UC Davis News: Environmental Sciences

California's Ancient Kelp Forest

Tue, 10 Nov 2009 00:00:00 -0800

The kelp forests off southern California are considered to be some of the most diverse and productive ecosystems on the planet, yet a new study indicates that today's kelp beds are less extensive and lush than those in the recent past.

The kelp forest tripled in size from the peak of glaciation 20,000 years ago to about 7,500 years ago, then shrank by up to 70 percent to present day levels, according to the study by Rick Grosberg, professor in the Department of Evolution and Ecology and the Center for Population Biology at UC Davis, with Michael Graham of the Moss Landing Marine Laboratory and Brian Kinlan at UC Santa Barbara.

Kelp forests around offshore islands peaked around 13,500 years ago as rising sea levels created new habitat and then declined to present day levels. The kelp along the mainland coast peaked around 5,000 years later.

This transition from an extensive island-based kelp system to a mainland-dominated system coincided with conspicuous events in the archaeological record of the maritime people in the region, suggesting that climate-driven shifts in kelp ecosystems impacted human populations that used those resources.

Understanding the past history of a population is crucial to understanding its genetics in the present, Grosberg said.

"Kelp is interesting because it disperses only over short distances," Grosberg said. "Populations can become genetically isolated from one another even if they are quite close together."

"We wanted to know how connected the coastal kelp populations were since the last glacial maximum," he said.

On land, scientists can reconstruct the history of a forest or grassland from fossilized pollen or leaves. But kelp do not make pollen, and marine sediments do not preserve a good record of the plants.

The researchers used depth charts of the southern California coastline and information from sediment cores on past nutrient availability to reconstruct potential kelp habitat as sea levels changed over the last 20,000 years.

"We could reconstruct changes in kelp cover at a scale of 500 years and determine how fragmented or connected the populations were," Grosberg said.

People have lived off the produce of kelp forests when resources on land dwindled, and those changes are recorded in shell middens and other traces. That archaeological record can now be compared with the ecological history to get a more complete picture of California's coast.

"Now we know what was happening with kelp, what was happening with the ecology on land, and what the people were doing," Grosberg said.

The study was published online Oct. 21 in the journal Proceedings of the Royal Society B.

Electronic Waste Needs to Go Green

Tue, 10 Nov 2009 00:00:00 -0800

Americans love their consumer electronics, but what happens to all the gadgets when their useful life is over? Despite being one of the largest generators of "e-waste" in the world, the U.S. has no federal policies on recycling electronic waste or handling hazardous materials from technological trash.

It's time to change that, argue four University of California scientists in an article in the Oct. 30 issue of the journal Science. The authors point out that electronic junk from the U.S. is not just a domestic problem, but a global one.

Devices such as cell phones and computers contain both valuable materials, such as gold and silver, and hazardous ones, such as lead, cadmium and other heavy metals. Efforts to recover the former in rudimentary recycling centers in developing countries can release the latter, with devastating consequences.

"The U.S. is way behind in this area compared to Europe and even parts of Asia," said Julie Schoenung, professor of chemical engineering and materials science at UC Davis and one of the authors of the article with three colleagues at UC Irvine: Oladele Ogunseitan, professor of health sciences; Jean-Daniel Saphores, associate professor of civil and environmental engineering; and Andrew Shapiro, an associate adjunct professor of electrical engineering and computer science.

A few states, including California, have strict rules and recycling mandates. But manufacturers face a patchwork of state regulation across the country. In the European Union, by contrast, there are longstanding directives that govern electronics recycling, based on the concept of "extended producer responsibility." The manufacturer of a product is responsible for ensuring that the product is properly recycled when its useful life is over. With strong recycling mandates, a flourishing recycling industry has grown up.

China has recently passed laws to encourage electronics recycling and ensure that it is done properly, Schoenung said.

Without clear recycling options, many U.S. consumers may simply put that old phone in a drawer and forget about it. Schoenung and her colleagues recently estimated that there are as many as 1.5 million tons of electronic waste sitting in homes and garages across the U.S.

A new act now before the U.S. Senate attempts to address the problem. The Electronic Device Recycling Research and Development Act would fund research and demonstration projects, education efforts and research into alternatives to toxic or hazardous materials.

