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The Road To The Model T: Culture, Road Conditions, And Innovation At The Dawn Of The American Motor Age, Christopher W. Wells Jun 2007

The Road To The Model T: Culture, Road Conditions, And Innovation At The Dawn Of The American Motor Age, Christopher W. Wells

Faculty Publications

No abstract provided.

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Timescale Dependence Of Environmental And Plant‐Mediated Controls On Ch4 Flux In A Temperate Fen, Claire C. Treat, Jill L. Bubier, Ruth K. Varner, Patrick M. Crill Feb 2007

Timescale Dependence Of Environmental And Plant‐Mediated Controls On Ch4 Flux In A Temperate Fen, Claire C. Treat, Jill L. Bubier, Ruth K. Varner, Patrick M. Crill

Faculty Publications

This study examined daily, seasonal, and interannual variations in CH4 emissions at a temperate peatland over a 5‐year period. We measured net ecosystem CO2 exchange (NEE), CH4 flux, water table depth, peat temperature, and meteorological parameters weekly from the summers (1 May to 31 August) of 2000 through 2004 at Sallie's Fen in southeastern New Hampshire, United States. Significant interannual differences, driven by high variability of large individual CH4 fluxes (ranging from 8.7 to 3833.1 mg CH4 m−2 d−1) occurring in the late summer, corresponded with a decline in water table level and an increase in air and peat temperature. …

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Importance Of The Mixed-Phase Cloud Distribution In The Control Climate For Assessing The Response Of Clouds To Carbon Dioxide Increase: A Multi-Model Study, Yoko Tsushima, S. Emori, T. Ogura, M. Kimoto, M. J. Webb, K. D. Williams, M. A. Ringer, B. J. Soden, B. Li, N. Andronova Aug 2006

Importance Of The Mixed-Phase Cloud Distribution In The Control Climate For Assessing The Response Of Clouds To Carbon Dioxide Increase: A Multi-Model Study, Yoko Tsushima, S. Emori, T. Ogura, M. Kimoto, M. J. Webb, K. D. Williams, M. A. Ringer, B. J. Soden, B. Li, N. Andronova

Faculty Publications

We have conducted a multi-model intercomparison of cloud-water in five state-of-the-art AGCMs run for control and doubled carbon dioxide climates. The most notable feature of the differences between the control and doubled carbon dioxide climates is in the distribution of cloud-water in the mixed-phase temperature band. The difference is greatest at mid and high latitudes. We found that the amount of cloud ice in the mixed phase layer in the control climate largely determines how much the cloud-water distribution changes for the doubled carbon dioxide climate. Therefore evaluation of the cloud ice distribution by comparison with data is important for …

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Species-Habitat Associations In A Sri Lankan Dipterocarp Forest, C. V.S. Gunatilleke, I. A.U.N. Gunatilleke, S. Esufali, K. E. Harms, P. M.S. Ashton, D. F.R.P. Burslem, P. S. Ashton Jul 2006

Species-Habitat Associations In A Sri Lankan Dipterocarp Forest, C. V.S. Gunatilleke, I. A.U.N. Gunatilleke, S. Esufali, K. E. Harms, P. M.S. Ashton, D. F.R.P. Burslem, P. S. Ashton

Faculty Publications

Forest structure and species distribution patterns were examined among eight topographically defined habitats for the 205 species with stems ≥ 1 cm dbh inhabiting a 25-ha plot in the Sinharaja rain forest, Sri Lanka. The habitats were steep spurs, less-steep spurs, steep gullies and less-steep gullies, all at either lower or upper elevations. Mean stem density was significantly greater on the upper spurs than in the lower, less-steep gullies. Stem density was also higher on spurs than in gullies within each elevation category and in each upper-elevation habitat than in its corresponding lower-elevation habitat. Basal area varied less among habitats, …

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Growth, Feeding And Reproduction Of The Catfish Eremophilus Mutisii (Pisces : Trichomycteridae), From Artificial Reservoirs In Colombia, Gabriel Pinilla, Maritza Abril, Esperanza González Jun 2006

