2008 - Marine Biological Laboratory
Transcription
2008 - Marine Biological Laboratory
MBL Biological Discovery in Woods Hole The Ecosystems Center Report 2008 Cover photo: Haystacks on the salt marsh in Newbury, Massachusetts. Salt marsh haying has been carried out since colonial times in the Plum Island Ecosystem. The marsh grasses are cut, then piled on wooden “staddles” to dry out before being sold. The hay is still valued as mulch for gardens. (Robert Buchsbaum) The Ecosystems Center MBL 7 MBL Street Woods Hole, Massachusetts 02543 http://www.ecosystems.mbl.edu Editors: Hugh W. Ducklow and Deborah G. Scanlon Designer: Beth Ready Liles The Ecosystems Center was founded in 1975 as a year-round research center of the MBL. Its mission is to investigate the structure and functioning of ecological systems, predict their response to changing environmental conditions, apply the resulting knowledge to the preservation and management of natural resources, and educate both future scientists and concerned citizens. E cosystems Center scientists work together on projects, and collaborate with investigators from other centers at the MBL and from other institutions, combining expertise from a wide range of disciplines. Together, they conduct research to answer a variety of scientific questions: At the Toolik Lake Arctic Long-Term Ecological Research (LTER) site on Alaska’s North Slope and at research sites in Greenland and northern Scandinavia, Ecosystems Center scientists study the effect of warmer temperatures on Arctic ecosystems. Will increased permafrost thaw make more nutrients available to plants? If these nutrients flow into streams and lakes, how will they affect the aquatic food web? At the Plum Island Ecosystems LTER site in northern Massachusetts, researchers ask how urban development affects the flow of nutrients and organic matter into New England estuaries. How will they alter the food web and plant growth in salt marshes? What happens to the production of commercially valuable fish as a result? Above: Adrian Rocha and Gus Shaver set up flux towers to measure carbon dioxide, water and energy exchange on tundra burned in extensive fires in Alaska. (Jim Laundre) Right, top: Ecosystems Center staff members construct a hoophouse to be used to over-winter trees and sagebrush that Ecosystems Center senior scientist Zoe Cardon uses in her research exploring interactions between plant roots and microbes in soils. (Zoe Cardon) Background: The Kuparuk River in Alaska in January. (Jonathan Benstead) In Boston Harbor, researchers measure the transfer of nitrogen from the sediments to the water column. How long will it take the harbor to recover from decades of sewage pollution? In the Arctic rivers of Eurasia, center scientists have conducted research that shows increased freshwater discharge. If ocean circulation is affected, how might the climate in western Europe and eastern North America change? On Martha’s Vineyard, researchers restore coastal sandplain ecosystems with either controlled burning or mechanical clearing. How much will beneficial processes such as groundwater recharge and nitrogen retention increase in restored ecosystems? Will it restore diversity in plant and animal species? At the Palmer Station LTER in Antarctica, Ecosystems Center scientists study the coastal ecosystem along the west Antarctic Peninsula, where sea ice duration has declined by 80 days in response to climate warming since 1975, leading to large-scale declines in animal populations and other changes in the marine ecosystem. Do these changes suggest the fate of other polar regions on the Antarctic continent? At the Harvard Forest LTER in central Massachusetts and at the Abisko Scientific Research Station in Sweden, scientists use soilwarming experiments to assess how forests would respond to climate warming. How much carbon might be released as temperatures increase? How will warming change the types of trees in forests of the future? Will changes in nitrogen cycling affect carbon storage in plants? In Brazil, scientists investigate how the clearing of tropical forests in the western Amazon changes greenhouse gases such as carbon dioxide and nitrous oxide released into the atmosphere. What will the effect be on global climate? How will change in temperature and atmospheric gas concentrations affect the productivity of forests? What effect does the clearing of forest for pasture have on tropical stream ecosystems? Scientists in the center use sophisticated computer models to ask questions about effects of future changes in climate, carbon dioxide and ozone on vegetation productivity and carbon storage world-wide. Center researchers collaborate with social and atmospheric scientists at MIT to investigate ecological responses to various scenarios of economic and energy development. E c o s y s t e m s C e n t e r Report 2008 1 Marginal Lands – An Emerging Issue in Global Ecology L arge portions of the Earth’s tropical regions are currently not used intensively by people. These lands are considered “marginal lands” for a variety of climatic, ecological, agronomic, infrastructural or sociopolitical reasons. They typically contain savanna, woodlands or seasonally dry forest where low water availability and low soil fertility have prevented development of intensive agriculture. In some cases, they are inaccessible by modern transportation or are sites of land conflicts or other sociopolitical barriers. Despite the low intensity of use, these lands serve important functions as producers of food and fuel, reservoirs of biodiversity, places to live and providers of ecosystem services for millions of people. 2 Ecosystems Center Rep o r t 2 0 0 8 Brown-MBL graduate student Shelby Hayhoe filters water for her research comparing pasture and forest watersheds in Tanguro Ranch, Mato Grasso, Brazil. (Chris Neill) Although considered for hundreds of years as “marginal land,” increases in human population and technological advances place these lands at the new frontier of intensification, poised to experience the most rapid land use change on Earth. These areas represent the promise of food security, energy security and economic development. They include most of the Earth’s potential new land for expansion of production of grains or biofuels for both local and global markets. Tropical marginal lands are the next frontline in the conflict between supplying increasing goods and services to a growing human population and maintaining natural ecosystems and the services they provide to societies. Photos below, left to right: A newly tilled area being converted from pasture to soybean field in Brazil. (Chris Neill) A field of soybeans, Brazil’s top export. (Chris Neill) Headwater watershed impounded by a small dam, typical of pasture landscapes in the Amazon. (Chris Neill) Intensification of the use of marginal lands will have a number of negative consequences. In many cases, the intensive use of marginal lands will require increased inputs of nutrients and water to make them reliably productive. The nutrient inputs could lead to water and air pollution, including the eutrophication of surface waters as excess nitrogen fertilizer runs off from agricultural fields and the acceleration of climate change as nitrogen in the fertilizer is transformed into nitrous oxide, a powerful greenhouse gas. Irrigation of marginal lands will put new demands on already stressed water supplies in many regions. In addition, the replacement of natural ecosystems with croplands or biofuels plantations could also have devastating effects on biodiversity and the capacity of natural terrestrial ecosystems to deliver many of the support services that humans rely on. The Ecosystems Center is in a unique position to provide science and education that can guide future management of marginal lands. Center scientists, in collaboration with colleagues at Brown and Columbia Universities and in Latin America and Africa, are developing a new interdisciplinary research and education program on marginal lands that draws collaborators in the areas of remote sensing, atmospheric science, watershed biogeochemistry, social science and economics and modeling, atmospheric exchanges, on the ground work in watershed biogeochemistry and modeling. This project will transform the intellectual scope of the research conducted at the Ecosystems Center by integrating social and natural science approaches to land cover change research, increasing student participation and by providing new insights and questions that arise from international experience, perspective and international exchanges. Humans rely on water for basic survival and economic development and today control more than half of all accessible water. E c o s y s t e m s C e n t e r Report 2008 3 Grounding Perceptions of Soil Sagebrush-dominated landscape on Bureau of Land Management grazing land near the Utah-Idaho border. (Zoe Cardon) Image through the microscope of soil microbes producing green fluorescent protein near roots of plants growing in the lab. (Patrick Herron) Soil. For millennia, humans have built with it, planted seeds in it, and depended on its resources for the most basic needs of life including shelter, water and food. Soil has also been maligned at times, described as “dirt” when tracked in from the garden, or, more recently, targeted by “germ”-killing soaps for those fearful of the millions of microbes teeming in its depths. But the microbes in soils are essential for ecosystem health; they are the natural recyclers of nutrients and natural decomposers that have kept ecosystems productive for millions of years. And, in our world today, soil microbes are particularly active around plant roots. Senior scientist Zoe Cardon of the Ecosystems Center studies the interface between living plant roots and soils, called “the rhizosphere.” The rhizosphere is a central commodities exchange in ecosystems, where organic compounds such as sugars and dead cells lost from roots fuel microbial decomposers that, in turn, can make nutrients available to plants for new growth. This provision of nutrients is a natural form of fertilization; in fact there are those who advocate “harnessing the rhizosphere” to maintain more naturally agricultural plant productivity while minimizing use of chemical fertilizers. 