The bill also calls for e-waste education targeted to undergraduate engineering students, but engineers also need to learn from other disciplines such as toxicologists, ecologists and economists, Schoenung said. Educational efforts should include graduate programs, where there are greater opportunities for interdisciplinary work, she said.

"The recognition by Congress is important, but we are maybe starting a little too far back in doing research and analysis," Schoenung said. There is much that can already be learned from the European experience, she said.

Cave Study Links Climate Change to California Droughts

Tue, 10 Nov 2009 00:00:00 -0800

California experienced centuries-long droughts in the past 20,000 years that coincided with the thawing of ice caps in the Arctic, according to a new study by UC Davis doctoral student Jessica Oster and geology professor Isabel Montañez.

The finding, which comes from analyzing stalagmites from Moaning Cavern in the central Sierra Nevada, was published online Nov. 5 in the journal Earth and Planetary Science Letters.

The sometimes spectacular mineral formations in caves such as Moaning Cavern and Black Chasm build up over centuries as water drips from the cave roof. Those drops of water pick up trace chemicals in their path through air, soil and rocks, and deposit the chemicals in the stalagmite.

"They're like tree rings made out of rock," Montañez said. "These are the only climate records of this type for California for this period when past global warming was occurring."

At the end of the last ice age about 15,000 years ago, climate records from Greenland show a warm period called the Bolling-Allerod period. Oster and Montanez's results show that at the same time, California became much drier. Episodes of relative cooling in the Arctic records, including the Younger Dryas period 13,000 years ago, were accompanied by wetter periods in California.

The researchers don't know exactly what connects Arctic temperatures to precipitation over California. However, climate models developed by others suggest that when Arctic sea ice disappears, the jet stream -- high-altitude winds with a profound influence on climate -- shifts north, moving precipitation away from California.

"If there is a connection to Arctic sea ice then there are big implications for us in California," Montañez said. Arctic sea ice has declined by about 3 percent a year over the past three decades, and some forecasts predict an ice-free Arctic ocean as soon as 2020.

Oster's analysis of the past is rooted in a thorough understanding of the cave in the present. Working with the cave owners, she has measured drip rates, collected air, water, soil and vegetation samples, and studied what happens to the cave through wet and dry seasons to determine how stalagmites are affected by changing conditions.

Oster collected stalagmites and cut tiny samples from them for analysis. The ratio of uranium to its breakdown product, thorium, allowed her to date the layers within the stalagmite. Isotopes of oxygen, carbon and strontium and levels of metals in the cave minerals all vary as the climate gets wetter or drier.

"Most respond to precipitation in some way," Oster said. For example, carbon isotopes reflect the amount of vegetation on the ground over the cave. Other minerals tend to decrease when rainfall is high and water moves through the aquifer more rapidly.

Oxygen-18 isotopes vary with both temperature and rainfall. Measuring the other mineral compositions provides more certainty that the changes primarily track relative rainfall.

The stalagmite records allowed Oster and Montañez to follow relative changes in precipitation in the western Sierra Nevada with a resolution of less than a century.

"We can't quantify precipitation, but we can see a relative shift from wetter to drier conditions with each episode of warming in the northern polar region," Montañez said.

Other authors on the paper are Warren Sharp, a geochronologist at the Berkeley Geochronology Center, and Kari Cooper, associate professor of geology at UC Davis. The research was funded by the National Science Foundation.

About UC Davis

For 100 years, UC Davis has engaged in teaching, research and public service that matter to California and transform the world. Located close to the state capital, UC Davis has 31,000 students, an annual research budget that exceeds $500 million, a comprehensive health system and 13 specialized research centers. The university offers interdisciplinary graduate study and more than 100 undergraduate majors in four colleges — Agricultural and Environmental Sciences, Biological Sciences, Engineering, and Letters and Science — and advanced degrees from six professional schools — Education, Law, Management, Medicine, Veterinary Medicine and the Betty Irene Moore School of Nursing.

Earth and Physical Sciences Building Dedicated

Mon, 02 Nov 2009 00:00:00 -0800

Nov. 5, Thursday, 3:30 p.m. -- California Assemblywoman Alyson Huber (D-El Dorado Hills) will join UC Davis Chancellor Linda Katehi, Winston Ko, dean of the Division of Mathematical and Physical Sciences, and guests to dedicate the new Earth and Physical Sciences Building on campus. The three-story $65.5 million building comprises 90,000 gross square feet and will provide a new home for the Department of Geology, as well as teaching laboratories and facilities for the departments of Geology, Chemistry and Physics.