Growth, Feeding And Reproduction Of The Catfish Eremophilus Mutisii (Pisces : Trichomycteridae), From Artificial Reservoirs In Colombia, Gabriel Pinilla, Maritza Abril, Esperanza González

Faculty Publications

The catfish, Eremophilus mutisii, was cultured under different densities in artificial rainfall reservoirs at Caldas, Boyaca, Colombia. At capture, the average total length of the animals was 10 cm and the weight ranged between 9 and 10 g. These fish were in initial stages of sexual development. After a year in the reservoirs, they had increased in length and weight as follows (densities in parentheses): 5.22 cm and 27.23 g (0.5 individuals/m(2))); 1.98 cm and 8.79 g (1 individual/m(2)), and 2.45 cm and 0.82 g (2 individuals/m(2)). They were at the early stages of sexual maturity, and their condition …

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Comparing The Direct And Community-Mediated Effects Of Disturbance On Plant Population Dynamics: Flooding, Herbivory And Mimulus Guttatus, Bret D. Elderd, Dan F. Doak May 2006

Comparing The Direct And Community-Mediated Effects Of Disturbance On Plant Population Dynamics: Flooding, Herbivory And Mimulus Guttatus, Bret D. Elderd, Dan F. Doak

Faculty Publications

Competition, trophic interactions and abiotic disturbances play important roles in governing plant population dynamics, yet few studies have addressed their relative contributions or interacting effects. We used Life Table Response Experiment (LTRE) analysis, coupled with stochastic analyses, to examine how a major abiotic disturbance, flooding, influences the fitness and population growth of a common riparian plant, Mimulus guttatus, and how this effect compares and interacts with that exerted by herbivory. We also extended LTRE analysis to include nested factors, which enabled us to examine differences across experimental sites. These spatial contributions to changes in population growth rate, λ, were compared …

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Disturbance-Mediated Trophic Interactions And Plant Performance, Bret D. Elderd Mar 2006

Disturbance-Mediated Trophic Interactions And Plant Performance, Bret D. Elderd

Faculty Publications

Disturbances, such as flooding, play important roles in determining community structure. Most studies of disturbances focus on the direct effects and, hence, the indirect effects of disturbances are poorly understood. Within terrestrial riparian areas, annual flooding leads to differences in the arthropod community as compared to non-flooded areas. In turn, these differences are likely to alter the survival, growth, and reproduction of plant species via an indirect effect of flooding (i.e., changes in herbivory patterns). To test for such effects, an experiment was conducted wherein arthropod predators and herbivores were excluded from plots in flooded and non-flooded areas and the …

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Nonrandom Processes Maintain Diversity In Tropical Forests, Christopher Wills, Kyle E. Harms, Richard Condit, David King, Jill Thompson, Fangliang He, Helene C. Muller-Landau, Peter Ashton, Elizabeth Losos, Liza Comita, Stephen Hubbell, James Lafrankie, Sarayudh Bunyavejchewin, H. S. Dattaraja, Stuart Davies, Shameema Esufali, Robin Foster, Nimal Gunatilleke, Savitri Gunatilleke, Pamela Hall, Akira Itoh, Robert John, Somboon Kiratiprayoon, Suzanne Loo De Lao, Marie Massa, Cheryl Nath, Md Nur Supardi Noor, Abdul Rahman Kassim, Raman Sukumar, Hebbalalu Satyanarayana Suresh, I. Fang Sun, Sylvester Tan, Takuo Yamakura Jan 2006

Nonrandom Processes Maintain Diversity In Tropical Forests, Christopher Wills, Kyle E. Harms, Richard Condit, David King, Jill Thompson, Fangliang He, Helene C. Muller-Landau, Peter Ashton, Elizabeth Losos, Liza Comita, Stephen Hubbell, James Lafrankie, Sarayudh Bunyavejchewin, H. S. Dattaraja, Stuart Davies, Shameema Esufali, Robin Foster, Nimal Gunatilleke, Savitri Gunatilleke, Pamela Hall, Akira Itoh, Robert John, Somboon Kiratiprayoon, Suzanne Loo De Lao, Marie Massa, Cheryl Nath, Md Nur Supardi Noor, Abdul Rahman Kassim, Raman Sukumar, Hebbalalu Satyanarayana Suresh, I. Fang Sun, Sylvester Tan, Takuo Yamakura

