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Articles 1 - 30 of 53
Full-Text Articles in Physical Sciences and Mathematics
Step-Wise Changes In Glacier Flow Speed Coincide With Calving And Glacial Earthquakes At Helheim Glacier, Greenland, M. Nettles, T. B. Larsen, P. Elósegui, Gordon S. Hamilton, Leigh A. Stearns, A. P. Ahlstrom, J. L. Davis, M. L. Andersen, J. De Juan, S. A. Khan, L. Stensing, G. Ekstrom, R. Forsberg
Step-Wise Changes In Glacier Flow Speed Coincide With Calving And Glacial Earthquakes At Helheim Glacier, Greenland, M. Nettles, T. B. Larsen, P. Elósegui, Gordon S. Hamilton, Leigh A. Stearns, A. P. Ahlstrom, J. L. Davis, M. L. Andersen, J. De Juan, S. A. Khan, L. Stensing, G. Ekstrom, R. Forsberg
Earth Science Faculty Scholarship
Geodetic observations show several large, sudden increases in flow speed at Helheim Glacier, one of Greenland's largest outlet glaciers, during summer, 2007. These step-like accelerations, detected along the length of the glacier, coincide with teleseismically detected glacial earthquakes and major iceberg calving events. No coseismic offset in the position of the glacier surface is observed; instead, modest tsunamis associated with the glacial earthquakes implicate glacier calving in the seismogenic process. Our results link changes in glacier velocity directly to calving-front behavior at Greenland's largest outlet glaciers, on timescales as short as minutes to hours, and clarify the mechanism by which …
Itase Synthesis Workshop, Paul Mayewski
Itase Synthesis Workshop, Paul Mayewski
University of Maine Office of Research Administration: Grant Reports
This award supports a workshop to bring together scientists involved in the International Trans-Antarctic Scientific Expedition (ITASE). Since 1999 the US has supported a program of traverses across both East and West Antarctica (US ITASE). US ITASE is part of the ITASE multi-national effort to understand the past 200-1000+ years of climate change over Antarctica and the Southern Ocean. ITASE is organized under the auspices of Scientific Committee for Antarctic Research (SCAR) and now comprises twenty-one countries. The international representatives from ITASE have met several times in the past to discuss national traverse plans; coordinate efforts; synthesize results; and develop …
Collaborative Research: Geophysical Evaluation Of Biogenic Gasses In Peatlands, Andrew S. Reeve
Collaborative Research: Geophysical Evaluation Of Biogenic Gasses In Peatlands, Andrew S. Reeve
University of Maine Office of Research Administration: Grant Reports
Biogenic gas emission from northern peatlands, by wicking from vascular plants and by episodic ebullition events, accounts for approximately 7% of the global annual emission of methane to the atmosphere. This proposal involves experiments to apply ground penetrating radar (GPR) for (1) estimating the amount of biogenic gas stored in peatlands, (2) determining the spatial distribution of biogenic gas within the peat, and (3) monitoring biogenic gas release to the atmosphere. Data from a large northern peatland in Maine (EAR-0242353) show that (1) higher CH4 and CO2 concentrations correlate with high velocity/high attenuation zones in cross-borehole GPR data as well …
Minerva 2008, The Honors College
Minerva 2008, The Honors College
Minerva
This issue of Minerva includes an article on the completion of the restoration of Colvin Hall; a reflection by Ruth Nadelhaft, former UMaine Honors program director; and an article on Honors alumnus and Nobel Peace Prize winner Bernard Lown and his 2008 Rezendes Visiting Scholar in Ethics Lecture/Distinguished Honors Graduate Lecture.