Planning is now under way for a new GATEways (Gardens, Arts and The Environment) earth sciences garden that will link the building with the adjacent arboretum. The garden will be an outdoor geological laboratory for student learning and public outreach. The theme of the garden will be "Assembling California," after the 1993 book by John McPhee that chronicled 15 years of field trips with Eldridge Moores, an emeritus professor of geology at UC Davis.

The building was designed by Perkins+Will, a Chicago-based commercial architect design firm, and built by Flintco, a commercial contractor headquartered in Tulsa, Okla. The project was financed primarily through state funds.

Please note that apart from news media, this is an invitation-only event.

Federal Stimulus Funds to UC Davis Will Bring 250 Jobs

Fri, 30 Oct 2009 00:00:00 -0700

Federal stimulus grants to UC Davis will put some 250 people to work on earthquake safety, new sources of clean energy and West Nile virus control, among dozens of other research projects. So far 53 of the jobs are in place, with the rest expected to come on line in the near future.

UC Davis job numbers were announced today as part of a national report from the White House on initial outcomes from the 2009 American Recovery and Reinvestment Act, and are based on an analysis of $69.9 million in stimulus awards the campus had received as of Sept. 30. Overall, UC Davis has submitted more than $500 million in proposals for stimulus funds.

According to the White House report, awards to UC Davis have generated 53 full-time-equivalent positions on campus, ranging from lab technicians to professors.

At least 200 additional employees will be required to carry out research projects funded by the stimulus awards, campus officials say. Further job-creation numbers will be reported to the federal government at the end of the year.

"In addition to creating and preserving jobs in a difficult economy, these grants will support important research in medicine, basic sciences and engineering that will have long-term benefits for the economy of California and the nation -- and they will help us to train the next generation of scientists," said Barry Klein, vice chancellor for research at UC Davis.

"Moreover, we are optimistic that discoveries made in the course of stimulus-funded research will create new enterprises and additional long-term, sustainable jobs," Klein said.

Signed into law by President Obama in February, the American Recovery and Reinvestment Act charged the National Institutes of Health and National Science Foundation with distributing $11.2 billion in stimulus funds to scientists around the country.

The program is intended to save or create more than 3.5 million jobs nationwide over the course of two years, while helping to revitalize the nation's scientific research enterprise.

According to information available online from federal agencies that administer research funding, UC Davis faculty had received 176 stimulus grants worth $69.9 million as of Sept. 30. The projects include:

* $2.3 million to study the spread of tuberculosis, which kills some 1.7 million people worldwide each year

* $2 million to develop a new, more powerful electron microscope

* $1.5 million to the Clinical and Translational Science Center, which focuses on bringing promising medical research to the bedside

* $780,000 for research on building foundations that can withstand earthquakes

* $685,000 for cardiovascular research

* $548,000 for tools for predicting outbreaks of West Nile virus

* $490,000 to study the use of ultrasound in cancer treatment

* $478,000 for influenza virus studies

* $379,000 to explore causes of autism

* $378,000 for engineering and implanting replacement knee joint tissue

* $330,000 for technology that could lead to new materials for storing data

* $240,000 for research on cobalt water-splitting catalysts, a possible source of clean energy

* $206,000 to explore use of virtual reality technology for social-skills training of children with autism

Stimulus funds also are helping to fund a summer program to bring high school and college students, and teachers from schools at all levels, to university labs to learn about stem cells. Stimulus funds also help to pay graduate students studying for doctoral and master's degrees in science or engineering at UC Davis.

Stimulus funds have significantly boosted research funding the campus receives from established government and philanthropic channels. Support from external sources has more than doubled from $299 million in 2000-01 to $622 million for the 2008-09 fiscal year.

The stimulus program requires quarterly reporting by grant recipients of estimated jobs created. For the first quarterly report, due Sept. 30, UC Davis used payroll records to calculate jobs supported by stimulus funds. That calculation yielded an estimate of 53 full-time-equivalent positions in place. The estimate of an additional 200 jobs is based on analysis of the budgets of awards received, many of which have not yet shown up in the payroll system.

"The payroll count method is transparent, verifiable and accurate, while the budget estimate gives a realistic picture of the expected job count from funds received to date," Klein said.