4 Ecosystems Center Rep o r t 2 0 0 8 Nutrient cycling isn’t the only major ecosystem function that is strongly influenced by plant-soil interactions. The rhizosphere interface between plant roots and soils is also a portal through which enormous amounts of water flow. Of the more than 60 trillion tons of water that move from soils to the atmosphere each year, nearly two-thirds passes from soil into roots, then through the bodies of plants, to be released by evaporation through miniscule valves from leaves into the air. Environmental engineers even exploit such plant control over soil water flow to redirect water streams underground or control the spread of pollutants. For all these reasons, the health of soils and the organisms living in them is of great concern worldwide, whether in areas where soil fertility is in decline, or areas where water is becoming scarce. Scarcity in Arid Lands—How Much Soil Water Can Plants Move? I nteractions among carbon, nutrient, and water cycles have been a continuing focus throughout the Ecosystems Center’s history, and new senior scientist Zoe Cardon continues this tradition with her research in semi-arid landscapes of the Western U.S. The productivity of these systems is strongly limited by the availability of water and nitrogen, and Cardon is especially interested in how dynamics of water availability affect the productivity of plants and activities of soil microbes. For the past four years, she has worked in the field with colleague John Stark of Utah State University on grazing lands in Northeastern Utah, just east of Bear Lake. At an elevation of nearly 7,000 feet, precipitation as snow during winter months is followed by periods of drought in late June and July, drought that is alleviated only once the monsoon season begins with significant August rains. Sagebrush shrubs are common in such Great Basin ecosystems, becoming more dominant with the increased grazing that has accompanied human settlement in the last 150 years. It was first demonstrated in 1987 that sagebrush can facilitate the redistribution water from wetter to drier soil underground. Unseen by our human eyes, water travels through the sagebrush roots, via miniscule, open pipes in the roots’ centers. This water movement tends to equalize the water content of soil around the entire sagebrush root system. Sagebrush can be deeply rooted, reaching down into the soil column a meter or more, so deep water can move at night up through roots and out into drier upper soil layers. Such dynamic redistribution of water at night is thought to enable enhanced plant activity during the next day. Water isn’t only moved upward, however. During late-summer rainstorms, rain that has soaked upper soil layers can move rapidly down through the sagebrush root systems to be released in drier soil deep in the soil column, thus moving it away from soil layers where it can readily evaporate to the atmosphere. This redistribution of water may be a major controller of hydrology at the landscape scale in Western ecosystems where sagebrush is dominant. Mathematical modeling in a slightly drier Rush Valley, Utah, landscape has previously suggested that as much as three-quarters of the rainwater may be redistributed rapidly to deep soil via sagebrush roots. Jed Rasmussen, REU intern from Utah State University, examines microbial activity by injecting tracer compounds into soil. (Zoe Cardon) Cardon’s current modeling suggests that in the Bear Lake area, the proportion of rainwater redistributed by sagebrush may not be that large, but it certainly is a major mechanism by which autumn rain makes its way downward to recharge water reserves in the soil column. Water isn’t the only limitation on plant productivity in such ecosystems, however. Nitrogen availability can also be sub-optimal, and Cardon and Stark are investigating how rates of nutrient cycling (and associated nutrient delivery to plants) catalyzed by soil microbes living among sagebrush roots is affected by rootmediated redistribution of water. In dry landscapes where ecosystem productivity and water conservation are contentious issues, it is particularly important to understand such major controls over fates of groundwater and precipitation. E c o s y s t e m s C e n t e r Report 2008 5 Taking a New Look at Old Growth A 500-year old growth Douglas fir forest in Oregon. (Mike Furniss, US Forest Service) Ecologists have assumed for decades that old-growth forests, also known as virgin or primeval forests, are carbon neutral. They were believed to take up as much carbon by photosynthesis and plant growth as they give back through plant, animal, and soil respiration. That is, until recent studies—including those by Ecosystems Center research scientist Jim Tang and his colleagues —found that old-growth forests serve as important sinks for carbon dioxide emitted by fossil-fuel burning. Old-growth forests are valuable as examples of ancient ecosystems and repositories of biodiversity. Now Tang’s research adds another dimension to their value: They should be included in carbon credit schemes designed to lower carbon dioxide emissions, such as cap-and-trade policies now under consideration by the United States and other nations. Old-growth forests were not included in national carbon budgets when negotiators set up the Kyoto Protocol, because they were believed to play no net role in carbon storage. No international treaties protect these ancient ecosystems. Tang’s research suggests we take a second look. 6 Ecosystems Center Rep o r t 2 0 0 8 Old-Growth Forests Continue Fixing Carbon I ncreased carbon dioxide concentration in the atmosphere is a primary cause of global climate change. Between 2000 and 2005, human beings emitted about 7 to 8 billion metric tons of carbon each year by burning fossil fuels, leading to an imbalance in the global carbon cycle. The land and ocean absorb about 4 to 5 billion tons of this anthropogenic (human-caused) carbon, but the atmosphere is gaining 3 billion tons per year, causing greenhouse warming. When scientists look more closely at terrestrial ecosystems, it appears that their carbon budget is nearly balanced. Plant respiration, soil respiration, and natural fire release about 117 billion tons of carbon each year, while plant photosynthesis absorbs about 120 billion tons. These natural carbon fluxes are huge compared to the fossil-fuels emissions. The net result is that terrestrial ecosystems absorb about 3 billion tons of carbon each year, acting as a sink for fossil fuel-derived carbon. Trees and grass fix carbon into biomass and soils. Carbon fluxes are measured from this 450-meter tower in Wisconsin. (Jim Tang) Old-growth forests are nondisturbed forests that have been growing for hundreds of years. In the United States, the majority of forests were harvested in the 19th and early 20th centuries, so old-growth forests are rare. Most forests in the United States are postharvest, second-growth forests or humanplanted forests still early in their life cycles. It was traditionally thought that oldgrowth forests are in a steady state, neither growing nor shrinking and respiring about as much carbon as they take up during photosynthesis. However, Ecosystems Center scientist Jim Tang and his colleagues at the University of Minnesota and Pennsylvania State University found that an old-growth forest in the upper peninsula of Michigan was a carbon sink, still growing and taking up excess carbon over its respiratory losses. Jim Tang measures soil respiration in a recently thinned forest. (Photo courtesy of Jim Tang) Tang’s group also revealed the underlying mechanism of carbon balance by studying a series of forests of increasing ages, from recently clearcut forests to young plantation, mature, and old-growth forests. The classical paradigm to explain the decrease in carbon uptake in aging forests is that photosynthetic uptake stabilizes while respiratory carbon loss increases. Tang and colleagues found that both photosynthesis and respiration decrease in aging forests, after peaking in middle age. Photosynthesis outpaces respiration in old-growth forests, resulting in a small net carbon sink, primarily stored in deep soils. This result could be explained by increased atmospheric carbon dioxide concentration and nitrogen deposition, both of which favor increased photosynthesis. These results have significant implications for forest management and carbon policy. Cutting mature and old-growth forests will reduce carbon storage in terrestrial ecosystems. The loss of carbon stored in soils and biomass after harvest cannot be offset by faster growth of young trees for several decades. To gain carbon credits, trees should be planted in non-forested areas, rather than cutting old trees and planting new ones. E c o s y s t e m s C e n t e r Report 2008 7 Soybean Agriculture Transforms Amazon Ecosystems The southern Brazilian Amazon is the largest agricultural frontier on Earth. Last year, soybeans from the Amazon pushed Brazil past the United States as the world’s top soybean supplier. Soybeans, sold mostly to Europe and China, are Brazil’s leading export. A soybean field in the southern Brazilian Amazon in the headwater region of the Xingu River. (Chris Neill) An international team of scientists, led by Ecosystems Center scientist Christopher Neill, examines how this radical land transformation influences the amount and quality of water that makes its way out of small watersheds and into the vast Amazon drainage network. Abundant rain is the lifeblood that makes soybean agriculture possible. Rainwater, cleansed by soils and vegetation in small watersheds, has fed the main Amazon tributaries for millennia. But deforestation reduces the amount of water that moves through trees and back to the atmosphere by evapotranspiration. This means more water can run off into streams, perhaps causing more erosion and carrying more sediment and soil nutrients with it. All of these processes are best studied at the scale of individual watersheds. Watershed studies have a long and important history in environmental studies. In the Amazon, they provide a critical, integrated picture of the consequences of human actions in one of the most rapidly changing places on Earth. We use them to identify important “tipping points,” where change passes critical thresholds that lead to even greater change. 