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Articles 1 - 23 of 23
Full-Text Articles in Marine Biology
Dataset: Ribbed Mussel Carbon And Nitrogen Composition Data, Robert Isdell, Ashley Rose, Donna Marie Bilkovic, Randolph Chambers
Dataset: Ribbed Mussel Carbon And Nitrogen Composition Data, Robert Isdell, Ashley Rose, Donna Marie Bilkovic, Randolph Chambers
Data
Ribbed mussel (Geukensia demissa) C:N ratios for tissue and shell samples are provided from a marsh in Virginia
Capturing Of Organic Carbon And Nitrogen In Eelgrass Sediments Of Southern Scandinavia, Carmen Leiva-Dueñas, Anna Elizabeth Løvgren Graversen, Gary T. Banta, Marianne Holmer, Pere Masque, Peter Anton Upadhyay Stæhr, Dorte Krause-Jensen
Capturing Of Organic Carbon And Nitrogen In Eelgrass Sediments Of Southern Scandinavia, Carmen Leiva-Dueñas, Anna Elizabeth Løvgren Graversen, Gary T. Banta, Marianne Holmer, Pere Masque, Peter Anton Upadhyay Stæhr, Dorte Krause-Jensen
Research outputs 2022 to 2026
The ability of seagrass meadows to filter nutrients and capture and store CO2 and nutrients in the form of organic carbon (OC) and nitrogen (N) in their sediments may help to mitigate local eutrophication as well as climate change via meadow restoration and protection. This study assesses OC and N sediment stocks (top 50 cm) and sequestration rates within Danish eelgrass meadows. At four locations, eelgrass-vegetated and nearby unvegetated plots were studied in protected and exposed areas. The average OC and N sediment 50 cm stocks were 2.6 ± 0.3 kg OC m − 2 and 0.23 ± 0.01 …
Levels Of Autotrophy And Heterotrophy In Mesophotic Corals Near The End Photic Zone, Amy Carmignani, Veronica Z. Radice, Kathryn M. Mcmahon, Alex I. Holman, Karen Miller, Kliti Grice, Zoe Richards
Levels Of Autotrophy And Heterotrophy In Mesophotic Corals Near The End Photic Zone, Amy Carmignani, Veronica Z. Radice, Kathryn M. Mcmahon, Alex I. Holman, Karen Miller, Kliti Grice, Zoe Richards
Biological Sciences Faculty Publications
Mesophotic corals live at ~30-150 m depth and can sustain metabolic processes under light-limited conditions by enhancing autotrophy through specialized photoadaptations or increasing heterotrophic nutrient acquisition. These acclimatory processes are often species-specific, however mesophotic ecosystems are largely unexplored and acclimation limits for most species are unknown. This study examined mesophotic coral ecosystems using a remotely operated vehicle (Ashmore Reef, Western Australia at 40–75m depth) to investigate the trophic ecology of five species of scleractinian coral (from genera Leptoseris, Pachyseris, and Craterastrea) using stable isotope analyses (δ13C and δ15N) of host and symbiont tissues …
Stable Isotopes Used To Infer Trophic Position Of Green Turtles (Chelonia Mydas) From Dry Tortugas National Park, Gulf Of Mexico, United States, David C. Roche, Michael S. Cherkiss, Brian J. Smith, Derek A. Burkholder, Kristen M. Hart
Stable Isotopes Used To Infer Trophic Position Of Green Turtles (Chelonia Mydas) From Dry Tortugas National Park, Gulf Of Mexico, United States, David C. Roche, Michael S. Cherkiss, Brian J. Smith, Derek A. Burkholder, Kristen M. Hart
Marine & Environmental Sciences Faculty Articles
Evaluating resource use patterns for imperiled species is critical for understanding what supports their populations. Here we established stable isotope (δ13C, δ15N) values for the endangered green sea turtle (Chelonia mydas) population found within the boundaries of Dry Tortugas National Park (DRTO), south Florida, USA. There is little gene flow between turtles sampled at DRTO and in other rookeries in Florida, underscoring the need to study this distinct population. Between 2008 and 2015 we collected multiple sample types (skin [homogenized epidermis/dermis], whole blood, red blood cells, plasma, carapace) from 151 unique green turtles, including …