An Assessment Of Alternative Feed Ingredients In Practical Diets For Florida Pompano (Trachinotus Carolinus) Held In Low Salinity Recirculating Systems, Terhea Nichole Williams
An Assessment Of Alternative Feed Ingredients In Practical Diets For Florida Pompano (Trachinotus Carolinus) Held In Low Salinity Recirculating Systems, Terhea Nichole Williams
Electronic Theses and Dissertations
The identification of alternative protein sources for partial or whole replacement of fishmeal (FM) is a priority in the development of suitable, low cost feed formulations for the Florida pompano (Trachinotus carolinus). To evaluate alternative feed ingredients for the potential replacement of FM in diets fed to juvenile pompano, a series of four experiments were conducted. The objectives of Experiments 1 and 2 were to determine the apparent digestibility of crude protein (ADCP), energy (ADE), and apparent amino acid availability (AAAA) of three plant based ingredients (soybean meal (SBM), soy protein isolate (SPI), corn gluten meal (CGM)) and three by-product …
Collaborative Research: The Effect Of Iron-Complexing Ligands On Iron Availability To Phytoplankton In Hnlc Waters Of The Subarctic Pacific Ocean, Mark L. Wells, Mary Jane Perry, Charles Trick
Collaborative Research: The Effect Of Iron-Complexing Ligands On Iron Availability To Phytoplankton In Hnlc Waters Of The Subarctic Pacific Ocean, Mark L. Wells, Mary Jane Perry, Charles Trick
University of Maine Office of Research Administration: Grant Reports
Scientists from the University of Maine and San Francisco State University propose to do deck-board incubation experiments in high nutrient, low chlorophyll (HNLC) waters of the eastern (Ocean Station PAPA) and the western (Ocean Station KNOT) Subarctic Pacific Ocean to determine how Fe supply affects phytoplankton species composition. Specifically, this team of scientists plans to address the following specific objectives: (1) assess how the relative availability of Fe bound to weaker and stronger classes of ligands differs among different phytoplankton groups (cyanobacteria, diatoms, dinoflagellates, prymnesiophytes) and how these differences influence the evolution of the phytoplankton community after Fe enrichment in …
Tb200: Carbon And Nutrients In Maine Forest Soils, Ivan J. Fernandez
Tb200: Carbon And Nutrients In Maine Forest Soils, Ivan J. Fernandez
Technical Bulletins
Recent public concerns surrounding climate change and greenhouse gas emissions have resulted in a lively debate about approaches to fossil fuel offsets and carbon (C) sequestration in forests. The forest community sees opportunities for the intensification of the use of forests for markets ranging from forest products, such as fuel or fuel feedstock, to a range of new bioproducts. This report provides initial insights from an ongoing effort to synthesize forest soils data for Maine. The specific objectives presented here were (1) to develop descriptive statistics for C and measures of available forms of the essential nutrients N, P, and …
Saltwater Fishing In Cobscook Bay: Angler Profile And Economic Impact, Christopher Bartlett, Kevin Athearn Ph.D
Saltwater Fishing In Cobscook Bay: Angler Profile And Economic Impact, Christopher Bartlett, Kevin Athearn Ph.D
Maine Sea Grant Publications
This Research in Focus fact sheet profiles the economic impact of recreational fishing in Downeast Maine. Extension associate Chris Bartlett worked with University of Maine-Machias researcher Kevin Athearn to survey recreational fishers in the Cobscook Bay region. This research is informing sustainable development initiatives in Washington County.
Dry Valleys Late Holocene Climate Variability, Karl J. Kreutz, Paul Andrew Mayewski
Dry Valleys Late Holocene Climate Variability, Karl J. Kreutz, Paul Andrew Mayewski
University of Maine Office of Research Administration: Grant Reports
This award supports a project to collect and develop high-resolution ice core records from the Dry Valleys region of Antarctica, and provide interpretations of interannual to decadal-scale climate variability during the last 2000 years (late Holocene). The project will test hypotheses related to ocean/atmosphere teleconnections (e.g., El Nino Southern Oscillation, Antarctic Oscillation) that may be responsible for major late Holocene climate events such as the Little Ice Age in the Southern Hemisphere. Conceptual and quantitative models of these processes in the Dry Valleys during the late Holocene are critical for understanding recent climate changes, and represent the main scientific merit …
Us-Globec Nep Phase Iiia: Efffects Of Climate Variability On Calanus Dormancy Patterns And Population Dynamics Within The California Current, Jeffrey A. Runge
Us-Globec Nep Phase Iiia: Efffects Of Climate Variability On Calanus Dormancy Patterns And Population Dynamics Within The California Current, Jeffrey A. Runge
University of Maine Office of Research Administration: Grant Reports
Calanoid copepods are key organisms in the California Current (CC) region, consuming primary and secondary production at high rates and serving as prey for larval, juvenile, and small pelagic fish, other invertebrates and certain seabirds. A critical period in the life of several calanoid species is their overwintering period, during which they leave the unproductive surface waters in mid-summer to fall and then ascend to the surface in the springtime, usually coincident with the spring bloom. However, the physical and biological cues that both initiate and terminate the dormant phase of several key copepod species within the CC are poorly …
The Most Extensive Holocene Advance In The Stauning Alper, East Greenland, Occurred In The Little Ice Age, Brenda L. Hall, Carlo Baroni, George H. Denton
The Most Extensive Holocene Advance In The Stauning Alper, East Greenland, Occurred In The Little Ice Age, Brenda L. Hall, Carlo Baroni, George H. Denton
Earth Science Faculty Scholarship
We present glacial geologic and chronologic data concerning the Holocene ice extent in the Stauning Alper of East Greenland. The retreat of ice from the late-glacial position back into the mountains was accomplished by at least 11 000 cal years B.P. The only recorded advance after this time occurred during the past few centuries (the Little Ice Age). Therefore, we postulate that the Little Ice Age event represents the maximum Holocene ice extent in this part of East Greenland.