8 Ecosystems Center Rep o r t 2 0 0 8 Scientists use seine net to catch fish in an Amazon pasture stream. (Chris Neill) Watershed Studies First to Compare Forest and Soybeans A fter a 20-minute walk through the humid air and dappled sunlight of an Amazon tropical forest, Brown-MBL student Shelby Hayhoe wades waist deep into a clear stream and ties a measuring tape to the opposite bank. Ecosystems Center Senior Research Assistant Richard McHorney secures the tape and hands her a current meter to measure the depth and velocity of the flowing water every 10 centimeters (4 inches) along the tape from bank to bank. The stream’s cross section dutifully recorded, McHorney unwraps a laptop computer from the safety of a plastic bag and plugs a cord into a data logging device tied securely to a stake at the stream’s edge. With a few keystrokes, he views the level of the stream water, recorded every hour on the hour for the last six months, and then transfers the data to his computer. Hayhoe will use the information to calculate exactly how much water flows downstream each year. Her study subject—a watershed— is a fundamental unit, long used by ecologists, to study the basic hydrological function of ecosystems. She and McHorney fill three bottles of water that they will use to measure sediment, nutrients and isotopes of oxygen, which provide information about how much streamwater arrived via groundwater or faster overland flows. Rich McHorney and Shelby Hayhoe collect data from a stream in Mato Grasso, Brazil. (Chris Neill) Later that day, they head to another stream. Only the setting is different. Instead of walking through forest, they drive 10 kilometers down a series of well-built roadways that crisscross across a landscape that has been transformed into neatly planted soybean fields that stretch nearly from horizon to horizon. Repeating the process, McHorney and Hayhoe measure stream depth and velocity and collect the automatically logged stream levels. This work, funded by a grant from the National Science Foundation to the MBL’s Ecosystems Center, brings together a team led by center scientist Christopher Neill that also includes Alex Krusche, a chemist from the University of São Paulo in Piracicaba, Helmut Elsenbeer, a hydrologist from Germany’s University of Potsdam, and Eric Davidson, a biogeochemist at the Woods Hole Research Center. The project is the first watershed-scale study of the impact of Amazon soybean agriculture. It is centered on Tanguro Ranch, a 200,000-acre farm owned by the agricultural consortium Grupo A, Maggi. Tanguro lies in the headwaters of the Xingu River, a major southern tributary of the Amazon. The large size of the study area is important—it allows us to compare whole watersheds in soybean fields with whole watersheds that remain forested. Already, Hayhoe’s results show that the total volume of water flowing in streams from soybean watersheds is nearly double that from forest watersheds. Her oxygen isotope measurements indicate that despite the higher flows in soybean streams, almost all of the streamwater arrives after a long passage through groundwater. These measurements are at the heart of questions vital to the future of the Amazonian forest and the people who make their living in the Amazon. First, as more and more land is cleared, more water will end up in larger rivers. This increases the risk of flooding—a phenomenon that may already be happening. Second, less water returned to the atmosphere means less water vapor available to form rain within the Amazon Basin itself. While we don’t yet know precisely the amount of clearing that will trigger larger-scale changes to rainfall, remote sensing combined with information from small watersheds will be essential for developing models that can predict these critical thresholds. E c o s y s t e m s C e n t e r Report 2008 9 Education SES students and instructors in the field and in the lab. (Tom Kleindinst) Semester in Environmental Science The Semester in Environmental Science (SES) at the MBL is currently the only academic year educational program available for undergraduates at a research institution in Woods Hole. Over the past 12 years, 180 students have completed the program and about half have gone on to receive graduate training in environmental science, policy or engineering. Nearly 70 percent of SES alumni remain involved in fields related to environmental science and management. In 2008, 14 students were admitted to the SES program from a variety of schools including Bates College, Connecticut College, Colorado College, Dillard University, Franklin and Marshall College, Lawrence University, Lafayette College, Mount Holyoke College, Northwestern University, SUNY-Environmental Science and Forestry School, and Wesleyan University. Although they were enrolled in U.S. colleges, this was an international group including students from Tanzania, China, Nepal, and Trinidad. To help assure a diverse student population and provide all students with equal access to the program, $84,059 in financial assistance was offered in 2008, a significantly larger amount than in prior years. This scholarship aid was derived from three major sources: a grant provided by the A.W. Mellon Foundation to support underrepresented groups in environmental science, gifts totaling $19,500 from individual donors, and endowment income from the Osterhout/Sears and Speck funds dedicated for undergraduate support. Wayne Daniel of Dillard University filters phytoplankton in the SES lab. (Ken Foreman) During the first 10 weeks of the program, students completed a set of structured lab and field exercises as part of the core courses and visited a variety of freshwater, estuarine and terrestrial sites. At each field site, they measured ecosystem structure (e.g., species composition and biomass of plants, animals and microbes present, light, salinity, soil characteristics, etc.) and function (e.g., photosynthesis, respiration, nutrient cycling and release). Students reported on their findings at weekly or bi-weekly discussion sessions and prepared written lab reports. Students also completed an elective course (in 2008, either mathematical modeling of ecosystems or microbial methods in ecology). During the last six weeks of the program, after the formal coursework ended, students pursued independent research projects and presented their findings at a public symposium held in December. Results from this work are submitted as final written project reports and are posted to our website, http://courses.mbl.edu/SES/. For more information about the SES program, please go to the website, http://courses.mbl.edu/SES/. 10 Ecosystems Center R e p o r t 2 0 0 8 One SES Student’s Story by Jennifer Peters A fter graduating from Bard College with a degree in ecological biology, I began searching for a “real job.” I’d had some broad experience working for the New York Department of Environmental Conservation on the Hudson River taking water quality measurements. But, like most recent college graduates, my resumé didn’t include a lot of professional science experience. I’d done a senior thesis on eastern coyotes, spent a January intersession in Kenya studying snakes, and during my junior year in SES, I completed a project on water and carbon budgets on Martha’s Vineyard. I managed to find some interesting temporary field assistant jobs working on a tree census in Puerto Rico and tagging sage grouse in Colorado, but I always hoped to return to the Ecosystems Center. When I was a student in SES, faculty member and Ecosystems Center senior scientist Gus Shaver gave a fascinating lecture on species composition shifts in the Arctic tundra in response to climate change. I remember Gus’s enthusiasm as he told us the complex tale of feedbacks that might occur if global warming stimulated nutrient release from frozen tundra soils. Ever since that lecture, I’d hoped to have a chance to do research first-hand on the North Slope of Alaska. Then I saw a posting for a summer research assistantship working with Gus. I got the job and spent last summer working at Toolik Lake field station! Even more exciting, I was hired as a full time employee at the Ecosystems Center to continue work on the Toolik Lake research site, and to be the teaching assistant in the Fall SES Program in 2008. So, two and a half years after finishing at SES, I found myself ankle-deep in soggy tussock tundra, fertilizing the plots Gus had talked about and building the greenhouses I had seen in pictures. The field station is about 140 miles north of the Arctic Circle. You can walk for miles across the rolling hills of tundra, with wet feet, tripping over tussocks, and still see camp. Not a particularly elegant sight, camp was a conglomeration of Army fatigue green trailers and tents sitting next to a gravel access road running parallel to the trans-Alaska oil pipeline. My job