Estimating The Denitrification Rate In Hood Canal Using Water Circulation, Spencer Johnson
Estimating The Denitrification Rate In Hood Canal Using Water Circulation, Spencer Johnson
WWU Honors College Senior Projects
Hood Canal is a long, fjordal estuarine inlet. Because of a sill near its mouth, Hood Canal experiences regular low oxygen in its bottom water; recently, dissolved oxygen has been even lower than usual, leading to fish kills and other ecosystem damage. Anthropogenic nutrients, particularly nitrogen, may be the cause, so it is important to quantify the components of the nitrogen cycle, like denitrification. To my knowledge, there is only one estimate of denitrification from Hood Canal in the literature. This study sought to supplement that data with an independent estimate of denitrification using water circulation along with N2 concentrations …
Size And Density Of Upside-Down Jellyfish, Cassiopea Sp., And Their Impact On Benthic Fluxes In A Caribbean Lagoon, Chester B. Zarnoch, Noshin Hossain, Erika Fusco, Mary Alldred, Timothy J. Hoellein, Sophia Perdikaris
Size And Density Of Upside-Down Jellyfish, Cassiopea Sp., And Their Impact On Benthic Fluxes In A Caribbean Lagoon, Chester B. Zarnoch, Noshin Hossain, Erika Fusco, Mary Alldred, Timothy J. Hoellein, Sophia Perdikaris
School of Global Integrative Studies: Faculty Publications
Anthropogenic disturbances may be increasing jellyfish populations globally. Epibenthic jellyfish are ideal organisms for studying this phenomenon due to their sessile lifestyle, broad geographic distribution, and prevalence in near-shore coastal environments. There are few studies, however, that have documented epibenthic jellyfish abundance and measured their impact on ecological processes in tropical ecosystems. In this study, the density and size of the upside-down jellyfish (Cassiopea spp.) were measured in Codrington Lagoon, Barbuda. A sediment core incubation study, with and without Cassiopea, also was performed to determine their impact on benthic oxygen and nutrient fluxes. Densities of Cassiopea were 24–168 …
Ammonium Recycling Supports Toxic Planktothrix Blooms In Sandusky Bay, Lake Erie: Evidence From Stable Isotope And Metatranscriptome Data, Justyna J. Hampel, Mark J. Mccarthy, Michelle Neudeck, George S. Bullerjahn, Robert Michael L. Mckay, Silvia E. Newell
Ammonium Recycling Supports Toxic Planktothrix Blooms In Sandusky Bay, Lake Erie: Evidence From Stable Isotope And Metatranscriptome Data, Justyna J. Hampel, Mark J. Mccarthy, Michelle Neudeck, George S. Bullerjahn, Robert Michael L. Mckay, Silvia E. Newell
Great Lakes Institute for Environmental Research Publications
Sandusky Bay, Lake Erie, receives high nutrient loadings (nitrogen and phosphorus) from the Sandusky River, which drains an agricultural watershed. Eutrophication and cyanobacterial harmful algal blooms (cyanoHABs) persist throughout summer. Planktothrix agardhii is the dominant bloom-forming species and the main producer of microcystins in Sandusky Bay. Non-N2 fixing cyanobacteria, such as Planktothrix and Microcystis, thrive on chemically reduced forms of nitrogen, such as ammonium (NH4+) and urea. Ammonium regeneration and potential uptake rates and total microbial community demand for NH4+ were quantified in Sandusky Bay. Potential NH4+ uptake rates in the light increased from June to August at all stations. …