Foreword To The Special Issue: Arctic Palaeoclimate And Its Extremes (Apex), Martin Jakobsson, Robert F. Spielhagen, Jörn Thiede, Claus Andreasen, Brenda L. Hall, Ólafur Ingólfsson, Kurt H. Kjær, Thijs Van Kolfschoten, Gerhard Krinner, Antony Long, Juha-Pekka Lunkka, Dmitry Subetto, John Inge Svendsen
Foreword To The Special Issue: Arctic Palaeoclimate And Its Extremes (Apex), Martin Jakobsson, Robert F. Spielhagen, Jörn Thiede, Claus Andreasen, Brenda L. Hall, Ólafur Ingólfsson, Kurt H. Kjær, Thijs Van Kolfschoten, Gerhard Krinner, Antony Long, Juha-Pekka Lunkka, Dmitry Subetto, John Inge Svendsen
Earth Science Faculty Scholarship
No abstract provided.
Recommended Nomenclature For The Sapphirine And Surinamite Groups (Sapphirine Supergroup), Edward S. Grew, U. Hålenius, M. Pasero, J. Barbier
Recommended Nomenclature For The Sapphirine And Surinamite Groups (Sapphirine Supergroup), Edward S. Grew, U. Hålenius, M. Pasero, J. Barbier
Earth Science Faculty Scholarship
Minerals isostructural with sapphirine-1A, sapphirine-2M, and surinamite are closely related chain silicates that pose nomenclature problems because of the large number of sites and potential constituents, including several (Be, B, As, Sb) that are rare or absent in other chain silicates. Our recommended nomenclature for the sapphirine group (formerly-aenigmatite group) makes extensive use of precedent, but applies the rules to all known natural compositions, with flexibility to allow for yet undiscovered compositions such as those reported in synthetic materials. These minerals are part of a polysomatic series composed of pyroxene or pyroxene-like and spinel modules, and thus we recommend that …
Synthesis And Oxidation Of Lignin-Carbohydrate Model Compounds, Mai Thanh Thi Nguyen
Synthesis And Oxidation Of Lignin-Carbohydrate Model Compounds, Mai Thanh Thi Nguyen
Electronic Theses and Dissertations
To decrease our dependence on foreign oil supply and in an effort to decrease the amount of green house gases into the atmosphere, researchers are focusing on ways of producing fuels and chemicals from renewable resources. A renewable source such as wood has great potential for the production of biofuels and biochemicals. An integrated biorefinery process that maximizes the usage of wood and complements existing pulp and paper technology was proposed to extract underutilize hemicelluloses and covert them into bioethanol. In this process, not only hemicelluloses are extracted; lignin, since it is covalently bonded to hemicelluloses is extracted as well. …
Effects Of Fish Introductions On The Geographic Distribution And Native Invertebrate Biodiversity Of Naturally Fishless Lakes In Maine, Emily Gaenzle Schilling
Effects Of Fish Introductions On The Geographic Distribution And Native Invertebrate Biodiversity Of Naturally Fishless Lakes In Maine, Emily Gaenzle Schilling
Electronic Theses and Dissertations
Widespread fish stocking has led to a worldwide decline in naturally fishless lakes and their associated communities. Little is known about the historical distribution or native communities of these freshwater ecosystems. The objectives of this study were to: 1) develop a quantitative method to remotely detect naturally fishless lakes in Maine, 2) conduct a landscape-scale assessment of unique attributes of fishless lake macroinvertebrate communities, 3) identify macroinvertebrate bioindicators of fish absence, and 4) assess effects of introduced fish on native macroinvertebrates. I identified two physiographic types of naturally fishless lakes in Maine: kettle lakes in the eastern lowlands and foothills …
Alps Implementation Conference, Mary Jane Perry
Alps Implementation Conference, Mary Jane Perry
University of Maine Office of Research Administration: Grant Reports
Intellectual Merit:
A diverse suite of autonomous mobile platforms - including drifters, floats, underwater gliders and AUVs (autonomous underwater vehicles), and the small sensors they carry - have collectively become known as ALPS, i.e., "Autonomous and Lagrangian Platforms and Sensors". A small interdisciplinary workshop is proposed as a follow-on to the Spring 2003 ALPS workshop. The first ALPS workshop convened a group of scientists and engineering, representing diverse backgrounds and interests, who met to identify new science that could best be done with ALPS alone or in conjunction with other platforms; to address technological developments needed to improve the capabilities …