was to help out on many of the different research projects that worked out of the terrestrial lab. For this I relied very heavily on my SES lab experience. I utilized many of the techniques we covered during the core SES courses. I used an infrared gas analyzer to measure ecosystem photosynthesis, measured leaf area, and used buried bags to estimate nitrogen mineralization in the soil. I even used the wet chemistry we learned in SES to measure phosphate and nitrate in soil extracts, and determined carbon and nitrogen content of leaf samples using an elemental analyzer. My main responsibility during the summer was measuring light reflectance from the tundra, essentially the greenness, of vegetation across a fertilization gradient. We will use this data to scale up measurements of biomass based on remote sensing data and learn something about areas that are even more inaccessible than Toolik, such as the 1000 km2 area burned during the Anakturak River fire. During 2007, unusually dry and warm conditions and an increased incidence of lightning strikes that may be occurring due to climate change triggered a major fire on the tundra. The fire blackened the surface and exposed the frozen soil, leading to further thawing during the summer of 2008. This was the first major fire recorded in the North Slope over the last 10,000 years and it is estimated that it released more than 2 million metric tons of CO2 into the atmosphere, burning off the top 12 cm of moss. One of the most exciting datasets I collected while at Toolik was the change in reflectance and thaw depth recorded from the burned areas over the summer as the landscape began to re-vegetate. Gus’s lecture during SES convinced me that Arctic ecosystems are some of the most fascinating places on Earth to study—first, because their function is not as well understood as ecosystems in temperate or tropical climates, and second, because they are experiencing extreme warming. It turns out that about 1,000 billion metric tons of carbon, an amount greater than the pool of CO2 in the atmosphere, is thought to be tied up in permafrost soils. The question of what will happen to this carbon as the Arctic warms is really important! E c o s y s t e m s C e n t e r Report 2008 11 Education and Outreach Science journalists collect invertebrates from a stream at the Long Term Ecological Research (LTER) site, Toolik Lake, Alaska. (Chris Neill) T he Ecosystems Center is actively involved in education in a variety of ways. In addition to running the Semester in Environmental Science program for college undergraduates, center scientists are professors and advisors in the Brown-MBL Graduate Program, members of doctoral committees and mentors for postdoctoral scientists and undergraduate interns. The center staff also takes part in a range of community outreach activities to increase public understanding of science. Schoolyard Long-Term Ecological Research Projects The Arctic Schoolyard LTER is based at Barrow, Alaska, and designed for students, mostly Native American Inupiat, their teachers and local residents. It consists of “Schoolyard Saturday,” a weekly series of lectures and field demonstrations by visiting scientists, and two field activities for Barrow students and teachers. One field experiment measures the effects of climate warming on tundra vegetation; the second experiment measures changes in lake water chemistry. The Plum Island Ecosystem (PIE) Schoolyard LTER conducts a project with the Massachusetts Audubon Society’s Salt Marsh Science Program, a program providing environmental education to more than 700 middle and high school students in the coastal region of northeastern Massachusetts. These activities engage them in salt marsh research near their homes and include monitoring the growth of Phragmites in salt marshes, studying the effect of salinity on the growth of salt marsh vegetation and determining the impact of tidal restrictions on fish. Through an additional educational effort, led by Governer’s Academy in Rowley, school students study the distribution of plants and animals at PIE field sites and maintain a longterm database. Barrow, Alaska, students at an experimental station on the tundra, part of the Arctic Schoolyard LTER. (Deborah Greene) The Palmer Station Schoolyard LTER collaborates with a number of educational organizations to create interdisciplinary projects that are based on research by Palmer scientists, and maintains a blog site reporting the progress of its annual oceanographic cruise. Undergraduate Internships With funding from the National Science Foundation (NSF) and other groups, the Ecosystems Center has offered many college students the opportunity to undertake research projects in the lab and at field sites. In 2008, nine undergraduates from the University of Massachusetts - Lowell, Clark University, the University of Michigan, Western Washington University, the University of North Carolina, the University of California, San Diego and the College of William and Mary conducted research projects through NSF’s Research Experience for Undergraduate (REU) program. Their projects ranged from studying the effects of fire on the organic and inorganic chemistry of tussock tundra soil water in Alaska, to research on the effects of herbivory in a nitrogen-enriched salt marsh at the Plum Island LTER in northeastern Massachusetts, to bacterial ecology research at the Palmer LTER site in Antarctica. 12 Ecosystems Center R e p o r t 2 0 0 8 Brown-MBL Graduate Program A children’s book, Sea Secrets: Tiny Clues to a Big Mystery, was inspired in part by research at the Palmer Station LTER in Antarctica. (Beth Simmons) Five students are working under the supervision of Ecosystems Center scientists in the MBL’s graduate program with Brown University. Gillian Galford is studying regional and global consequences of the expansion of mechanized agriculture in the Brazilian Amazon with Jerry Melillo of the Ecosystems Center and Jack Mustard of Brown. Shelby Hayhoe is looking at the effect of land use change on biogeochemical cycling in tropical systems, focusing on agricultural conversion in the Amazon. Her advisors are Christopher Neill of the Ecosystems Center and Stephen Porder from Brown. Kristen Myers is conducting her research on bacterial community structure in coastal Antarctica with Hugh Ducklow of the Ecosystems Center and Jeremy Rich of Brown. Yawei Luo’s research with Ducklow and Warren Prell of Brown uses numerical simulation models to study plankton dynamics and nutrient cycling with emphasis on the open ocean. Lindsay Brin is examining how temperature influences nitrogen pathways in estuaries and mangroves. Her advisors are Anne Giblin from the Ecosystems Center and Jeremy Rich from Brown University. Cambridge, Massachusetts, Youth Programs and is sponsored by the National Science Foundation. According to its director, Ari Epstein of the MIT, the program was designed to “interest, inspire and excite” the teenage generation with interesting stories produced by their peers on science, technology, engineering and mathematics. Logan Science Journalism Program Environmental Fellows from MIT visited the Ecosystems Center for their annual retreat to hear presentations by the center’s Plum Island, Arctic, and Antarctic LTER researchers, and to network among graduate students and scientists pursuing environmental, energy and sustainability research topics. In 2008, 10 journalists, led by Christopher Neill, participated in the MBL’s Logan Science Journalism Program’s Polar Science Fellowship, created for the International Polar Year. They traveled to the LTER site at Toolik Lake, Alaska. A number of interviews, articles and blogs resulted from their two-week stay at Toolik. Three polar fellows and Neill will also spend a month next Austral summer at Palmer Station on the Antarctic Peninsula. Members of the Ecosystems Center staff continue to judge community and state science fairs for students in kindergarten through grade 12 and mentor junior high school students. The center also continued its participation in the Woods Hole Science and Technology Education Partnership (WHSTEP), providing assistance to teachers and students in the local school systems. Senior research assistant Matthew Erickson gave an overview of Palmer LTER to teachers from Upper Cape Cod schools at WHSTEP’s annual dinner and meeting in 2008. Science Outreach Matthew Erickson describes research at the Palmer Station LTER site in Antarctica to science teachers from Cape Cod schools. (Debbie Scanlon) Rachel Franzblau, REU intern from the University of Michigan, analyzes organic compounds from sediment traps in Maureen Conte’s Oceanic Flux Program. (J.C. Weber) In August, a group of urban high school students from Terrascope Youth Radio produced “Science Minutes,” interviewing Ecosystems Center senior scientists Anne Giblin and Zoe Cardon and other Woods Hole scientists. Terrascope Youth Radio is a partnership project of the Massachusetts Institute of Technology (MIT) and the City of Ecosystems Center staff members serve on many town committees, including the Falmouth Zoning Board and Falmouth Conservation Commission, Falmouth Associations Concerned with Estuaries and Salt Ponds, the Association to Preserve Cape Cod, the Falmouth Coastal Resources working group, the Nutrient Management working group and the Falmouth Ashumet Plume Nitrogen-Offset Committee and the Falmouth Solid Waste Advisory committee. E c o s y s t e m s C e n t e r Report 2008 13 News Jerry Melillo and Brown-MBL graduate student Gillian Galford attended a fourday workshop in Segou, Mali, in July. Thirty scientists took part in the U.S.