Faculty Publications

An ecological community's species diversity tends to erode through time as a result of stochastic extinction, competitive exclusion, and unstable host-enemy dynamics. This erosion of diversity can be prevented over the short term if recruits are highly diverse as a result of preferential recruitment of rare species or, alternatively, if rare species survive preferentially, which increases diversity as the ages of the individuals increase. Here, we present census data from seven New and Old World tropical forest dynamics plots that all show the latter pattern. Within local areas, the trees that survived were as a group more diverse than those …

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Mapping Height And Biomass Of Mangrove Forests In Everglades National Park With Srtm Elevation Data, Marc Simard, Keqi Zhang, Victor H. Rivera-Monroy, Michael S. Ross, Pablo L. Ruiz, Edward Castañeda-Moya, Robert R. Twilley, Ernesto Rodriguez Jan 2006

Mapping Height And Biomass Of Mangrove Forests In Everglades National Park With Srtm Elevation Data, Marc Simard, Keqi Zhang, Victor H. Rivera-Monroy, Michael S. Ross, Pablo L. Ruiz, Edward Castañeda-Moya, Robert R. Twilley, Ernesto Rodriguez

Faculty Publications

We produced a landscape scale map of mean tree height in mangrove forests in Everglades National Park (ENP) using the elevation data from the Shuttle Radar Topography Mission (SRTM). The SRTM data was calibrated using airborne lidar data and a high resolution USGS digital elevation model (DEM). The resulting mangrove height map has a mean tree height error of 2.0 m (RMSE) over a pixel of 30 m. In addition, we used field data to derive a relationship between mean forest stand height and biomass in order to map the spatial distribution of standing biomass of mangroves for the entire …

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The Benefits Of A For-Credit Course For New Writing Center Staff, Richard Benjamin Crosby Jan 2006

The Benefits Of A For-Credit Course For New Writing Center Staff, Richard Benjamin Crosby

Faculty Publications

Some questions about writing center theory and praxis never seem to change: how do we prepare for our clientele? How do we engage them? What questions should we ask? When should we direct them? And when should we encourage them to direct us? The list goes on. Fortunately, we consider it a virtue that we continue interrogating the same issues. As students of rhetoric, we realize that the answers to these questions often depend on the contexts in which they are asked. Thus, we give ourselves over to principles of adaptability. Instead of establishing rigid, universal rules that do not …

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New Orleans, The Chesapeake, And The Future Of Environmental Assessment: Overcoming The Natural Resources Law Of Unintended Consequences, Erin Ryan Jan 2006

New Orleans, The Chesapeake, And The Future Of Environmental Assessment: Overcoming The Natural Resources Law Of Unintended Consequences, Erin Ryan

Faculty Publications

No abstract provided.

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Comment On "El Niño Suppresses Antarctic Warming" By N. Bertler Et Al, Peter T. Doran, John C. Priscu, W. Berry Lyons, John E. Walsh, Andrew G. Fountain, Diane M. Mcknight, Daryl L. Moorhead, Ross A. Virginia, Diana H. Wall, Gary D. Clow, Christian H. Fritsen, Christopher P. Mckay, Andrew N. Parsons Apr 2005

Comment On "El Niño Suppresses Antarctic Warming" By N. Bertler Et Al, Peter T. Doran, John C. Priscu, W. Berry Lyons, John E. Walsh, Andrew G. Fountain, Diane M. Mcknight, Daryl L. Moorhead, Ross A. Virginia, Diana H. Wall, Gary D. Clow, Christian H. Fritsen, Christopher P. Mckay, Andrew N. Parsons

Faculty Publications

No abstract provided.