Study Targets Striped Bass, Catherine V. Schmitt
Study Targets Striped Bass, Catherine V. Schmitt
Maine Sea Grant Publications
This article in the Bangor Daily News profiles the Sea Grant-funded research of Dr. Joe Zydlewski, who is studying the striped bass population in the Penobscot River. A must read for all striper fans.
The Use Of Ships' Protests For Reconstruction Of Synoptic-Scale Weather And Tropical Storm Identification In The Late Eighteenth Century, Louis K. Mcnally, Kirk A. Maasch, Kimberly A. Zuill
The Use Of Ships' Protests For Reconstruction Of Synoptic-Scale Weather And Tropical Storm Identification In The Late Eighteenth Century, Louis K. Mcnally, Kirk A. Maasch, Kimberly A. Zuill
Earth Science Faculty Scholarship
Ships’ protests have been used for centuries as legal documents to record and detail damages and indemnify Captains from fault. We use them in this article, along with data extracted through forensic synoptic analysis (McNally, 1994, 2004) to identify a tropical or subtropical system in the North Atlantic Ocean in 1785. They are shown to be viable sources of meteorological information. By comparing a damaging storm in New England in 1996, which included an offshore tropical system, with one reconstructed in 1785, we demonstrate that the tropical system identified in a ship’s protest played a significant role in the 1785 …
Chopinite-Sarcopside Solid Solution, (Mg, Fe)(3) (Po(4))(2), In Lodranite Gra 95209, Edward S. Grew, Martin G. Yates, R. J. Beane, C. Floss, Christopher Gerbi
Chopinite-Sarcopside Solid Solution, (Mg, Fe)(3) (Po(4))(2), In Lodranite Gra 95209, Edward S. Grew, Martin G. Yates, R. J. Beane, C. Floss, Christopher Gerbi
Earth Science Faculty Scholarship
No abstract provided.
Interpretation Of The High Resolution, Multivariate Mt. Logan (Yukon Territory) Ice Core - A Record Of North Pacific Climate And Atmospheric Chemistry, Paul Andrew Mayewski
Interpretation Of The High Resolution, Multivariate Mt. Logan (Yukon Territory) Ice Core - A Record Of North Pacific Climate And Atmospheric Chemistry, Paul Andrew Mayewski
University of Maine Office of Research Administration: Grant Reports
The recently developed Mt. Logan ice core glaciochemical dataset provides an unprecedented opportunity to understand Holocene climate change and the sources and fluxes of natural and anthropogenic chemicals in the North Pacific atmosphere. The 185 m-long ice core has been sampled at very high resolution using a refined and updated continuous ice core melter system, and analyzed for over 40 chemical species, including major ions, trace elements, rare earth elements, and stable isotopes. Subseasonal samples spanning the top ~500 years allow for annual layer counting, followed by ice flow modeling for the remainder of the timescale spanning the Holocene and …
Three Years Of Ocean Data From A Bio-Optical Profiling Float, Emmanuel Boss, Mary Jane Perry, Dana Swift, Lisa Taylor, Peter Brickley, J. Ron V. Zaneveld, Stephen Riser
Three Years Of Ocean Data From A Bio-Optical Profiling Float, Emmanuel Boss, Mary Jane Perry, Dana Swift, Lisa Taylor, Peter Brickley, J. Ron V. Zaneveld, Stephen Riser
Marine Sciences Faculty Scholarship
Ocean color, first measured from space 30 years ago, has provided a revolutionary synoptic view of near-surface fields of phytoplankton pigments. Since 1979, a number of ocean color satellite missions have provided coverage of phytoplankton biomass and other biogeochemical variables on scales of days to years and of kilometers to ocean basin. Because of the nature of visible light and its interaction with absorbing and scattering materials in the ocean and atmosphere, these measurements are biased toward nearsurface waters and are obscured by clouds. As a consequence, ocean color satellites miss significant fractions of phytoplankton biomass, marine primary productivity, and …
Primary Oil Migration Through Buoyancy-Driven Multiple Fracture Propagation: Oil Velocity And Flux, Z.-H. Jin, Scott E. Johnson