-Africa Workshop: Building research collaborations on nitrogen cycling in African AgroEcosystems, associated with the Millenium Villages Project. Gillian Galford (Leigh Winowiecki) An update on global warming, Global Climate Change: Its Impacts in the United States was co-edited by Jerry Melillo with Thomas Karl and Thomas Peterson from NOAA’s National Climatic Data Center in Asheville, North Carolina. The report, to be released in spring of 2009, was commissioned by the U. S. Government’s Climate Change Science Program to summarize what is known about the science of climate change and its impacts on the United States. John Hobbie was named a fellow of the American Academy of Arts and Sciences, one of the nation’s most prestigious honorary societies. Hobbie, a senior scholar at the Ecosystems Center and lead principal investigator of the Arctic Long Term Ecological Research (LTER) project, also received the Redfield Award from the American Society of Limnology and Oceanography (ASLO). Bruce Peterson was the recipient of ASLO’s Martin Award. Joe Vallino was in Antarctica at McMurdo Station in January as a member of the LTER Site Review team for the McMurdo Dry Valley LTER project. Ivan Valiela is a member of the Ecosystems Sciences and Management working group of the NOAA’s Science Advisory Board, and is editor of Estuarine, Coastal and Shelf Science. Zoe Cardon has been elected the new president of the Physiological Ecology Section of Ecological Society of America (ESA). She is the first female president of that research group. Jim Tang chaired the session, “Ecosystem Function: NPP,” for the ESA annual meeting in Milwaukee in August. MBL Visiting Scientist James Galloway, (University of Virginia) was the recipient of the 2008 Tyler Prize for Environmental Achievement, the premier award for environmental science, energy, and In the fall, Gus Shaver began a sabbatical environmental health, and considered in Fairbanks, Alaska, building collaborations the equivalvent of a Nobel Prize in those with other scientists from Toolik Field fields. Galloway works each summer Station of the Arctic LTER and with the with Ecosystems Center scientists and in Bonanza Creek LTER in Fairbanks. On an 2008 also spent his sabbatical here from international level, he serves on the steering September to December. committee of the International Study of Arctic Change (ISAC). 14 Ecosystems Center R e p o r t 2 0 0 8 Dan Arvizu, Director of the National Research Ecology Laboratory and NSF Science Board member, and Gus Shaver at the Long Term Ecological Research site at Toolik Lake, Alaska. Members of the Science Board visited the Toolik site in August. (John Hobbie) Maureen Conte led a French/US expedition in October to a remote lake in French Guiana to collect sediment cores for a reconstruction of Holocene climate variability in the northeastern Amazon. Linda Deegan was a featured lecturer at the 20th anniversary of the founding of the Waquoit Bay National Estuarine Research Reserve. Ed Rastetter spent a month in Edinburgh, Scotland, working with Mathew Williams on data assimilation techniques for carbon flux data derived from eddy covariance towers. Paul Colinvaux wrote a book on his 40 years of research in the Amazon, Amazon Exhibitions: My Quest for the Ice-Age Equator, published by Yale University Press. Chris Neill was elected president of FACES (Falmouth Associations Concerned with Estuaries and Salt Ponds). Ed Rastetter in an old growth Caledonian Forest in the Southern Highlands, near Pitlochry, Scotland. (Philip Wookey) Anne Giblin was appointed to the board of directors of the Gulf of Maine Institute, a nonprofit organization whose mission is to inspire young people, in partnership with adults, to become stewards of the Gulf of Maine and its watershed. Giblin also assumed leadership of the Plum Island LTER project in 2008. As part of the International Polar Year, Hugh Ducklow spent July, August and September at the Palmer field station in Antarctica in the Austral winter studying bacterioplankton community structure. At the Ecosystems Center, he was host to Xosé (Xelu) Morán of the Instituto Español de Oceanografía, Xixon, Spain. Morán conducted research on bacterioplankton population dynamics in Waquoit Bay. Toolik Field Station on the North Slope of Alaska. (John Hobbie) E c o s y s t e m s C e n t e r Report 2008 15 LTER site at Palmer Station in Antarctica, as seen from Torgeson Island. (Hugh Ducklow) Publications 2008 Bowden, WB; Gooseff, MN; Balser, A; Green, A; Peterson, BJ; Bradford, J. 2008. Sediment and nutrient delivery from thermokarst features in the foothills of the North Slope, Alaska: Potential impacts on headwater stream ecosystems. Journal of Geophysical Research 113 G02026, DOI:10.1029/2007JG000470. Bradford, MA; Davies, CA; Frey, SD; Maddox, TR; Melillo, JM; Mohan, JE; Reynolds, JF; Treseder, KK; Wallenstein, MD. 2008. Thermal adaptation of soil microbial respiration to elevated temperature. Ecology Letters 11(12):1316-1327. Bowen, JL; Valiela, I. 2008. Using delta15N to assess coupling between watersheds and estuaries in temperate and tropical regions. Journal of Coastal Research 24(3):804-813. Bret-Harte, MS; Mack, MC; Goldsmith, GR; Sloan, DB; DeMarco, J; Shaver, G; Ray, PM; Biesinger, Z; Chapin FS III. 2008. Plant functional types do not predict biomass responses to removal and fertilization in Alaskan tussock tundra. Journal of Ecology DOI:10.1111/j. 1365-2745.2008.01378. Buchsbaum, RN; Deegan, LA; Horowitz, J; Garritt, RH; Giblin, AE; Ludlam, JP; Shull, D. 2008. Effects of regular salt marsh haying on marsh plants, algae, invertebrates and birds at Plum Island Sound, Massachusetts. Wetland Ecology and Management DOI:10.1007/s11273008-9125-3. Burton, AJ; Melillo, JM; Frey, SD. 2008. Adjustment of forest ecosystem root respiration as temperature warms. Journal of Integrative Plant Biology 50(11):1467-1483. Cardon, ZG; Gray, DW; Lewis, LA. 2008. The green algal underground – evolutionary secrets of desert cells. BioScience 58(2):114-122. Colinvaux, P. 2008. Amazon Expeditions: My Quest for the Ice-Age Equator. Yale University Press, New Haven and London. 328 pp. Ducklow, H. 2008. Microbial services: Challenges for microbial ecologists in a changing world. Aquatic Microbial Ecology 53:13-19. Cooper, L.W; McClelland, JW; Holmes, RM; Raymond, PA; Gibson, JJ; Guay,CK; Peterson, BJ. 2008. Flow-weighted values of runoff tracers (18O, DOC, Ba, alkalinity) from the six largest Arctic rivers. Geophysical Research Letters 35 L18606, DOI:10.1029/2008GL035007. Ducklow, HW; Erickson, M; Kelly, J; Montes-Hugo, M; Ribic, CA; Smith, RC; Stammerjohn, SE; Karl, DM. 2008. Particle export from the upper ocean over the continental shelf of the west Antarctic Peninsula: A long-term record, 1992-2007. DeepSea Research II 55:2118-2131. Corell, RW; Hassol SJ; Melillo, JM. 2008. Emerging challenges: Methane from the Arctic: Global warming wildcard. Pp. 37-48 in: P Harrison, ed. UNEP Yearbook 2008. An Overview of Our Changing Environment. Division of Early Warning and Assessment (DEWA), United Nations Environment Programme (UNEP), Nairobi, Kenya. Ducklow, HW. 2008. Long-term studies of the marine ecosystem along the west Antarctic Peninsula. Deep-Sea Research II 55:1945-1948. Culbertson, JB; Valiela, I; Olsen, YS; Reddy, CM. 2008. Effect of field exposure to 38-year-old residual petroleum hydrocarbons on growth, condition index, and filtration rate of the ribbed mussel, Geukensia demissa. Environmental Pollution 154:312-319. Culbertson, JB; Valiela, I; Pickart, M; Peacock, EE; Reddy, CM. 2008. Long-term consequences of residual petroleum on salt marsh grass. Journal of Applied Ecology DOI:10.1111 /j.1365-2664.2008.01477. Davidson, EA; Asner, GP; Stone, TA; Neill, C; Figueiredo, RO. 2008. Objective indicators of pasture degradation from spectral mixture analysis of Landsat imagery. Journal of Geophysical Research G: Biogeosciences 113: Art. No. G00B03 10.1029/2007JG000622. Carmichael, RH; Hattenrath, T; Valiela, I; Michener, RH. 2008. Nitrogen stable isotopes in the shell of Mercenaria mercenaria trace wastewater inputs from watershed to estuarine ecosystems. Aquatic Biology 4:99-111. Desai, AR; Noormets, AN; Bolstad, PV; Chen, J; Cook, BD; Curtis, PV; Davis, KJ; Euskirchen, ES; Gough, C; Martin, JM; Ricciuto, DM; Schmid, HP; Su, H; Tang, J; Vogel, C; Wang, W. 2008. Influence of vegetation type, stand age and climate on carbon dioxide fluxes across the Upper Midwest, USA: Implications for regional scaling of carbon flux. Agricultural and Forest Meteorology 148:288-308. Chaves, J; Neill, C; Elsenbeer, H; Krusche, A; Germer, S; Gouveia Neto, S. 2008. Land management impacts on runoff sources in small Amazon watersheds. Hydrological Processes 22:1766-1775. Drake, DC; Peterson, BJ; Deegan, LA; Harris, LA; Miller, EE; Warren, RS. 2008. Plant nitrogen dynamics in fertilized and natural New England saltmarshes: A paired 15N tracer study. Marine Ecology Progress Series 354:35-46. 