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Christian Environmentalism: Cosmos, Community, And Place, John R. Wood, Janel Curry, Steven C. Bouma-Prediger, Mark Bjelland, Susan P. Bratton Mar 2005

Christian Environmentalism: Cosmos, Community, And Place, John R. Wood, Janel Curry, Steven C. Bouma-Prediger, Mark Bjelland, Susan P. Bratton

Faculty Publications

No abstract provided.

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New Standards For Reducing Gravity Data: The North American Gravity Database, William J. Hinze, Carlos Aiken, John Brozena, Bernard Coakley, David Dater, Guy Flanagan, Rene Forsberg, Thomas Hildenbrand, G. Randy Keller, James N. Kellogg, Robert Kucks, Xiong Li, Andre Mainville, Robert Morin, Mark Pilkington, Donald Plouff, Dhananjay Ravat, Daniel Roman, Jamie Urrutia-Fucugauchi, Marc Veronneau, Michael Webring, Daniel Winester Jan 2005

New Standards For Reducing Gravity Data: The North American Gravity Database, William J. Hinze, Carlos Aiken, John Brozena, Bernard Coakley, David Dater, Guy Flanagan, Rene Forsberg, Thomas Hildenbrand, G. Randy Keller, James N. Kellogg, Robert Kucks, Xiong Li, Andre Mainville, Robert Morin, Mark Pilkington, Donald Plouff, Dhananjay Ravat, Daniel Roman, Jamie Urrutia-Fucugauchi, Marc Veronneau, Michael Webring, Daniel Winester

Faculty Publications

The North American gravity database as well as databases from Canada, Mexico, and the United States are being revised to improve their coverage, versatility, and accuracy. An important part of this effort is revising procedures for calculating gravity anomalies, taking into account our enhanced computational power, improved terrain databases and datums, and increased interest in more accurately defining long-wavelength anomaly components. Users of the databases may note minor differences between previous and revised database values as a result of these procedures. Generally, the differences do not impact the interpretation of local anomalies but do improve regional anomaly studies. The most …

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Multiplicative Renormalization And Generating Functions Ii, Nobuhiro Asai, Izumi Kubo, Hui Hsiung Kuo Jan 2004

Multiplicative Renormalization And Generating Functions Ii, Nobuhiro Asai, Izumi Kubo, Hui Hsiung Kuo

Faculty Publications

Let μ be a probability measure on the real line with finite moments of all orders. Suppose the linear span of polynomials is dense in L 2(μ). Then there exists a sequence {Pn} n=0∞ orthogonal polynomials with respect to μ such that Pn is a polynomial of degree n with leading coefficient 1 and the equality (x -αn)Pn(x) = Pn+1(x) + wnPn-1(x) holds, where αn and w n are Szegö-Jacobi parameters. In this paper we use the concepts of pre-generating function, multiplicative renormalization, and generating function to derive {Pn,αn,wn} from a given μ Two types of pre-generating functions are studied. …

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Content Analysis Of The Leading General Academic Databases, Kelly D. Blessinger, Maureen Olle-Lajoie Jan 2004

Content Analysis Of The Leading General Academic Databases, Kelly D. Blessinger, Maureen Olle-Lajoie

Faculty Publications

Title lists from the three leading general academic databases were compared to evaluate journal content. Some of the elements that were analyzed include subject coverage, the quality of titles provided, accessibility issues, and trends over time for these databases. While database title lists are now readily available on the Internet for comparison, as our article illustrates, these lists need further evaluation for proper assessment.

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Regulating Genetically Modified Foods: Is Mandatory Labeling The Right Answer?, Jonathan H. Adler Jan 2004

Regulating Genetically Modified Foods: Is Mandatory Labeling The Right Answer?, Jonathan H. Adler

Faculty Publications

What I want to talk about are some legal issues relating to labeling and, in particular, constitutional issues relating to mandatory labeling for genetically modified foods or food products that may contain genetically modified components. This is a separate issue from whether or not the FDA, or some other agency, has sufficient statutory authority at present to mandate labeling, and that is something worth discussing. Even if they do have such authority, or even if Congress tomorrow were to give the FDA such authority or were to require the FDA to impose labels on genetically modified foods, or if a …

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Teaching Green: Experimenting With Green Values In The Classroom, David Whiteman Jan 2003

Teaching Green: Experimenting With Green Values In The Classroom, David Whiteman

Faculty Publications

No abstract provided.