Primary Oil Migration Through Buoyancy-Driven Multiple Fracture Propagation: Oil Velocity And Flux, Z.-H. Jin, Scott E. Johnson
Earth Science Faculty Scholarship
We present a fracture-mechanics-based formulation to investigate primary oil migration through the propagation of an array of periodic, parallel fractures in a sedimentary rock with elevated pore fluid pressure. The rock is assumed to be a linearly elastic medium. The fracture propagation and hence oil migration velocity are determined using a fracture mechanics criterion together with the lubrication theory of fluid mechanics. We find that fracture interactions have profound effects on the primary oil migration behavior. For a given fracture length, the mass flux of oil migration decreases dramatically with an increase in fracture density. The reduced oil flux is …
Alewives: Feast Of The Season, Catherine V. Schmitt
Alewives: Feast Of The Season, Catherine V. Schmitt
Maine Sea Grant Publications
Alewives are sea-run, or diadromous, fish that spend most of their lives in the Atlantic Ocean but return as adults to coastal rivers in spring to spawn in freshwater streams and ponds. This article in Maine Boats, Homes, & Harbors magazine discusses the natural and cultural history of Maine's native runs of alewives and other sea-run fish.
A Paleolimnological Assessment Of Three Oligotrophic Watersheds In Maine, Tiffany Ann Wilson
A Paleolimnological Assessment Of Three Oligotrophic Watersheds In Maine, Tiffany Ann Wilson
Electronic Theses and Dissertations
Phosphorus (P) is a limiting nutrient in aquatic ecosystems. Its bioavailability determines the trophic status of lakes. The biogeochemistry of P in surface waters can be controlled by a combination of abiotic and biotic factors. Dissolved inorganic aluminum (Al) and iron (Fe) hydrolyze in streams and lakes to produce Al(OH)3 and Fe(OH)3 in the water column. These hydroxides may also form through photo-oxidation of complexes with DOC, liberation of inorganic metal species, and precipitation, followed by sedimentation. These solid phases readily adsorb P from the water column, reducing the amount that is available for biological nutrition (Kopácek et …
Three-Dimensional Modeling Of Continental Subduction And The Evolution Of Ultra High Pressure Metamorphism, Peter O. Koons
Three-Dimensional Modeling Of Continental Subduction And The Evolution Of Ultra High Pressure Metamorphism, Peter O. Koons
University of Maine Office of Research Administration: Grant Reports
This project investigates driving forces and material behavior associated with continental subduction and ultra high-pressure metamorphism through an integration of numerical modeling of continental subduction and structural/petrological evolution of the material caught in the collision. The natural ultra high-pressure and high-pressure assemblages of the Western Gneiss of Norway provide rheological, geometric and geochronological information for the modeling, while the active obliquely convergent plate boundary of central New Zealand serves as a modern analog of a collision-subduction transition. Continental subduction zones represent regions where the crust-mantle interaction changes from nearly horizontal to dominantly vertical, accentuating the competing influences of body and …
Collaborative Research: Research On The Learning And Teaching Of Thermal Physics, John R. Thompson
Collaborative Research: Research On The Learning And Teaching Of Thermal Physics, John R. Thompson
University of Maine Office of Research Administration: Grant Reports
Groups at Iowa State University and the University of Maine will collaborate in a coordinated program of research and research-based curriculum development in thermal physics, targeting both introductory general physics courses and advanced-level undergraduate courses. The research component involves one-on-one student interviews, written pre- and post-test questions, and multiple-choice surveys. This research is then applied to the development of curricular materials intended to improve student understanding in a manner consistent with active-learning methods previously shown be effective in physics instruction. The curriculum will in turn be evaluated for its effectiveness at addressing the student difficulties previously identified through research.