16 Ecosystems Center R e p o r t 2 0 0 8 Ducklow, HW; Doney, SC; Steinberg, DK. 2008. Contributions of long-term research and timeseries observations to marine ecology and biogeochemistry. Annual Review of Marine Science 1:279-302. Ewers, BE; Mackay, DS; Tang, J; Bolstad, P; Samanta, S. 2008. Intercomparison of sugar maple stand transpiration responses to environmental conditions from the western Great Lakes Region of the United States. Agricultural and Forest Meteorology 148:231-246. Fleeger, JW; Johnson, DS; Galvan, KA; Deegan, LA. 2008. Top-down and bottom-up control of infauna varies across the salt marsh landscape. Journal of Experimental Marine Biology and Ecology 357:20-34. Fox, SE; Stieve, E; Valiela, I; Hauxwell, J; McClelland, J. 2008. Macrophyte abundance in Waquoit Bay: Effects of land-derived nitrogen loads on seasonal and multi-year biomass patterns. Estuaries and Coasts 31(3):532-541, 10.1007/s12237-008-9039-6. Frey, SD; Drijber, R; Smith, H; Melillo, J. 2008. Microbial biomass, functional capacity, and community structure after 12 years of soil warming. Soil Biology and Biochemistry 40(11):2904-2907, DOI:10.1016/j. soilbio.2008.07.020. Frumhoff, PC; McCarthy, JJ; Melillo, JM; Moser, SC; Wuebbles, DJ; Wake, C; Spanger-Siegfried, E. 2008. An integrated climate change assessment for the Northeast United States. Mitigation and Adaptation Strategies for Global Change 13: 419-423. Caption Fry, B; Cieri, M; Hughes, J; Tobias, C; Deegan, L; Peterson, B. 2008. Stable isotope monitoring of benthic-planktonic coupling using salt marsh fish. Marine Ecology Progress Series 369:193-204. Gage, DJ; Herron, PH; Pinedo, CA; Cardon, ZG. 2008. Live reports from the soil grain – the promise and challenge of microbiosensors. Functional Ecology 22:983-989. Galford, GL; Mustard, JF; Melillo, JM; Gendrin, A; Cerri CC; Cerri, CEP. 2008. Wavelet analysis of MODIS time series to detect expansion and intensification of row-crop agriculture in Brazil. Remote Sensing of Environment 112(2):576-587. Gasol, JM; Pinhassi, J; Alonso-Sáez, L; Ducklow, H; Herndl, GJ; Koblížek, M; Labrenz, M; Luo, Y; Morán, XAG; Reinthaler, T; Simon, M. 2008. Towards a better understanding of microbial carbon flux in the sea. Aquatic Microbial Ecology 53:21-38. Geisz, HN; Dickhut, RM; Cochran, MA; Fraser WR; Ducklow, HW. 2008. Melting glaciers: A probable source of DDT to the Antarctic marine ecosystem. Environmental Science and Technology 10.1021/ es702919n. Haas, HL; Freeman, CJ; Logan, JM; Deegan, LA; Gaines, EF. 2008. Examining mummichog growth and movement: Are some individuals making intra-season migrations to optimize growth? Journal of Experimental Marine Biology and Ecology DOI:10.1016/j.jembe.2008.09.027. Hobbie, EA; Hobbie, JE. 2008. Natural abundance of 15N in nitrogen-limited forests and trundra can estimate nitrogen cycling through mycorrhizal fungi: A review. Ecosystems 11:815-830. Hobbie, JE; Laybourn-Parry, J. 2008. Heterotrophic microbial processes in polar lakes. Pp. 197-212 in Polar Lakes and Rivers: Limnology of Arctic and Antarctic Aquatic Ecosystems. WF Vincent, J Laybourn-Parry, eds. Oxford University Press, Oxford. Holmes, RM; McClelland, JW; Raymond, PA; Frazer, BB; Peterson, BJ; Stieglitz, M. 2008. Lability of DOC transported by Alaskan rivers to the Arctic Ocean. Geophysical Research Letters 35(3): Art. No. L03402, 10.1029/2007GL032837. Hopkinson, CS; Giblin, AE. 2008. Salt marsh nitrogen cycling. Pp. 977-1022 in Nitrogen in the Marine Environment. R Capone, D Bronk, M Mulholland, E Carpenter, eds. Elsevier Publishers. Huang, S; Conte, M. 2008. Source/process apportionment of major and trace elements in sinking particles in the Sargasso Sea. Geochimica et Cosmochimica Acta 10.1016/j.gca.2008.08.023 Knapp, AK; Briggs; JM; Collins, SL; Archer, SR; Bret-Harte, MS; Ewers, BE; Peters, DP; Young, DR; Shaver, GR; Pendall, E; Cleary, MB. 2008. Shrub encroachment in North American grasslands: Shift in growth form dominance rapidly alters control of ecosystem C inputs. Global Change Biology 14(3):615-623. Lambers, H; Raven, JA; Shaver, G; Smith, SE. 2008. Specialised nutrient-acquisition strategies reflect plant adaptations to changing N and P status as soils change over geological time scales. Trends in Ecology and Evolution 23(2):95-103. McClintock, J; Ducklow, H; Fraser, W. 2008. Ecological responses to climate change on the Antarctic Peninsula. American Scientist 96: 302-310. McKnight, DM; Gooseff, MN; Vincent, WF; Peterson, BJ. 2008. High-latitude rivers and streams. Pp 83-102 in Polar Lakes and Rivers: Limnology of Arctic and Antarctic Aquatic Ecosystems. WF Vincent, J Laybourn-Parry, eds. Oxford University Press, Oxford. McNamara, J; Kane, D; Hobbie, J; Kling, G. 2008. Hydrologic and biogeochemical controls on the spatial and temporal patterns of nitrogen and phosphorus in the Kuparuk River, arctic Alaska. Hydrological Processes DOI:10.1002/hyp.6920. Melillo, J; Sala, O. 2008. Ecosystem services. Pp. 75-115 in E Chivian, A Bernstein, eds. Sustaining Life: How Human Health Depends on Biodiversity. Oxford University Press, New York, NY. Morán, XAG; Calvo-Díaz, A. 2008. Single-cell vs. bulk activity properties of coastal bacterioplankton over an annual cycle in a temperate ecosystem. FEMS Microbial Ecology 1–14. Mulholland, PJ; Helton, AM; Poole, GC; Hall, RO Jr.; Hamilton, SK; Peterson, BJ; Tank, JL; Ashkenas, LR; Cooper, LW; Dahm, CN; Dodds, WK; Findlay, SEG; Gregory, SV; Grimm, NB; Johnson, SL; McDowell, WH; Meyer, JL; Valett, HM; Webster, JR; Arango, CP; Beaulieu, JJ; Bernot, MJ; Burgin, AJ; Crenshaw, CL; Johnson, LT; Niederlehner, BR; O’Brien, JM; Potter, JD; Sheibley, RW; Sobota, DJ; Thomas, SM. 2008. Stream denitrification across biomes and its response to anthropogenic nitrate loading. Nature 452:202-205. Nowinski, N; Trumbore, SE; Schuur, E; Mack, M; Shaver, G. 2008. Nutrient addition prompts rapid destabilization of organic matter in an Arctic tundra ecosystem. Ecosystems 11:16-25. Robertson, GP; Dale, VH; Doering, OC; Hamburg, SP; Melillo, JM; Wander, MM; Parton, WJ; Adler, PR; Barney, JN; Cruse, RM; Duke, CS; Fearnside, PM; Follett, RF; Gibbs, HK; Goldemberg, J; Mladenoff, DJ; Ojima, D; Palmer, MW; Sharpley, A; Wallace, L; Weathers, KC; Wiens, JA; Wilhelm, WW. 2008. Sustainable biofuels redux. Science 322(5898):49-50, 10.1126/science.1161525. San Gil, I; Sheldon, W; Schmidt, T; Servilla, M; Aguilar, R; Gries, C; Gray, T; Field, D; Cole, J; Pan, J; Palanisamy, G; Henshaw, D; O’Brien, M; Kinkel, L; McMahon, K; Kottmann, R; AmaralZettler, L; Hobbie, J; Goldstein, P; Guralnick, RP; Brunt, J; Michener, WK. 2008. Defining linkages between the GSC and NSF’s LTER Program: How the ecological metadata language (EML) relates to GCDML and other outcomes. OMICS: A Journal of Integrative Biology 12(2):151-156, DOI:10.1089/ omi.2008.0015. Sokolov, AP; Kicklighter, DW; Melillo, JM; Felzer, B; Schlosser, CA; Cronin, TW. 2008. Consequences of considering carbon/ nitrogen interactions on the feedbacks between climate and the terrestrial carbon cycle. Journal of Climate 21:3776-2796, DOI:10.1175/2008JCLI2038.1. Tang, J; Bolstad, PV; Desai,AR; Martin, JG; Cook, BD; Davis, KJ; Carey, EV. 2008. Ecosystem respiration and its components in an old-growth forest in the Great Lakes region of the United States. Agricultural and Forest Meteorology 148:171-185. Teichberg, M; Fox, SE; Aguila, C; Olsen, YS; Valiela, I. 2008. Macroalgal responses to experimental nutrient enrichment in shallow coastal waters: growth, internal nutrient pools, and isotopic signatures. Marine Ecology Progress Series 368:117-126. Tian, H; Liu, J; Melillo, JM; Liu, M; Kicklighter, D; Yan X; Pan, S. 2008. The Terrestrial Carbon Budget in East Asia: Human and Natural Impacts. Pp. 163-175 in C Fu, J Freney, J Steward, eds. Changes in the Human-Monsoon System of East Asia in the Context of Global Change. World Scientific Publishing Co. Pte. Ltd., Singapore, Hackensack, London. Valiela, I; Fox, SE. 2008. Managing coastal wetlands. Science 319:290-291. Valiela, I.; Fox, S. 2008. Mechanisms of ecological control over time: Evidence from coastal ecosystem. Pp. 223-243 in F Valladares, A Camacho, A Elosegui, M Estrada, C Gracia, JC Senar, JM Gili, eds. Unity in Diversity. Ed Rubes, Fundación BBVA, Madrid. Vincent, WF; Hobbie, JE; Laybourn-Parry, J. 2008. Introduction to high latitude limnology. Pp. 1-23 in WF Vincent, J Laybourn-Parry, eds. Polar Lakes and Rivers: Limnology of Arctic and Antarctic Aquatic Ecosystems. Oxford University Press, Oxford. Wan, Z, Vallino, JJ; Peterson, BJ. 2008. Study of the inter-annual food web dynamics in the Kuparuk River with a first order approximation inverse model. Ecological Modelling 211:97-112. Wollheim, W.M., Peterson, BJ; Thomas, SM; Hopkinson, CH; Vörösmarty, CJ. 2008. Dynamics of N removal over annual time periods in a suburban river network. Journal of Geophysical Research 113:G03038, DOI:10.1029/2007JG000660. Wollheim, WM; Vorosmarty, CJ; Bouwman, AF; Green, P; Harrison, J; Linder, E; Peterson, BJ; Seitzinger, SP; Syvitski, JPM. 2008. Global N removal by freshwater aquatic systems using a spatially distributed, within-basin approach. Global Biogeochemical Cycles 22 (2): Art. No. GB2026, 10.1029/2007GB002963. Zimmermann, A; Germer, S; Neill. C; Krusche, AV; Chaves J; Elsenbeer, H. 2008. Spatio– temporal patterns of throughfall water and solute deposition in an open tropical rain forest, south–western Amazonia, Brazil. Journal of Hydrology 360:87-102, DOI:10.1016/j. hydrol.2008.07.028. E c o s y s t e m s C e n t e r Report 2008 17 In Press Baeta, A; Pinto, R; Valiela, I; Richard, P; Niquil, N; Marques, JC. δ15N and δ13C in the Mondego estuary food web: Seasonal variation in producers and consumers. Marine Environmental Research. Baeta, A; Valiela, I; Rossi, F; Pinto, R; Richard, P; Niquil, N; Marques, JC. Eutrophication and trophic structure in response to the presence of the eelgrass Zostera noltii. Marine Biology. Kate Morkeski samples Fish Brook in Boxford, Massachusetts, as part of a nitrogen cycling study. (Martin Briggs) 18 Ecosystems Center R e p o r t 2 0 0 8 and climate on the water budget of the Ipswich River Basin, Massachusetts, USA. Water Resources Research. Giblin, AE. Iron and Manganese, in G. Likens, ed. The Encyclopedia of Inland Waters. Elsevier Press. Cole, ML; Kroeger, KD; McClelland, JW; Valiela, I. Effects of watershed land use on nitrogen concentrations and δ15N of nitrogen in groundwater. Biogeochemistry. Harrison, J; Maranger, R; Alexander, R; Giblin, AE; Jacinthe, P; Mayorga, E; Seitzinger, S; Sobota, D; Wollheim, W. The regional and global significance of nitrogen removal in lakes and reservoirs. Biogeochemistry. Deegan, LA; Neill, C; Victoria, RL; Krusche, AV; Ballester, MVR; Thomas, SM; Haupert, CL. Using Ballester, MVR; Victoria, whole stream 15N RL; Krusche, AV; additions to streams to Bernardes, M; Neill, C; understand the effects Deegan, L; Richey, JE. of land use