, a faculty member in the chemistry and biochemistry department and the computer science department.
A paper on the subject was published in the May 20 issue of Science. Other co-authors on the study included CU-Boulder’s Justin Kuczynski, Dan Knights, Jose Clemente and Antonio Gonzalez, Washington University School of Medicine’s Brian Muegge and Luigi Fontana, and Bernard Henrissat of the Archictecture et Fonction des Macromolecules Biologiques in Marseille, France.
“This was the first time we were able to relate the microbial community members to the specific metabolic functions that were being performed,” said Knight, who also is a Howard Hughes Medical Institute Early Career Scientist. “This is surprising because even members of the same bacterial species can have genomes that are up to 40 percent different in terms of gene content.”
The team extracted DNA from the mammals and humans and used powerful computer methods to sort gene fragments and match them to the DNA of known organisms.
While there was considerable variation of bacterial gut communities between animals, the study showed many of the same microbial genes were found in all of the digestive tracts, with differences in their relative abundance dependent on whether they were meat-eaters, vegetarians or omnivores. Among the mammals whose fecal material was used to sequence gut bacteria microbes included giraffe, bighorn sheep, gazelle, kangaroo, hyena, lion, polar bear, elephant, gorilla, baboon, black bear and squirrel.
The team also showed how diet influences microbial communities in the human gut by sampling 18 lean people who purposely had cut their caloric intake by 25 percent or more using many different dietary strategies. The researchers found that the functions of gut microbes varied according to how much protein the individuals ate, and the bacterial species varied according to how much fiber was consumed.
In a related 2009 study led by CU-Boulder’s Knight, researchers developed the first atlas of microbial diversity across the human body, charting wide variations in microbe populations from the forehead and feet to noses and navels of individuals. One goal of human bacterial studies is to find out what is normal for healthy people, which should provide a baseline for studies looking at human disease states, said Knight, who also is a fellow at CU’s Colorado Initiative for Molecular Biotechnology.
“If we can better understand this microbial variation, we may be able to begin searching for genetic biomarkers for disease,” said Knight. It might someday be possible to identify sites on the human body, including the gut, that would be amenable to microbial community transplants with either natural or engineered microbial systems that would be beneficial to the health of the host, he said.
“Because the human microbiome is much more variable than the human genome, and because it also is much easier to modify, it provides a much more logical starting point for personalized medicine,” he said.
The latest findings emphasize the need to sample humans across the globe with a variety of extreme lifestyles and diets, including hunter-gatherer groups, said the researchers. Such studies could provide insight into the limits of gut bacteria variation and the possibility that human microbes co-evolved with human bodies and cultures, shaping our physiological differences and environmental adaptations.
Members of Knight’s lab and their many collaborators are studying how the human microbiome — all of a person’s hereditary information — is assembled in different people and how it varies in conditions such as obesity, malnutrition and Crohn’s disease. In addition to financial support from HHMI, Knight also has been supported by National Institutes of Health funds to develop new computational tools to better understand the composition and dynamics of microbial communities.
The Science magazine study was supported by the NIH and the Crohn’s and Colitis Foundation of America.
-CU-
Related posts:
Food Trucks Rule : by Rob Smoke
0April 27, 2011
by Boulder Channel 1
in News
Rob Smoke is a city side columnist for Boulder Channel 1 news
Food Trucks Rule
Not being completely informed on the topic, I googled “food trucks” and also “food truck rules and regulations” –
TONS of interesting material
Why in the world does Boulder want to effectively prohibit or discourage new food truck businesses?
It can’t be that the local restaurant industry objects, because if they are objecting, they are merely being stupidly reflexive.
The diversity of food choices that food trucks provide make them potential attractions to a neighborhood or event –
thus, even though they might compete with brick and mortar restaurants, they are still desirable neighbors,
particularly if we are talking about trucks bearing some culinary distinction.
In some places, the trucks are only disallowed via objection by a neighboring restaurant, thus it seems
illogical to demand that trucks simply not be located near one.
In some locales food trucks have ridiculous regulations, but in other places those rules are being revamped and redesigned to
encourage this type of business. Food trucks can make unique offerings — cuisine not otherwise found in the city –
if the rules and regulations are such to discourage anyone who might take a shot, you’d think the city would take a closer look at
what rules are actually necessary regarding health and safety issues, and then go a little easier on the broader parameters that
make it either possible or impossible to do business —
if you have a blanket rule against trucks being located near a brick and mortar establishment, you’re making up a rule
that other cities with successful food truck businesses don’t have –
and for what exactly?
I’m trying to comprehend, but alas…
my comments go either unread or unheeded…with no response from anyone except for one person on council who says they disagree –
yikes!!!