A Multidecade Experiment Shows That Fertilization By Salmon Carcasses Enhanced Tree Growth In The Riparian Zone, Thomas P. Quinn, Helfield M. James, Catherine S. Austin, Rachel A. Hovel, Andrew Godard Bunn
A Multidecade Experiment Shows That Fertilization By Salmon Carcasses Enhanced Tree Growth In The Riparian Zone, Thomas P. Quinn, Helfield M. James, Catherine S. Austin, Rachel A. Hovel, Andrew Godard Bunn
Environmental Sciences Faculty and Staff Publications
As they return to spawn and die in their natal streams, anadromous, semelparous fishes such as Pacific salmon import marine‐derived nutrients to otherwise nutrient‐poor freshwater and riparian ecosystems. Diverse organisms exploit this resource, and previous studies have indicated that riparian tree growth may be enhanced by such marine‐derived nutrients. However, these studies were largely inferential and did not account for all factors affecting tree growth. As an experimental test of the contribution of carcasses to tree growth, for 20 yr, we systematically deposited all sockeye salmon (Oncorhynchus nerka) carcasses (217,055 individual salmon) in the riparian zone on one …
A Histological Assessment Of The Effects Of Elevated Temperature And Nitrogen On The Symbiodinium Of Palythoa Toxica (Walsh And Bowers 1971), Molly Westbrook
A Histological Assessment Of The Effects Of Elevated Temperature And Nitrogen On The Symbiodinium Of Palythoa Toxica (Walsh And Bowers 1971), Molly Westbrook
Honors College
Coral reefs around the world are suffering mass bleaching events caused by a combination of stressors, including rising ocean temperatures, acidity, pollution, increased suspended sediments, and increasing nitrogen levels. Corals harbor a complex microbial ecosystem consisting of bacteria, and algal symbionts known as Symbiodinium. This study examines the effects of elevated temperature, a known cause of bleaching, and elevated nitrogen, an increasingly important potential stressor for reefs, on the Symbiodinium of a zoanthid coral, Palythoa toxica. A total of 65 polyps were subjected to 5 different water treatments of 2 levels of elevated nitrogen, and 2 levels of …
Assessing Phytoplankton Nutritional Status And Potential Impact Of Wet Deposition In Seasonally Oligotrophic Waters Of The Mid-Atlantic Bight, P. N. Sedwick, P. W. Bernhardt, M. R. Mulholland, R. G. Najjar, L. M. Blumen, B. M. Sohst, C. Sookhdeo, Brittany Widner
Assessing Phytoplankton Nutritional Status And Potential Impact Of Wet Deposition In Seasonally Oligotrophic Waters Of The Mid-Atlantic Bight, P. N. Sedwick, P. W. Bernhardt, M. R. Mulholland, R. G. Najjar, L. M. Blumen, B. M. Sohst, C. Sookhdeo, Brittany Widner
OES Faculty Publications
To assess phytoplankton nutritional status in seasonally oligotrophic waters of the southern Mid-Atlantic Bight, and the potential for rain to stimulate primary production in this region during summer, shipboard bioassay experiments were performed using natural seawater and phytoplankton collected north and south of the Gulf Stream. Bioassay treatments comprised iron, nitrate, iron + nitrate, iron + nitrate + phosphate, and rainwater. Phytoplankton growth was inferred from changes in chlorophyll a, inorganic nitrogen, and carbon-13 uptake, relative to unamended control treatments. Results indicated the greatest growth stimulation by iron + nitrate + phosphate, intermediate growth stimulation by rainwater, modest growth …
Blooms Of Dinoflagellate Mixotrophs In A Lower Chesapeake Bay Tributary: Carbon And Nitrogen Uptake Over Diurnal, Seasonal, And Interannual Timescales, Margaret R. Mulholland, Ryan Morse, Todd Egerton, Peter W. Bernhardt, K. C. Filippino