He noted, however, that calculation methods are not yet uniform nationally, or even within the University of California system.

About UC Davis

For 100 years, UC Davis has engaged in teaching, research and public service that matter to California and transform the world. Located close to the state capital, UC Davis has 31,000 students, an annual research budget that exceeds $500 million, a comprehensive health system and 13 specialized research centers. The university offers interdisciplinary graduate study and more than 100 undergraduate majors in four colleges -- Agricultural and Environmental Sciences, Biological Sciences, Engineering, and Letters and Science -- and advanced degrees from six professional schools -- Education, Law, Management, Medicine, Veterinary Medicine and the Betty Irene Moore School of Nursing.

UC Davis Leads Bird Rescue in San Francisco Oil Spill

Fri, 30 Oct 2009 00:00:00 -0700

UC Davis wildlife experts are on the scene of an oil spill today in San Francisco Bay.

UC Davis veterinarian Michael Ziccardi, an international authority on the rescue and treatment of oiled wildlife, said staffers from the UC Davis Wildlife Health Center and its partner organizations are in boats at the Dubai Star oil spill to assess the situation and collect any oiled birds they find.

If oiled birds are eventually captured, they will be taken either to Oiled Wildlife Care Network member organizations in the San Francisco Bay Area or to a customized rescue trailer -- a traveling emergency room that can be towed from Davis to the spill command post. There, veterinary staffers will assess their condition and give them first aid.

The Oiled Wildlife Care Network is managed statewide by the UC Davis Wildlife Health Center, a unit of the UC Davis School of Veterinary Medicine.

Once assessed, the birds will be taken to the San Francisco Bay Oiled Wildlife Care and Education Center in Fairfield, where they will receive the world's most advanced veterinary care for oiled wildlife.

At the center, the first order of business is not to remove oil from the birds. Instead, it is to warm the birds and nourish them. Once stabilized, they will be better able to withstand the stresses of being washed.

The Fairfield center is a 12,000-square-foot, $2.7 million facility capable of caring for up to 1,000 sick birds. It is the major Northern California rescue center in the statewide Oiled Wildlife Care Network, which comprises 12 rescue facilities and 25 organizations prepared to care for oiled wildlife on short notice.

Because of an algae bloom earlier this month off the Oregon coast, the Fairfield center already houses 450 sick birds being cared for by the International Bird Rescue Research Center. Ziccardi said, however, that it can handle whatever oiled birds are affected during this spill and if needed, he will send the Oregon birds to sister facilities elsewhere in California.

At each California rescue center, UC Davis wildlife veterinarians work in partnership with local, trained wildlife rehabilitators. At the Fairfield center, those rehabilitators are staff members of the International Bird Rescue Research Center, Lindsay Wildlife Museum, WildCare and the Department of Fish and Game.

At this time, on Friday morning, a corps of trained volunteers is standing by to staff the rescue center, if needed.

Later, if more volunteers are needed, a notice will be posted online at http://www.vetmed.ucdavis.edu/owcn/.

Jonna Mazet, another UC Davis veterinarian and oiled-bird expert, has estimated that for every oiled seabird that is found washed ashore, an estimated 10 to 100 birds died at sea.

The Oiled Wildlife Care Network is managed statewide by the UC Davis Wildlife Health Center, a unit of the UC Davis School of Veterinary Medicine.

The Oiled Wildlife Care Network is funded by the California Office of Spill Prevention and Response, a unit of the Department of Fish and Game. The Fish and Game monies come from interest on the $50 million California Oil Spill Response Trust Fund, built from assessments on the oil industry.

The mission of the Oiled Wildlife Care Network is to ensure that wildlife exposed to petroleum products receive the best possible capture and care by ensuring a rapid response, coordinating effective emergency care in a spill crisis and administering an ongoing research program.

In addition to giving veterinary care, the network conducts and funds basic research into the effects of oil on wildlife and applied research into treatments that will improve survival.

About UC Davis

For 100 years, UC Davis has engaged in teaching, research and public service that matter to California and transform the world. Located close to the state capital, UC Davis has 31,000 students, an annual research budget that exceeds $500 million, a comprehensive health system and 13 specialized research centers. The university offers interdisciplinary graduate study and more than 100 undergraduate majors in four colleges -- Agricultural and Environmental Sciences, Biological Sciences, Engineering, and Letters and Science -- and advanced degrees from six professional schools -- Education, Law, Management, Medicine, Veterinary Medicine and the Betty Irene Moore School of Nursing.