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Snow-Patch Influence On Soil Biogeochemical Processes And Invertebrate Distribution In The Mcmurdo Dry Valleys, Antarctica, Michael N. Gooseff, J. E. Barrett, Peter T. Doran, Andrew G. Fountain, W. Berry Lyons, Andrew N. Parsons, Dorota L. Porazinska, Ross A. Virginia, Diana H. Wall Jan 2003

Snow-Patch Influence On Soil Biogeochemical Processes And Invertebrate Distribution In The Mcmurdo Dry Valleys, Antarctica, Michael N. Gooseff, J. E. Barrett, Peter T. Doran, Andrew G. Fountain, W. Berry Lyons, Andrew N. Parsons, Dorota L. Porazinska, Ross A. Virginia, Diana H. Wall

Faculty Publications

The McMurdo Dry Valleys is the largest of the ice-free areas in Antarctica. Precipitation events in excess of 1 cm of snow accumulation are rare. During the winter, snow is transported by strong katabatic winds blowing from the polar plateau, and deposited into the lee of topographic features (e.g., stream channels and other topographic depressions). At the start of the austral summer (early October), as much as 10% of the valley soils may be covered by distributed snow patches. Because liquid water is the primary driver of biological, physical, and chemical processes in this polar desert, quantifying fluxes of water …

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Recent Applications Of Flame Atomic Absorption Spectrometry To Environmental Measurements, Michael A. Janusa Jan 2002

Recent Applications Of Flame Atomic Absorption Spectrometry To Environmental Measurements, Michael A. Janusa

Faculty Publications

Atomic absorption spectroscopy is very useful for the determination of a large number of elements, especially at trace levels. It is a widely used technique for analysis of a wide variety of sample matrices including biota, soils, and water. Atomic absorption spectroscopy is a very reputable technique that is inexpensive and delivers accurate results even in a complex matrix. This review focuses on the applications of flame atomic absorption spectroscopy to environmental measurements, and is mainly based on papers published from 1999–2002.

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Differential Detection Of Bartonella Species And Strains In Cat Scratch Disease Diagnostics By Polymerase Chain Reaction Amplification Of 16s Ribosomal Rna Gene, Ronald A. Tapp, Alma F. Roy, Richard E. Corstvet, Vincent L. Wilson Jan 2001

Differential Detection Of Bartonella Species And Strains In Cat Scratch Disease Diagnostics By Polymerase Chain Reaction Amplification Of 16s Ribosomal Rna Gene, Ronald A. Tapp, Alma F. Roy, Richard E. Corstvet, Vincent L. Wilson

Faculty Publications

Cat scratch disease (CSD) has been difficult to diagnose in animals because of the protracted clinical course of infection and the quiescent phases when the microbial culprit lies dormant. The causative agent in CSD appears to be multiple species and strains of Bartonella. Using polymerase chain reaction (PCR) techniques for amplification of highly variable regions of the 16S ribosomal RNA (rRNA) gene sequence, a very sensitive species- and strain-specific assay for CSD-causing Bartonella species was developed. PCR primers were designed to specifically amplify the 16S rRNA gene of Bartonella species but not of other microbial pathogens. This initial PCR was …

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The Impossibility Of Lujan's Project, Gene R. Nichol Jan 2001

The Impossibility Of Lujan's Project, Gene R. Nichol

Faculty Publications

No abstract provided.