Blooms Of Dinoflagellate Mixotrophs In A Lower Chesapeake Bay Tributary: Carbon And Nitrogen Uptake Over Diurnal, Seasonal, And Interannual Timescales, Margaret R. Mulholland, Ryan Morse, Todd Egerton, Peter W. Bernhardt, K. C. Filippino
OES Faculty Publications
A multi-year study was conducted in the eutrophic Lafayette River, a sub-tributary of the lower Chesapeake Bay during which uptake of inorganic and organic nitrogen (N) and C compounds was measured during multiple seasons and years when different dinoflagellate species were dominant. Seasonal dinoflagellate blooms included a variety of mixotrophic dinoflagellates including Heterocapsa triquetra in the late winter, Prorocentrum minimum in the spring, Akashiwo sanguinea in the early summer, and Scrippsiella trochoidea and Cochlodinium polykrikoides in late summer and fall. Results showed that no single N source fueled algal growth, rather rates of N and C uptake varied on seasonal …
Microorganisms Facilitate Uptake Of Dissolved Organic Nitrogen By Seagrass Leaves [Dataset], Flavia Tarquinio, Jeremy Bourgoure, Annette Koenders, Bonnie Laverock, Christin Säwström, Glenn A. Hyndes
Microorganisms Facilitate Uptake Of Dissolved Organic Nitrogen By Seagrass Leaves [Dataset], Flavia Tarquinio, Jeremy Bourgoure, Annette Koenders, Bonnie Laverock, Christin Säwström, Glenn A. Hyndes
Research Datasets
The database compiles data (used in Tarquinio et al. 2018, ISME Journal, accepted for publication) obtained from nitrogen stable isotope analysis (IRMS) and Nanoscale secondary ion mass spectrometry (NanoSIMS) of seagrass (Posidonia sinuosa) leaves and associated microorganisms. Row data (IRMS) are presented for bulk tissue 15N enrichment of P. sinuosa leaves at different times of incubation (plotted as bar chart in the manuscript), as well as the enrichment detected through the drawing of regions of interest (ROI) from NanoSIMS image analysis and plotted as box plots in the manuscript.
Differential Effects Of Bivalves On Sediment Nitrogen Cycling In A Shallow Coastal Bay, Ashley Smyth, Anna E. Murphy, Iris C. Anderson, Bk Song
Differential Effects Of Bivalves On Sediment Nitrogen Cycling In A Shallow Coastal Bay, Ashley Smyth, Anna E. Murphy, Iris C. Anderson, Bk Song
VIMS Articles
In coastal ecosystems, suspension-feeding bivalves can remove nitrogen though uptake and assimilation or enhanced denitrification. Bivalves may also retain nitrogen through increased mineralization and dissimilatory nitrate reduction to ammonium (DNRA). This study investigated the effects of oyster reefs and clam aquaculture on denitrification, DNRA, and nutrient fluxes (NOx, NH4 6 +, O2). Core incubations were conducted seasonally on sediments adjacent to restored oyster reefs (Crassostrea virginica), clam aquaculture beds (Mercenaria mercenaria) which contained live clams, and bare sediments from Smith Island Bay, Virginia, USA. Denitrification was significantly higher at oyster reef sediments and clam aquaculture site than bare sediment in …
The Growth Response Of Two Diatom Species To Atmospheric Dust From The Last Glacial Maximum, Tim M. Conway, Linn J. Hoffmann, Eike Breitbarth, Robert F. Strzepek, Eric W. Wolff
The Growth Response Of Two Diatom Species To Atmospheric Dust From The Last Glacial Maximum, Tim M. Conway, Linn J. Hoffmann, Eike Breitbarth, Robert F. Strzepek, Eric W. Wolff
Marine Science Faculty Publications
Relief of iron (Fe) limitation in the surface Southern Ocean has been suggested as one driver of the regular glacial-interglacial cycles in atmospheric carbon dioxide (CO2). The proposed cause is enhanced deposition of Fe-bearing atmospheric dust to the oceans during glacial intervals, with consequent effects on export production and the carbon cycle. However, understanding the role of enhanced atmospheric Fe supply in biogeochemical cycles is limited by knowledge of the fluxes and 'bioavailability' of atmospheric Fe during glacial intervals. Here, we assess the effect of Fe fertilization by dust, dry-extracted from the Last Glacial Maximum portion of the EPICA Dome …