change Physical and human on stream function. controls on the carbon Application of isotope composition of organic techniques for water matter in tropical quality assessment rivers: an integrated and management, analysis of landscape focusing on nutrient properties and river management in rivers. isotopic composition. International Atomic Application of isotope Energy Agency, Vienna, techniques for water Austria. quality assessment and management, Fennel, K; Brady, D; focusing on nutrient DiToro, D; Fulweiler, management in rivers. RW; Gardner, WS; International Atomic Giblin, A; McCarthy, Energy Agency, Vienna, MJ; Rao, A.; Seitzinger, Austria. S; Thouvenot-Korppoo, M; Tobias, C. Modeling Bowen, JL; Crump, BC; denitrification in Deegan, LA; Hobbie, aquatic sediments. JE. Increased supply Biogeochemistry. of ambient nitrogen has minimal effect on Fry, B; Cieri, M; salt marsh bacterial Hughes, J; Tobias, C; production. Limnology Deegan, LA; Peterson, and Oceanography. B. Stable Isotope monitoring of benthicCerri, CEP; Bernoux, M; pelagic coupling with Chaplot, V; Volkoff, B; salt marsh fish. Marine Vicotira, RL; Melillo, JM; Ecology Progress Paustian, K; Cerri, CC. Series. Nova Vida agronomic experiment: 1> Taking Germer, S; Neill, C; into account the Vetter, T; Chaves, J; spatial variability of soil Krusche, AV; Elsenbeer, properties for selecting H. Implications of longthe experimental area. term land-use change Plant and Soil. on the hydrology and solute budgets Claessens, L; Rastetter, of small catchments E; Hopkinson, C; in Rondônia (Brazil). Vallino, J; Canfield, S; Journal of Hydrology. Pontius, R. Evaluating the effect of historical changes in land use Hobbie, JE; Hobbie, EA; Weber, JC; Shamhar, J; Drossman, H; Conte, M. Mycorrhizal fungi supply nitrogen to host plants in arctic tundra and boreal forests: 15 N is the key signal. Canadian Journal of Microbiology. Johnson, DS; Fleeger, JW; Deegan, LA. Largescale manipulations reveal top-down and bottom-up controls interact to alter habitat utilization by saltmarsh fauna. Marine Ecology Progress Series. Kniffin, M; Neill, C; McHorney, RM; Gregory, G. Nutrient limitation of periphyton and phytoplankton in Cape Cod coastal plain ponds. Northeastern Naturalist. Koop-Jakobsen, K; Giblin, AE. Anammox in tidal marsh sediments: The role of salinity, nitrogen loading and marsh vegetation. Estuaries and Coasts. Neill, C; Bezerra, MO; McHorney, R; O’Dea, CB. Distribution, species composition and management implications of seed banks in southern New England coastal plain ponds. Biological Conservation. Tian, H; Liu, J; Melillo, JM; Liu, M; Kicklighter, D; Yan, X; Pan, S. The terrestrial carbon budget in East Asia: Human and natural impacts, in C. Fu; J. Freney; J. Steward, eds. Changes in the Human-Monsoon System of East Asia in the Context of Global Change. SCOPE Series, Island Press, Washington, DC. Valiela, I; Kinney, E; Culbertson, J; Peacock, E; Smith, S. Global losses of mangroves and salt marshes: Magnitudes, causes and consequences, in C. Duarte, ed. Global Loss of Coastal Habitats: Magnitudes, Causes, and Consequences. Fundacion BBVA. Madrid. Van Wijk, MT; Street, LE; Williams, M; Shaver, GR. Evapotranspiration in the Arctic: determining factors and quantification. Ecosystems. Valiela, I; Kinney, K; Culbertson, J; Peacock, E; Smith, S. Global losses of mangroves and salt marshes: Magnitudes, causes and consequences, in C. Duarte, ed. Global Loss of Coastal Habitats: Magnitudes, Causes, and Consequences. Fundacion BBVA. Madrid. Wookey, PA; Aerts, R; Bardgett, RD; Baptist, F; Bråthen, KA; Cornelissen, JHC; Gough, L; Hartley, IP; Hopkins, DW; Lavorel, S; Shaver, GR. Ecosystem feedbacks and cascade processes: understanding their role in the responses of arctic and alpine ecosystems to environmental change. Global Change Biology. 2008 Seminars February Elissa Schuett measures discharge at the Anaktuvak River in Alaska, the site of a fire that burned 256,000 acres in 2007. (Angela Allen) 19 Xosé (Xelu) Morán, Centro Oceanográfico de Xixón, Instituto Español de Oceanografía, “Carbon flux through bacterioplankton” 26 Johan (Joop) Varekamp, Wesleyan University, “Paleoenvironmental history of Long Island Sound” March 4 Kevin Griffin, LamontDoherty Earth Observatory, “Climate change and plant respiration: Mechanisms and implications” 18 Ken Foreman, MBL Ecosystems Center, “Innovative nutrient management strategies for Cape Cod estuaries: The science and policy of using permeable reactive barriers to remediate nitrate pollution” 25 Katherine Smith, Brown University, “U.S. live animal imports: 1.6 billion and climbing” April 1 Scott Doney, Woods Hole Oceanographic Institution, “Ocean acidification in a future high CO2 world” 8 Roman Stocker, MIT Department of Civil and Environmental Engineering. “Life in the microbial world: Making a living in a patchy ocean” 15 Jim Tang, MBL Ecosystems Center, “Agedriven decline of forest productivity and respiration: An ecological paradigm of succession revisited” 29 Wil Wolheim, University of New Hampshire, “Nutrient attenuation by river systems at watershed to global scales” May 6 Deborah Robertson, Clark University, “The evolution and regulation of nitrogen assimilation in marine algae: new surprises from old enzymes” 13 Colin Polsky, Clark University, “Reflections on the holy grail of integrating social and natural science: The case of climate, land use, and nutrient cycling in coastal zones” September 12 *Peter Ward, University of Washington, “Is past global warming in deep time a clue to the near future on Earth?” 16 Kathleen Savage, Woods Hole Research Center, “Deconstructing soil respiration response to environmental variables at varying temporal scales” 30 Peter Pollard, Australian Rivers Institute, School of Environmental Engineering, Griffith University, Australia “The missing carbon link: Terrestrial production meets aquatic microbial processes in freshwater ecosystems” October 7 Aaron M. Ellison, Harvard Forest, Harvard University “Detection and forecasting of thresholds in ecological systems: What do we need to know and when do we need to know it?” 14 Ruth Yanai, State University of New York, College of Environmental Science and Forestry, Syracuse, “What controls calcium depletion in northern hardwood ecosystems? Acid rain or aging forests?” November 4 Amy Lesen, Dillard University, “New Orleans preand post-Katrina: A US case study in coastal cities at risk. Ecology, culture, history, and vulnerability—What is the role of scientists?” 11 Zoe Cardon, MBL Ecosystems Center, “Hydraulic redistribution in a semi-arid Utah landscapemeasures, models, and microbes” 18 Jim Galloway, University of Virginia, “Food, feed and fuel: A story about nitrogen” 25 John Peterson, Oberlin College, “Buildings as ecological systems: Using realtime resource use feedback to foster understanding and stimulate conservation” 23 Edward Rastetter, MBL Ecosystems Center, “The PLIRTLE model, the Ensemble Kalman Filter, and CO2 fluxes from Arctic ecosystems” 21 Christopher Neill, MBL Ecosystems Center, “From coastal plain ponds to coastal sandplains: The implications of soil seed banks for conservation and restoration in two endangered ecosystems of Massachusetts” 26 *Steward Pickett, Cary Institute of Ecosystem Studies, “Urban ecology: Approach and insights as illustrated by the Baltimore Ecosystems Study Long-Term Ecological Research project” 24 *Ivette Perfecto, Dept. of Natural Resources and Environment, University of Michigan, “Special ecology in a coffee agroecosystem: Implications for biological control of pests and diseases” * SES Distinguished Scientist Seminar Series 31 *Ruth DeFries, Lamont Doherty Earth Observatory, Columbia University “Land use transitions in the tropics” December 2 Meredith Hastings, Brown University, “The biogeochemical-climate record: A new perspective on nitrate” 9 Adrian Rocha, MBL Ecosystems Center, “Burn severity influences post-fire surface energy and mass exchanges in arctic tundra” E c o s y s t e m s C e n t e r Report 2008 19 Scientists at the MBL Hugh W. Ducklow Senior Scientist, Co-Director Ph.D., Harvard University Kenneth H. Foreman Director of Semester in Environmental Science Ph.D., Boston University Hugh is a biological oceanographer focusing on the roles of bacteria in the ocean carbon cycle. His research in Antarctica looks at the responses of the continental shelf sea ice zone ecosystem to rapid climate warming. Ken’s principal research area is the coastal zone. In recent years, he has been studying the effects of nutrient loading on benthic and water column communities and processes. Jerry M. Melillo Senior Scientist, Co-Director Ph.D., Yale University Jerry is interested in how human activities are altering the biogeochemistry of terrestrial ecosystems and especially how global changes are affecting the chemistry of the atmosphere and the overall climate system. Zoe G. Cardon Senior Scientist Ph.D., Stanford University Zoe’s research focuses on microbial activity in soil around plant roots (the rhizosphere), including how water fluxes driven by plants affect resource availability, local conditions, and biogeochemistry in the rhizosphere. Linda A. Deegan Senior Scientist Ph.D., Louisiana State University Linda is interested in the relationship between animal populations and ecosystems because animals can strongly influence community composition and ecosystem nutrient cycles and productivity. 