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The Environmental Science Minor: A Disciplinary Approach To Interdisciplinary Studies With A Grounding In Undergraduate Research, Brian E. Bodenbender, Edward C. Hansen, Graham F. Peaslee, Jonathan W. Peterson Dec 2000

The Environmental Science Minor: A Disciplinary Approach To Interdisciplinary Studies With A Grounding In Undergraduate Research, Brian E. Bodenbender, Edward C. Hansen, Graham F. Peaslee, Jonathan W. Peterson

Faculty Publications

No abstract provided.

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Chromosome 17 Aneusomy Detected By Fluorescence In Situ Hybridization In Vulvar Squamous Cell Carcinomas And Synchronous Vulvar Skin, J. Andrew Carlson, Kara Healy, Tien Anh Tran, John Malfetano, Vincent L. Wilson, Angela Rohwedder, Jeffrey S. Ross Jan 2000

Chromosome 17 Aneusomy Detected By Fluorescence In Situ Hybridization In Vulvar Squamous Cell Carcinomas And Synchronous Vulvar Skin, J. Andrew Carlson, Kara Healy, Tien Anh Tran, John Malfetano, Vincent L. Wilson, Angela Rohwedder, Jeffrey S. Ross

Faculty Publications

Vulvar squamous cell carcinoma (SCC) affects a spectrum of women with granulomatous vulvar diseases, human papillomavirus (HPV) infections, and chronic inflammatory vulvar dermatoses. To determine whether there is evidence of chromosomal instability occurring in synchronous skin surrounding vulvar SCCs, we investigated abnormalities in chromosome 17 copy number. Samples of SCC, vulvar intraepithelial neoplasia (VIN), and surrounding vulvar skin were obtained from all vulvar excisions performed for squamous neoplasia at Albany Medical College from 1996 to 1997. Histological categorization, fluorescent in situ hybridization (FISH) for the α satellite region of chromosome 17, DNA content by image analysis, and Ki-67 labeling were …

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More Sorry Than Safe: Assessing The Precautionary Principle And The Proposed International Biosafety Protocol, Jonathan H. Adler Jan 2000

More Sorry Than Safe: Assessing The Precautionary Principle And The Proposed International Biosafety Protocol, Jonathan H. Adler

Faculty Publications

Part I of this paper provides a brief overview of the development of biotechnology, its regulation and its use, with a particular emphasis on agricultural biotechnology. Part II outlines the United Nations Convention on Biological Diversity, which provides an international legal framework for a biosafety protocol and summarizes the results of recent protocol negotiations, such as those conducted in Cartagena, Colombia in February 1999, which continued in Montreal in January 2000. Part III explains why the proposed protocol embodies a variant of the precautionary principle and why such policies may do more harm than good. This paper concludes with some …

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Ecological Legacies: Impacts On Ecosystems Of The Mcmurdo Dry Valleys, Daryl L. Moorhead, Peter T. Doran, Andrew G. Fountain, W. Berry Lyons, Diane M. Mcknight, John C. Priscu, Ross A. Virginia, Diana H. Wall Jan 1999

Ecological Legacies: Impacts On Ecosystems Of The Mcmurdo Dry Valleys, Daryl L. Moorhead, Peter T. Doran, Andrew G. Fountain, W. Berry Lyons, Diane M. Mcknight, John C. Priscu, Ross A. Virginia, Diana H. Wall

Faculty Publications

No abstract provided.

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Physical Controls On The Taylor Valley Ecosystem, Antarctica, Andrew G. Fountain, W. Berry Lyons, Melody B. Burkins, Gayle L. Dana, Peter T. Doran, Karen J. Lewis, Diane M. Mcknight, Daryl L. Moorhead, Andrew N. Parsons, John C. Priscu, Diana H. Wall, Robert A. Wharton, Ross A. Virginia Jan 1999

Physical Controls On The Taylor Valley Ecosystem, Antarctica, Andrew G. Fountain, W. Berry Lyons, Melody B. Burkins, Gayle L. Dana, Peter T. Doran, Karen J. Lewis, Diane M. Mcknight, Daryl L. Moorhead, Andrew N. Parsons, John C. Priscu, Diana H. Wall, Robert A. Wharton, Ross A. Virginia

Faculty Publications

No abstract provided.