The Individual And Interactive Effects Of Nitrogen And Phosphorus Enrichment On Coral Reefs, Andrew A. Shantz
The Individual And Interactive Effects Of Nitrogen And Phosphorus Enrichment On Coral Reefs, Andrew A. Shantz
FIU Electronic Theses and Dissertations
Human domination of global nutrient cycles is profoundly altering our planet. Yet on coral reefs, the effects of changing nutrient regimes have likely been over-simplified. This dissertation investigates the complexity of animal-nutrient interactions at the organismal level and explores how the outcomes of these interactions cascade through levels of biological organization. To do so, I examined the effects of nitrogen (N) and phosphorus (P) on corals and macroalgae, and how these effects in turn influenced reef communities and entire ecosystems. I show that P consistently increases coral growth rates while N has variable, often negative, effects on coral growth. The …
Global Solutions To Regional Problems: Collecting Global Expertise To Address The Problem Of Harmful Cyanobacterial Blooms. A Lake Erie Case Study, George S. Bullerjahn, Robert M. Mckay, Timothy W. Davis, David B. Baker, Gregory L. Boyer, Lesley V. D'Anglada, Gregory J. Doucette, Jeff C. Ho, Elena G. Irwin, Catherine L. Kling, Raphael M. Kudela, Rainer Kurmayer, Anna M. Michalak, Joseph D. Ortiz, Timothy G. Otten, Hans W. Paerl, Boqiang Qin, Brent L. Sohngen
Global Solutions To Regional Problems: Collecting Global Expertise To Address The Problem Of Harmful Cyanobacterial Blooms. A Lake Erie Case Study, George S. Bullerjahn, Robert M. Mckay, Timothy W. Davis, David B. Baker, Gregory L. Boyer, Lesley V. D'Anglada, Gregory J. Doucette, Jeff C. Ho, Elena G. Irwin, Catherine L. Kling, Raphael M. Kudela, Rainer Kurmayer, Anna M. Michalak, Joseph D. Ortiz, Timothy G. Otten, Hans W. Paerl, Boqiang Qin, Brent L. Sohngen
Great Lakes Institute for Environmental Research Publications
In early August 2014, the municipality of Toledo, OH (USA) issued a ‘do not drink’ advisory on their water supply directly affecting over 400,000 residential customers and hundreds of businesses (Wilson, 2014). This order was attributable to levels of microcystin, a potent liver toxin, which rose to 2.5 μg L−1 in finished drinking water. The Toledo crisis afforded an opportunity to bring together scientists from around the world to share ideas regarding factors that contribute to bloom formation and toxigenicity, bloom and toxin detection as well as prevention and remediation of bloom events. These discussions took place at an NSF- …
Patterns Of Transcript Abundance Of Eukaryotic Biogeochemically-Relevant Genes In The Amazon River Plume, Brian L. Zielinski, Andrew E. Allen, Edward J. Carpenter, Victoria J. Coles, Byron C. Crump, Mary Doherty, Rachel A. Foster, Joaquim I. Goes, Helga R. Gomes, Raleigh R. Hood, John P. Mccrow, Joseph P. Montoya, Ahmed Moustafa, Brandon M. Satinsky, Shalabh Sharma, Christa B. Smith, Patricia L. Yager, John H Paul
Patterns Of Transcript Abundance Of Eukaryotic Biogeochemically-Relevant Genes In The Amazon River Plume, Brian L. Zielinski, Andrew E. Allen, Edward J. Carpenter, Victoria J. Coles, Byron C. Crump, Mary Doherty, Rachel A. Foster, Joaquim I. Goes, Helga R. Gomes, Raleigh R. Hood, John P. Mccrow, Joseph P. Montoya, Ahmed Moustafa, Brandon M. Satinsky, Shalabh Sharma, Christa B. Smith, Patricia L. Yager, John H Paul