Law School Hosts 'Cleantech' Symposium

Mon, 26 Oct 2009 00:00:00 -0700

Nov. 6, Friday -- Top professionals, entrepreneurs and executives in law, engineering and environmental sciences will explore the future of "cleantech" -- alternative energy and a broad range of other environmentally sensitive innovations -- during a daylong symposium at the UC Davis School of Law.

The symposium, entitled “CleanTech in the New ‘Environmental’ Environment,” will be held from 9 a.m. to 6 p.m. in the Wilkins Moot Courtroom in King Hall. Lunch will be served at the Walter A. Buehler Alumni and Visitors Center. All panel discussions are free and open to the public. The luncheon is $15 for students and $25 for others. To reserve a seat, register by Oct. 28 at http://www.law.ucdavis.edu/news/events/fenwickwest/cleantech-program.html.

Industry watchers hail cleantech as the “next big thing.” The emerging industry was one of the largest recipients of venture capital last year. President Obama has pledged to invest $150 billion over 10 years to establish a green energy sector capable of creating millions of new jobs.

Speakers will address developments in the entrepreneurial environment and the expanding role of universities and governments in providing financial, regulatory and technological support for the cleantech industry. They also will discuss how society, businesses and governments ranging from the Obama administration to key states and foreign countries are moving rapidly to develop green economies. Panelists will include:

• John Doerr, general partner, Kleiner Perkins Caufield & Byers, a leading venture capital firm; director of Google, Amazon.com and several private companies; and appointee to President Obama’s Economic Recovery Advisory Board. Doerr is one of the keynote speakers.
• Daniel Sperling, UC Davis professor of civil engineering and environmental science and policy; founding director of the Institute of Transportation Studies at UC Davis; and acting director of the UC Davis Energy Efficiency Center. Sperling also is a keynote speaker.
• Peter F. Ward, alternative fuel and vehicle technology program manager, California Energy Commission
• Erik Stenehjem, director, Industrial Partnerships Office, Lawrence Livermore National Laboratory
• Bill Tucker, executive director, Office of Technology Transfer, University of California Office of the President
• Peter Van Deventer, president and CEO, SynapSense
• Hal La Flash, director, Emerging Clean Technologies, Pacific Gas & Electric
• Paul Holland, partner, Foundation Capital, and board member, Serious Materials

The cleantech symposium is the second in a five-year Technology, Entrepreneurship, Science and Law lecture series co-sponsored by the UC Davis School of Law and Fenwick & West, a law firm serving technology and life sciences clients through offices in Mountain View, San Francisco and Seattle.

About UC Davis

For 100 years, UC Davis has engaged in teaching, research and public service that matter to California and transform the world. Located close to the state capital, UC Davis has 31,000 students, an annual research budget that exceeds $500 million, a comprehensive health system and 13 specialized research centers. The university offers interdisciplinary graduate study and more than 100 undergraduate majors in four colleges -- Agricultural and Environmental Sciences, Biological Sciences, Engineering, and Letters and Science -- and advanced degrees from six professional schools -- Education, Law, Management, Medicine, Veterinary Medicine and the Betty Irene Moore School of Nursing.

Explore the Emergent Universe

Tue, 29 Sep 2009 00:00:00 -0700

Ranging from slime molds to quantum matter to Alzheimer's disease, a new online exhibit opening Oct. 1 aims to encourage young people to learn about "emergence," complex behaviors that arise from the interaction of simple parts, and encourages them to develop an "emergent perspective."

"An emergent perspective allows you to approach real-world problems in a different way," said David Pines, distinguished professor of physics at UC Davis and co-director of the University of California Institute for Complex Adaptive Matter, which sponsored the Emergent Universe Web site. "You realize that here are no unique solutions -- you have to try many different things, look for organizing principles and get a feel for what is connected to what."

Emergent Universe http://www.emergentuniverse.org uses animations, art, games, music and even a manga comic book to draw viewers into exploring emergent phenomena. The exhibit is aimed at 15- to 30-year-olds, college-bound or college-educated, but not necessarily with a scientific background.