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Seasonal Patterns And Controls On Net Ecosystem Co2 Exchange In A Boreal Peatland Complex, Jill L. Bubier, Patrick M. Crill, Tim R. Moore, Kathleen Savage, Ruth K. Varner Dec 1998

Seasonal Patterns And Controls On Net Ecosystem Co2 Exchange In A Boreal Peatland Complex, Jill L. Bubier, Patrick M. Crill, Tim R. Moore, Kathleen Savage, Ruth K. Varner

Faculty Publications

We measured seasonal patterns of net ecosystem exchange (NEE) of CO2 in a diverse peatland complex underlain by discontinuous permafrost in northern Manitoba, Canada, as part of the Boreal Ecosystems Atmosphere Study (BOREAS). Study sites spanned the full range of peatland trophic and moisture gradients found in boreal environments from bog (pH 3.9) to rich fen (pH 7.2). During midseason (July‐August, 1996), highest rates of NEE and respiration followed the trophic sequence of bog (5.4 to −3.9 μmol CO2 m−2 s−1) < poor fen (6.3 to −6.5 μmol CO2 m−2 s−1) < intermediate fen (10.5 to −7.8 μmol CO2 m−2 s−1) < rich fen (14.9 to −8.7 μmol CO2m−2 s−1). The sequence changed during spring (May‐June) and fall (September‐October) when ericaceous shrub (e.g., Chamaedaphne calyculata) bogs and sedge (Carex spp.) communities in poor to intermediate fens had higher maximum CO2 fixation rates than deciduous shrub‐dominated (Salix spp. and Betula spp.) rich fens. Timing of snowmelt and differential rates of peat surface thaw in microtopographic hummocks and hollows controlled the onset of carbon uptake in spring. Maximum photosynthesis and respiration were closely correlated throughout the growing season with a ratio of approximately 1/3 ecosystem respiration to maximum carbon uptake at all sites across the trophic gradient. Soil temperatures above the water table and timing of surface thaw and freeze‐up in the spring and fall were more important to net CO2 exchange than deep soil warming. This close coupling of maximum CO2 uptake and respiration to easily measurable variables, such as trophic status, peat temperature, and water table, will improve models of wetland carbon exchange. Although trophic status, aboveground net primary productivity, and surface temperatures were more important than water level in predicting respiration on a daily basis, the mean position of the water table was a good predictor (r2 = 0.63) of mean respiration rates across the range of plant community and moisture gradients. Q10 values ranged from 3.0 to 4.1 from bog to rich fen, but when normalized by above ground vascular plant biomass, the Q10 for all sites was 3.3.

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Effect Of Naturally Occurring Bromophenols On Sulfate Reduction And Ammonia Oxidation In Intertidal Sediments, C. Giray, G. M. King Sep 1997

Effect Of Naturally Occurring Bromophenols On Sulfate Reduction And Ammonia Oxidation In Intertidal Sediments, C. Giray, G. M. King

Faculty Publications

We examined the effect on ammonium oxidation and sulfate reduction of several brominated compounds [4-bromophenol, 2,4-dibromophenol (2,4-DBP), 2,6-dibromophenol and 2,4,6-tribromophenol] that occur naturally in enteropneusts. We compared rates of these processes with and without bromoorganics using bulk intertidal sediments and burrow wall sediments from 3 enteropneust species (2 containing 2,4-DBP and 1 containing 2,3,4-tribromopyrrole), a mollusc (Mya arenaria) and a polychaete (Nereis virens). Sulfate reduction in bulk sediment was unaffected by bromophenols at concentrations sediment, but was inhibited temporarily at 1 μmol cm-3. Sulfate reduction in burrow wall sediments differed from bulk sediments, but was not correlated with concentrations of …

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Country/Region Reports -- United States Of America, Linda A. Malone Jan 1996

Country/Region Reports -- United States Of America, Linda A. Malone

Faculty Publications

No abstract provided.

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