20 Ecosystems Center R e p o r t 2 0 0 8 Anne E. Giblin Senior Scientist Ph.D., Boston University Anne’s major research focus is the cycling of elements in the environment, especially the biogeochemistry of iron, sulfur, nitrogen and phosphorus in soils and sediments. Bruce J. Peterson Senior Scientist Ph.D., Cornell University Bruce focuses on understanding aquatic productivity and global change by studying the cycles of water, carbon and nitrogen at the ecosystem and global levels. Edward B. Rastetter Senior Scientist Ph.D., University of Virginia Ed synthesizes field and laboratory data using simulation models to study how plants and microbes optimize their use of resources like carbon, nitrogen, light and water, and how that optimization might influence the response of ecosystems to global change. Gaius R. Shaver Senior Scientist Ph.D., Duke University Gus’s research is focused on the role of plants in ecosystem element cycles, especially in Alaskan tundra ecosystems, where low temperatures, low light intensities, low nutrient availability, and a short growing season all interact to limit plant growth. Christopher Neill Associate Scientist Ph.D., University of Massachusetts, Amherst Chris investigates how ecosystems cycle nutrients and organic matter and how changes in land use, such as deforestation in the tropics, alter the structure and biogeochemistry of ecosystems. Jianwu (Jim) Tang Assistant Scientist Ph.D., University of California, Berkeley Jim’s research focuses on soil biogeochemistry and soil-plant interactions, particularly on carbon and nitrogen cycles through ecosystems processes. Joseph J. Vallino Associate Scientist Ph.D., Massachusetts Institute of Technology Joe’s research employs thermodynamics to examine how microbial metabolic networks organize and evolve to utilize energy and resources in the environment. Senior Staff Paul Colinvaux Senior Research Scientist Ph.D., Duke University John E. Hobbie Senior Scholar Ph.D., Indiana University Paul studies past climates and vegetation from the Amazon to the Arctic through analysis of air-borne pollen trapped in lake sediments. As an aquatic ecologist, John identifies the factors controlling decomposition and productivity in aquatic ecosystems, especially the role that microbes play. Adjunct Scientists Paul A. Steudler Senior Research Scholar M.S., University of Oklahoma Ivan Valiela Senior Research Scientist Boston University Ph.D., Cornell University Paul is interested in the responses of temperate and tropical forest and agricultural ecosystems to disturbances like hurricanes, nitrogen and sulfur additions, forest cutting and regrowth, and increased temperature. Ivan is interested in the coupling of land use on watersheds and coastal ecosystems in the larger context of global change. Postdoctoral Fellows Maureen H. Conte Adjunct Scientist in Residence Bermuda Institute of Ocean Sciences Ph.D., Columbia University Robert Howarth Cornell University Ph.D., Massachusetts Institute of Technology/Woods Hole Oceanographic Institution Maureen’s research speciality is trace level molecular and isotopic organic geochemistry. Research focus areas include deep ocean particle flux and the organic geochemistry of biogenic aerosols. Bob’s long-term interest is in environmental management and the effects of nutrients and pollutants on aquatic ecosystems. His scientific approach is through biogeochemistry, particularly nitrogen, phosphorus, and sulfur cycling and export from land to waters. Adrian V. Rocha Postdoctoral Scientist Ph.D., University of California, Irvine Sophia E. Fox Postdoctoral Scientist Ph.D., Boston University Sophia’s research focuses on examining mechanisms of landsea coupling and the effects of human activities on receiving coastal ecosystems, paricularly plant and animal community structure and food web relationships. Adrian’s research focuses on the biological and environmental controls on ecosystem exchanges of mass and energy at various temporal and spacial scales. Gabrielle Tomasky-Holmes Postdoctoral Scientist Ph.D., Boston University Gabby coordinates an Arctic Observations Network and analyzes carbon dioxide fluxes between tundra and atmosphere at several sites around the Arctic. E c o s y s t e m s C e n t e r Report 2008 21 Staff Staff Dorothy J. Berthel Administrative Assistant Donald W. Burnette Research Assistant M.S., Southern Illinois University Sarah M. Butler Research Assistant M.S., University of Maine Timothy Cronin Research Assistant B. A., Swarthmore College Matthew J. Erickson Senior Research Assistant M.S., University of WisconsinOshkosh Troy D. Hill Research Assistant M.S., Yale University Robert H. Garritt Senior Research Assistant M.S., Cornell University Melanie Hayn Research Assistant B.S., Cornell University Kelly R. Holzworth Research Administrator University of San Diego Samuel W. Kelsey Research Assistant B.S., Dickinson College David W. Kicklighter Research Associate M.S., University of Montana Bonnie L. Kwiatkowski Research Assistant M.S., University of New Hampshire James A. Laundre Senior Research Assistant M.S., University of Connecticut Christina Maki Research Assistant B.A., Bates College 22 Ecosystems Center R e p o r t 2 0 0 8 Richard P. McHorney Senior Research Assistant M.S., University of Pennsylvania Kate Morkeski Research Assistant M.S., Virginia Polytechnic Institute and State University Stephanie Oleksyk Research Assistant M.A., Clark University Marshall L. Otter Senior Research Assistant Ph.D., University of Cape Town Jennifer M. Peters Research Assistant B.A., Bard College Rebecca L. Prosser Research Assistant B.A., Earlham College Deborah G. Scanlon Projects and Publications Coordinator B.A., Syracuse University Elissa B. Schuett Research Assistant M.S., Frostburg State University Mary Ann Seifert Administrative Assistant B.A., Alfred University Suzanne M. Thomas Research Assistant M.S., University of Pennsylvania Jane Tucker Senior Research Assistant M.S., University of North Carolina Chelsea L. Vario Research Assistant B. S., University of New Hampshire J.C. Weber Senior Research Assistant M.S., University of Delaware Daniel J. White Research Assistant M.S., State University of New York at Brockport E c o s y s t e m s C e n t e r Report 2008 23 Graduate Students Brown-MBL Graduate Program in Biological and Environmental Sciences Shelby Hayhoe B.A. Grinnell College Advisors: Christopher Neill, Ecosystems Center Stephen Porder, Brown University Gillian L. Galford B.A., Washington University Yawei Luo M.S., Peking University Advisors: Hugh Ducklow, Ecosystems Center Warren Prell, Brown University Kristen M. S. Myers B.A., College of William and Mary Advisors: Hugh Ducklow, Ecosystems Center Jeremy Rich, Brown University Lindsay D. Brin B.A., Swarthmore College Advisors: Anne Giblin, Ecosystems Center Jeremy Rich, Brown University Ketil Koop-Jakobsen Ph.D. candidate, Boston University M.S., Roskilde University, Denmark Erin L. Kinney Ph.D. candidate, Boston University B.A., Dartmouth College Rita Oliveira Monteiro Ph.D candidate, SUNY ESF M.S., Université de Liège, Belgium Ylva Olsen Ph.D. candidate, Boston University M. S., University of Plymouth, UK Advisors: Jerry Melillo, Ecosystems Center Jack Mustard, Brown University Visiting Graduate Students Neil Bettez Ph.D. candidate, Cornell University M.S., University of North Carolina, Greensboro Consultants Staff who left in 2008 Francis P. Bowles, Research Systems Consultant Carlos E. P. Cerri Alina S. Cushing Heidi Golden Marselle Ozinskas-Alexander, Dean John A. Knauss Marine Policy Fellowship Angela Allen, Graduate Student, University of Alabama Jennifer S. Barkman, Graduate Student, University of Maryland Benjamin Felzer, Assistant Professor, Lehigh University Clara Funk, Graduate Student, University of Virginia Jennifer E. Johnson, Graduate Student, Stanford University Seeta Sistla, Graduate Student, University of California, Santa Barbara Aaron L. Strong, Technical Assistant, Massachusetts Institute of Technology Visiting Scientists and Scholars Peter Berg, University of Virginia Thomas Duncan, Nichols College James Galloway, University of Virginia Roxanne Marino, Cornell University Karen McGlathery, University of Virginia Xelu Morán, Instituto Español de Oceanografía Barbara Ondiviela, Universidad de Contrabria Yumei Zhou, Chinese Academy of Sciences 24 Ecosystems Center R e p o r t 2 0 0 8 Sources of Support for Research and Education T he annual operating budget of The Ecosystems Center for 2008 was $7,960,000. Approximately 71% of the income of the center comes from grants for basic research from government agencies, including the National Science Foundation, NASA, the Department of Energy and the Environmental Protection Agency. The other 29% comes from gifts and grants from private foundations, including support for the Semester in Environmental Science, as well as from institutional support for administration and income from the center’s reserve and endowment funds, and from the MBL. These non-governmental funds provide flexibility for the development of new research projects, public policy activities and educational programs. The combined total value of the center’s reserve fund and endowment at the end of 2008 was $3,320,000. Income from the reserve fund and endowment helps defray the costs of operations, writing proposals, consulting for government agencies and the center’s seminar program. The Ecosystems Center is grateful for the support it has received from the following corporations and foundations over the past five years: Arthur Vining Davis Foundation Blum-Kovler Foundation, Inc. The Clowes Fund, Inc. Harken Foundation Horizon Foundation, Inc. The Kohlberg Foundation, Inc. Massachusetts Environmental Trust Mayer & Morris Kaplan Family Foundation The Andrew W. Mellon Foundation The David and Lucile Packard Foundation The Harold Whitworth Pierce Charitable Trust The Sirius Fund The Starr Foundation Sugar, Friedberg and Felsenthal LLP Great Sippewissett Marsh, Falmouth, Massachusetts. (Ivan Valiela) Expenses Revenue 71% Government Grants 2% Private 12% MBL 11% Ecosystems Center Reserve Fund 4% Contributions 52% Personnel 21% Overhead 18% Operating 9% Subcontracts The Ecosystems Center MBL 7 MBL Street Woods Hole, MA 02543-1301 www.MBL.edu