Marine Science Faculty Publications
The Amazon River has the largest discharge of all rivers on Earth, and its complex plume system fuels a wide array of biogeochemical processes, across a large area of the western tropical North Atlantic. The plume thus stimulates microbial processes affecting carbon sequestration and nutrient cycles at a global scale. Chromosomal gene expression patterns of the 2.0 to 156 μm size-fraction eukaryotic microbial community were investigated in the Amazon River Plume, generating a robust dataset (more than 100 million mRNA sequences) that depicts the metabolic capabilities and interactions among the eukaryotic microbes. Combining classical oceanographic field measurements with metatranscriptomics yielded …
Phytoplankton And Nutrient Dynamics In A Tidally Dominated Eutrophic Estuary: Daily Variability And Controls On Bloom Formation, Ryan E. Morse, Margaret R. Mulholland, Todd A. Egerton, Harold G. Marshall
Phytoplankton And Nutrient Dynamics In A Tidally Dominated Eutrophic Estuary: Daily Variability And Controls On Bloom Formation, Ryan E. Morse, Margaret R. Mulholland, Todd A. Egerton, Harold G. Marshall
OES Faculty Publications
To better understand nutrient dynamics and factors that promote the initiation of algal blooms, the Lafayette River, a tidal subestuary of Chesapeake Bay that experiences seasonal algal blooms, was sampled daily for a period of 54 d in the fall of 2005. Three phytoplankton blooms (chl a concentrations exceeding twice the average of monthly measurements from 2000 to 2009) occurred during this period: a mixed bloom of Akashiwo sanguinea and Gymnodinium sp., a monospecific Skeletonema costatum bloom, and a monospecific Gymnodinium sp. bloom. Over the sampling period, nutrient concentrations increased following precipitation events and were elevated between bloom periods but …
Fertilizer And Stormwater Runoff Outreach Program In Newcastle, Nh, David Anderson
Fertilizer And Stormwater Runoff Outreach Program In Newcastle, Nh, David Anderson
PREP Reports & Publications
The New Hampshire Coastal Protection Partnership (NH Coast) implemented a year long pilot public education and outreach program in the Town of New Castle aimed at reducing nitrogen pollution from lawn fertilizers and promoting rain gardens as a solution to storm water runoff and nonpoint source pollution. A total of 77 landowners representing 138 acres of land pledged to either not use lawn fertilizers or use only low phosphorus, slow release nitrogen brands. The program also resulted in the installation of New Castle’s first demonstration rain garden.
Ecological And Physiological Controls Of Species Composition In Green Macroalgal Blooms, Kathryn L. Van Alstyne Dr., Timothy A. Nelson, Karalon Haberlin, Amorah V. Nelson, Heather Ribarich, Ruth Hotchkiss, Lee Buckingham, Dejah J. Simunds, Kerri Fredrickson
Ecological And Physiological Controls Of Species Composition In Green Macroalgal Blooms, Kathryn L. Van Alstyne Dr., Timothy A. Nelson, Karalon Haberlin, Amorah V. Nelson, Heather Ribarich, Ruth Hotchkiss, Lee Buckingham, Dejah J. Simunds, Kerri Fredrickson
Shannon Point Marine Center Faculty Publications
Green macroalgal blooms have substantially altered marine community structure and function, specifically by smothering seagrasses and other primary producers that are critical to commercial fisheries and by creating anoxic conditions in enclosed embayments. Bottom-up factors are viewed as the primary drivers of these blooms, but increasing attention has been paid to biotic controls of species composition. In Washington State, USA, blooms are often dominated by Ulva spp. intertidally and Ulvaria obscura subtidally. Factors that could cause this spatial difference were examined, including competition, grazer preferences, salinity, photoacclimation, nutrient requirements, and responses to nutrient enrichment. Ova specimens grew faster than …