"Different activities are designed to appeal to a broad range of learning styles and interests," said designer and museum director, Suzi Tucker. "We chose to go for exploration, to let people get sucked in."

"We want to convey the idea that emergence is not just about studying emergent behavior in matter -- there are general principles that apply in the world at large, to climate change, to economics, to fixing our schools," Pines said.

"The idea is to introduce young people to the concept of emergence and encourage them to think about it in their daily life," he said.

A major part of the exhibit explores the "Fibril Connection": a misfolded amyloid protein can give rise to devastating conditions like Alzheimer's disease, yet the same proteins perform useful functions in other living systems. Visitors can zoom in on a human brain and discover the mysteries of amyloid through lab notebooks, animations and games.

In the "Unlocking the Universe" section, visitors can:
• Listen to music composed to express the concepts of emergence in quantum mechanics;
• View a manga comic that illustrates an emergent perspective;
• Zoom in on a pointillist image that illustrates length scales;
• Play the "Game of Life," creating patterns from simple interactions; and
• "Grow Art," from repeated application of very simple rules.

The developers plan to add a new section on superconductivity in the next year.

The site was designed and developed by Tucker, a former chemistry professor at UC Davis, with interactive designer Stephen Hartzog and scientific input from Pines, UC Davis physics professor Daniel Cox, and other members of the Institute for Complex Adaptive Matter. The site was funded mainly by the institute, a multidisciplinary research program of the University of California with 57 branches across the U.S. and globally, headquartered at UC Davis, with additional support from private foundations, the National Science Foundation and individual donors.

Bugs in Boxes Shed Light on Biological Invasions

Fri, 18 Sep 2009 00:00:00 -0700

Bugs in boxes are helping UC Davis researcher Alan Hastings improve scientific tools used to predict the spread of invasive plants and animals.

In today's edition of the journal Science, Hastings and a University of Colorado colleague report their latest findings from both a tightly controlled laboratory experiment and a mathematical model: When they released 600 identical beetles and let them spread at will through 30 identical landscapes over 13 generations, there was a surprising degree of difference in the outcome.

Some of the beetles went far and fast, traveling across 31 landscape patches in the 15-month experiment, while others went only a third as far. The rest fell somewhere in the middle.

Hastings said the results suggest that it won't be as easy as some had hoped to catalog all the factors that influence the spread of an invasion.

If it is difficult to predict the course of an invasion, it will be difficult to control it. And there are hundreds of destructive invaders in the U.S. alone, from kudzu to zebra mussels to the light brown apple moth.

"There appears to be this intrinsic variability, even in the simplest ecological settings, that means that difficulty in prediction is a basic feature of ecological systems," said Hastings, a professor in the UC Davis Department of Environmental Science and Policy.

Hastings is currently a principal investigator or co-investigator on four grants totaling more than $1 million. These studies range from researching the dynamics of salmon and cod populations to species' response to global climate change.

Hastings' collaborator and co-author Brett Melbourne was previously a postdoctoral scholar at UC Davis, and is now an assistant professor in the Department of Ecology and Evolutionary Biology at the University of Colorado, Boulder.

If invasion forecasts are to improve, Melbourne said, ecologists will have to keep trying to quantify the randomness in environmental and biological processes. "Ecological forecasts will become more like weather forecasts, with a stated range of probability but not certainty, like when the meteorologist says there is a 75 percent chance of rain on Thursday."

The study, "Highly Variable Spread Rates in Replicated Biological Invasions: Fundamental Limits to Predictability," is online at http://www.sciencemag.org/cgi/content/abstract/325/5947/1536.

It was funded by the National Science Foundation.

About UC Davis

For 100 years, UC Davis has engaged in teaching, research and public service that matter to California and transform the world. Located close to the state capital, UC Davis has 31,000 students, an annual research budget that exceeds $500 million, a comprehensive health system and 13 specialized research centers. The university offers interdisciplinary graduate study and more than 100 undergraduate majors in four colleges -- Agricultural and Environmental Sciences, Biological Sciences, Engineering, and Letters and Science -- and advanced degrees from six professional schools -- Education, Law, Management, Medicine, Veterinary Medicine and the Betty Irene Moore School of Nursing.