This …
Ice Core Record Of Rising Lead Pollution In The North Pacific Atmosphere, E. Osterberg, Paul Andrew Mayewski, Karl J. Kreutz, D. Fisher, M. Handley, Sharon B. Sneed, C. Zdanowicz, J. Zheng, M. Demuth, M. Waskiewicz, J. Bourgeois
Ice Core Record Of Rising Lead Pollution In The North Pacific Atmosphere, E. Osterberg, Paul Andrew Mayewski, Karl J. Kreutz, D. Fisher, M. Handley, Sharon B. Sneed, C. Zdanowicz, J. Zheng, M. Demuth, M. Waskiewicz, J. Bourgeois
Earth Science Faculty Scholarship
A high-resolution, 8000 year-long ice core record from the Mt. Logan summit plateau (5300 m asl) reveals the initiation of trans-Pacific lead (Pb) pollution by ca. 1730, and a > 10-fold increase in Pb concentration (1981-1998 mean = 68.9 ng/l) above natural background (5.6 ng/l) attributed to rising anthropogenic Pb emissions from Asia. The largest rise in North Pacific Pb pollution from 1970-1998 (end of record) is contemporaneous with a decrease in Eurasian and North American Pb pollution as documented in ice core records from Greenland, Devon Island, and the European Alps. The distinct Pb pollution history in the North Pacific …
Magma-Driven Multiple Dike Propagation And Fracture Toughness Of Crustal Rocks, Z.-H. Jin, Scott E. Johnson
Magma-Driven Multiple Dike Propagation And Fracture Toughness Of Crustal Rocks, Z.-H. Jin, Scott E. Johnson
Earth Science Faculty Scholarship
Dike swarms consisting of tens to thousands of subparallel dikes are commonly observed at Earth's surface, raising the possibility of simultaneous propagation of two or more dikes at various stages of a swarm's development. The behavior of multiple propagating dikes differs from that of a single dike owing to the interacting stress fields associated with each dike. We analyze an array of parallel, periodically spaced dikes that grow simultaneously from an overpressured source into a semi-infinite, linear elastic host rock. To simplify the analysis, we assume steady state (constant velocity) magma flow and dike propagation. We use a perturbation method …
(Rcn) Terrestrial Ecosystem Response To Atmospheric And Climatic Change, Lindsey E. Rustad
(Rcn) Terrestrial Ecosystem Response To Atmospheric And Climatic Change, Lindsey E. Rustad
University of Maine Office of Research Administration: Grant Reports
Future changes in the global carbon balance and associated feedbacks to climate will depend on ecosystem responses to multiple, interacting drivers of global change, such as elevated CO2, temperature, N deposition and changes in the amount and timing of precipitation. Efforts to predict these interactions with modeling approaches have been limited by a lack of relevant experimental data, as well as the absence of mechanisms for rapid communication between modelers and experimentalists. This grant will establish a network of global change scientists in an initiative on Terrestrial Ecosystem Responses to Atmospheric and Climatic Change (TERACC), with the aim to (1) …
Seasonal Geophysical Monitoring Of Biogenic Gases In A Northern Peatland: Implications For Temporal And Spatial Variability In Free Phase Gas Production Rates, Xavier Comas, Lee Slater, Andrew S. Reeve
Seasonal Geophysical Monitoring Of Biogenic Gases In A Northern Peatland: Implications For Temporal And Spatial Variability In Free Phase Gas Production Rates, Xavier Comas, Lee Slater, Andrew S. Reeve
Earth Science Faculty Scholarship
A set of high resolution surface ground penetrating radar (GPR) surveys, combined with elevation rod ( to monitor surface deformation) and gas flux measurements, were used to investigate in situ biogenic gas dynamics within a northern peatland (Caribou Bog, Maine). Gas production rates were directly estimated from the time series of GPR measurements. Spatial variability in gas production was also investigated by comparing two sites with different geological and ecological attributes, showing differences and/or similarities depending on season. One site characterized by thick highly humified peat deposits (5-6 m), wooded heath vegetation and open pools showed large ebullition events during …