Interactions Between Changing Pco2, N2 Fixation, And Fe Limitation In The Marine Unicellular Cyanobacterium Crocosphaera, Fei-Xue Fu, Margaret R. Mulholland, Nathan S. Garcia, Aaron Beck, Mark E. Warner, Sergio A. Sañudo, David A. Hutchins
Interactions Between Changing Pco2, N2 Fixation, And Fe Limitation In The Marine Unicellular Cyanobacterium Crocosphaera, Fei-Xue Fu, Margaret R. Mulholland, Nathan S. Garcia, Aaron Beck, Mark E. Warner, Sergio A. Sañudo, David A. Hutchins
OES Faculty Publications
We examined the physiological responses of steady-state iron (Fe)-replete and Fe-limited cultures of the biogeochemically critical marine unicellular diazotrophic cyanobacterium Crocosphaera at glacial (19 Pa; 190 ppm), current (39 Pa; 380 ppm), and projected year 2100 (76 Pa; 750 ppm) CO2 levels. Rates of N2 and CO2 fixation and growth increased in step with increasing partial pressure of CO2 (pCO2), but only under Fe- replete conditions. N2) and carbon fixation rates at 75 Pa CO2 were 1.4-1.8-fold and 1.2-2.0-fold higher, respectively, relative to those at present day and glacial pCO2 …
Biochemical Composition Of Particles And Dissolved Organic Matter Slong An Estuarine Gradient: Sources And Implications For Dom Reactivity, Antonio Mannino, H. Rodger Harvey
Biochemical Composition Of Particles And Dissolved Organic Matter Slong An Estuarine Gradient: Sources And Implications For Dom Reactivity, Antonio Mannino, H. Rodger Harvey
OES Faculty Publications
The chemical composition of high molecular weight dissolved organic matter (DOM) and particulate organic matter (POM) was examined along the salinity gradient of the Delaware Estuary. DOM was collected and fractionated by tangential-flow ultrafiltration into 1-30 kDa (HDOM; high molecular weight) and 30 kDa to 0.2 μm (VHDOM; very high molecular weight) and compared to particles collected in parallel. Polysaccharides comprised 12-43% of particulate organic carbon (POC), 30-56% of VHDOM carbon, and 7.5-19% of HDOM carbon. Hydrolyzable amino acids comprised 17-38% of POC, 5.4-12% of VHDOM carbon, and 1.5-4.2% of HDOM carbon. Only 7-43% of dissolved organic nitrogen in VHDOM …
Organic Carbon, Hydrogen, And Nitrogen Concentrations In Surficial Sediments From Western Long Island Sound, Connecticut And New York, Roman Zajac, Larry J. Poppe, Ralph S. Lewis, S E. Pratt, Zofia J. Mlodzinska, B. B. Taylor, Mary L. Digiacomo-Cohen
Organic Carbon, Hydrogen, And Nitrogen Concentrations In Surficial Sediments From Western Long Island Sound, Connecticut And New York, Roman Zajac, Larry J. Poppe, Ralph S. Lewis, S E. Pratt, Zofia J. Mlodzinska, B. B. Taylor, Mary L. Digiacomo-Cohen
Biology and Environmental Science Faculty Publications
Total organic carbon, hydrogen, and nitrogen (CHN) analyses were performed on 147 surficial sediment samples from study areas off the Norwalk Islands and Milford, Connecticut, in western Long Island Sound. The CHN data and gross lithologic descriptions of the sediments are reported herein. The concentrations of total organic carbon (TOC), hydrogen, and nitrogen in these samples average 1.54, 1.40, and 0.17 weight percent, respectively. The individual CHN concentrations vary inversely with grain size, with CHN values increasing with the percent fines. Increasing nutrient inputs and decreasing circulation cause TOC and nitrogen values to generally increase westward within the Sound. C/N …