Annual Tahoe Report Says Asian Clam Invasion Is Growing Fast

Tue, 18 Aug 2009 00:00:00 -0700

Released today, UC Davis' annual Lake Tahoe health report describes a spreading Asian clam population that could put sharp shells and rotting algae on the spectacular mountain lake's popular beaches, possibly aid an invasion of quagga and zebra mussels, and even affect lake clarity and ecology.

"Our collaborative UC Davis and University of Nevada, Reno, science team found up to 3,000 Asian clams per square meter at locations between Zephyr Point and Elk Point in the southeastern portion of the lake," said John Reuter, associate director of the UC Davis Tahoe Environmental Research Center.

"Those are high numbers, especially when compared to the few isolated, dead shells we found back in 2002 when the Asian clam was first reported. We already see associated environmental effects from the clams today, and we are concerned that they might spread.”

Issued annually since 2007, the "Tahoe: State of the Lake Report" is intended to give the public a better understanding of the changes occurring in Lake Tahoe on a year-to-year basis and to place current conditions within a historical perspective. It summarizes tens of thousands of scientific observations of lake weather, water conditions and aquatic life made since 1900. It is compiled by the research scientists of the UC Davis Tahoe Environmental Research Center.

The dime-sized Asian clam (Corbicula fluminea) that is the researchers’ top concern this year probably has been in the lake for only 10 years, but it is already replacing native pea clams in lake sediments. In the areas where they are most numerous, Asian clams comprise almost half of the benthic, or sediment-dwelling, organisms, the report says.

What's more, in the beds of Asian clams, a green filamentous alga, Zygnema, is thriving. The report says the algae probably are being nourished by the high concentrations of nutrients excreted by the clams. Dead Zygnema clumps become a nuisance when they wash onto beaches and decompose. “This moves Lake Tahoe further away from its desired pristine condition,” Reuter said.

Another worry: UC Davis and UNR researchers say accumulations of Asian clams might foster the invasion of two other damaging species: quagga and zebra mussels, which radically alter ecosystems by consuming enormous amounts of the tiny algae that are the base of lake food chains and outcompeting the native bottom-dwelling species. The mussels are also feared for their ability to encrust piers and boat hulls, and have already caused millions of dollars in damage in the Great Lakes by blocking intake pipes at water and power plants.

Zebra and quagga mussels are spreading west by hitchhiking on boat hulls, and a comprehensive program of public education and boat inspections has been established by resource managers to try to keep them out of Lake Tahoe. While Asian clams are not expected to become the colonizing monster that quagga and zebra mussels are, they may make lake waters more hospitable to the problem mussels by concentrating calcium, an essential nutrient.

In addition to the Asian clam concerns, many other trends and observations are described in the 64-page State of the Lake Report. They include:

The lake’s clarity was unchanged from the previous year: The Secchi depth was 69.6 feet.
The long-term warming trend seen since 1970 continued, with warmer nights and lake waters, fewer cold days and less precipitation falling as snow. However, 2008 was a cold year, with the greatest number of freezing days since the early 1990s.
It was another dry year -- the 12th driest year on record. While the historical average annual precipitation is 31.6 inches, in 2008 only 19.3 inches of precipitation fell.
In 2008, Lake Tahoe mixed all the way to the bottom at the mid-lake station. This was the second successive year of deep mixing. Complete mixing during two or more successive years has only occurred three times since 1973. Mixing matters because it circulates nutrients and other material from the lake’s depths to the surface water and returns oxygen to the deep water.

The "Tahoe: State of the Lake Report 2009" is free and available online at http://terc.ucdavis.edu.

About the Tahoe Environmental Research Center

The Tahoe Environmental Research Center (TERC) is dedicated to research, education and public outreach on lakes and their surrounding watersheds and airsheds. Lake ecosystems include the physical, biogeochemical and human environments, and the interactions among them. The center is committed to providing objective scientific information for restoration and sustainable use of the Lake Tahoe Basin.

About UC Davis

UC Davis Challenge Produces a Better Air Conditioner

Thu, 13 Aug 2009 00:00:00 -0700

The first certified winner of the UC Davis “Western Cooling Challenge” is Coolerado Corp. of Denver. Recent federal tests showed that their five-ton commercial rooftop unit should be able to air-condition a typical big-box store with less than half the energy needed by conventional cooling units.

"Coolerado's entry in the Western Cooling Challenge was the first to take our rigorous tests at the Advanced HVAC Lab at the U.S. Department of Energy’s National Renewable Energy Laboratory in Golden, Colo.," said Mark Modera, director of the UC Davis Western Cooling Efficiency Center.

"We are extremely pleased to announce that Coolerado's product exceeded our expectations. While our target was a 40 percent reduction in energy use and peak electricity demand compared to conventional cooling units, the Coolerado H-80 tests indicate almost 80 percent energy-use savings and over 60 percent peak-demand reduction."

Launched in June 2008, the UC Davis Western Cooling Challenge is a program of activities designed to help cooling-unit manufacturers deliver better products, and to help building owners install and use those products in their new and existing low-rise, nonresidential buildings (such as suburban retail and office buildings).

Many western states are hot and dry, but use cooling systems that were designed for warm and humid climates. The Cooling Challenge is based on the premise that Western-specific technologies should be able to cool using far less energy.

The potential energy savings are substantial, Modera said: Commercial rooftop air-conditioning units are used to cool 70 percent of the floor area in nonresidential buildings in the western U.S.

Coolerado CEO Mike Luby said his company's five-ton H-80 rooftop unit is designed principally for light commercial buildings. One H-80 is able to cool 1,500 to 3,000 square feet of commercial floor area.

"Coolerado would not have taken on the big task of producing this exceptional product had it not been for the challenge laid down by the Western Cooling Efficiency Center,” Luby said.

The firm is now taking H-80 orders for delivery late this year. Luby said, “There will be a higher first cost associated with this equipment, but with utility rebates, tax incentives and energy savings, our customers should make up that difference in just two years."

The completed certification of the first unit puts the Western Cooling Challenge right on schedule to have a selection of new equipment reach the market by spring of 2010, Modera said.

Five other manufacturers have promised to submit equipment for Western-Cooling-Challenge efficiency testing. More results should be available by the end of 2009.

About the Western Cooling Efficiency Center

The Western Cooling Efficiency Center is a key component of the UC Davis Energy Efficiency Center (EEC), which was founded in 2006 with support from the California Clean Energy Fund (CalCEF). The cooling center is supported by industry affiliates, including utilities, manufacturers, contractors and the California Energy Commission. Its mission is to partner with stakeholders to identify technologies, disseminate information and implement programs that reduce cooling-system electrical demand and energy consumption in the Western United States. http://wcec.ucdavis.edu/

About Coolerado Corp.

Coolerado Corporation produces and sells very high-efficiency air conditioners, based in large part on indirect evaporative cooling. Coolerado air conditioners are used for commercial, industrial and residential applications throughout the world. http://www.coolerado.com

About UC Davis

'Clunkers' Program Is Expensive Way to Cut Carbon Emissions

Thu, 13 Aug 2009 00:00:00 -0700

New UC Davis estimates say the federal government's Cash for Clunkers program is paying at least 10 times the "sticker price" to reduce emissions of the greenhouse gas carbon dioxide.

While carbon credits are projected to sell in the U.S. for about $28 per ton (today's price in Europe was $20), even the best-case calculation of the cost of the clunkers rebate is $237 per ton, said UC Davis transportation economist Christopher Knittel.

"When burned, a gallon of gasoline creates roughly 20 pounds of carbon dioxide. I combined that known value with an average rebate of $4,200 and a range of assumptions about the fuel economy of the new vehicles purchased and how long the clunkers would have been on the road if not for the program," Knittel said. "I even assumed drivers didn't change their habits, although some analysts have suggested that the owners of new vehicles will drive more than they would have with their old cars.

"In the end, the lowest cost to remove one ton of carbon from the environment was $237. More likely scenarios produced a cost of more than $500 per ton, even when we accounted for reductions in pollutants other than greenhouse gases. That suggests the Cash for Clunkers program is an expensive way to reduce carbon."

Knittel did not analyze the program's other key objectives: stimulating the economy and providing relief for automobile manufacturers.

Knittel is an associate professor and chancellor's fellow in the UC Davis Department of Economics, a faculty associate at the UC Davis Institute of Transportation Studies, and the policy and business strategy leader of the Sustainable Transportation Energy Pathways Program at UC Davis.

His analysis, titled "The Implied Cost of Carbon Dioxide Under the Cash for Clunkers Program," was published online today (Aug. 13) by the University of California Energy Institute. It was funded by the Energy Institute and the Institute of Transportation Studies.