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- Phytoplankton (7)
- Bacteria (5)
- Carbon dioxide (4)
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- Copepod (3)
- Cyanobacteria (3)
- Diatom (3)
- Eelgrass (3)
- Iron (3)
- Irradiance (3)
- Nitrogen (3)
- Phosphorus (3)
- Photosynthesis (3)
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- Seagrass (3)
- Zostera marina (3)
- Aquatic pathogens (2)
- Atlantic Ocean (2)
- Attached bacteria (2)
- CO2 (2)
- Carbon (2)
- Chlorophyll (2)
- Enzymes (2)
- Estuary (2)
- Eukaryotic microbes (2)
- Euphotic zone (2)
- Extracellular enzymes (2)
- Fatty acids (2)
- Feeding (2)
Articles 1 - 30 of 65
Full-Text Articles in Physical Sciences and Mathematics
A Comparison Of Adenosine Triphosphate With Other Metrics Of Microbial Biomass In A Gradient From The North Atlantic To The Chesapeake Bay, Alexander B. Bochdansky, Amber A. Beecher, Joshua R. Calderon, Alison N. Stouffer, Nyjaee N. Washington
A Comparison Of Adenosine Triphosphate With Other Metrics Of Microbial Biomass In A Gradient From The North Atlantic To The Chesapeake Bay, Alexander B. Bochdansky, Amber A. Beecher, Joshua R. Calderon, Alison N. Stouffer, Nyjaee N. Washington
OES Faculty Publications
A new, simplified protocol for determining particulate adenosine triphosphate (ATP) levels allows for the assessment of microbial biomass distribution in aquatic systems at a high temporal and spatial resolution. A comparison of ATP data with related variables, such as particulate carbon, nitrogen, chlorophyll, and turbidity in pelagic samples, yielded significant and strong correlations in a gradient from the tributaries of the Chesapeake Bay (sigma-t = 8) to the open North Atlantic (sigma-t = 29). Correlations varied between ATP and biomass depending on the microscopic method employed. Despite the much greater effort involved, biomass determined by microscopy correlated poorly with other …
Atmospheric Input And Seasonal Inventory Of Dissolved Iron In The Sargasso Sea: Implications For Iron Dynamics In Surface Waters Of The Subtropical Ocean, Peter N. Sedwick, Bettina M. Sohst, K. N. Buck, S. Caprara, R. J. Johnson, D. C. Ohnemus, L. E. Sofen, A. Tagliabue, B. S. Twining, Tara E. Williams
Atmospheric Input And Seasonal Inventory Of Dissolved Iron In The Sargasso Sea: Implications For Iron Dynamics In Surface Waters Of The Subtropical Ocean, Peter N. Sedwick, Bettina M. Sohst, K. N. Buck, S. Caprara, R. J. Johnson, D. C. Ohnemus, L. E. Sofen, A. Tagliabue, B. S. Twining, Tara E. Williams
OES Faculty Publications
Constraining the role of dust deposition in regulating the concentration of the essential micronutrient iron in surface ocean waters requires knowledge of the flux of seawater-soluble iron in aerosols and the replacement time of dissolved iron (DFe) in the euphotic zone. Here we estimate these quantities using seasonally resolved DFe data from the Bermuda Atlantic Time-series Study region and weekly-scale measurements of iron in aerosols and rain from Bermuda during 2019. In response to seasonal changes in vertical mixing, primary production and dust deposition, surface DFe concentrations vary from ∼0.2 nM in early spring to >1 nM in late summer, …
The Vulnerability And Resilience Of Seagrass Ecosystems To Marine Heatwaves In New Zealand: A Remote Sensing Analysis Of Seascape Metrics Using Planetscope Imagery, Ken Joseph E. Clemente, Mads S. Thomsen, Richard C. Zimmerman
The Vulnerability And Resilience Of Seagrass Ecosystems To Marine Heatwaves In New Zealand: A Remote Sensing Analysis Of Seascape Metrics Using Planetscope Imagery, Ken Joseph E. Clemente, Mads S. Thomsen, Richard C. Zimmerman
OES Faculty Publications
Seagrasses are foundation species that provide ecosystem functions and services, including increased biodiversity, sediment retention, carbon sequestration, and fish nursery habitat. However, anthropogenic stressors that reduce water quality, impose large-scale climate changes, and amplify weather patterns, such as marine heatwaves, are altering seagrass meadow configurations. Quantifying large-scale trends in seagrass distributions will help evaluate the impacts of climate drivers on their functions and services. Here, we quantified spatiotemporal dynamics in abundances and configurations of intertidal and shallow subtidal seagrass (Zostera muelleri) meadows in 20 New Zealand (NZ) estuaries that span a 5-year period (mid/late 2016–early 2022) just before, …
The Importance Of Winter Dinoflagellate Blooms In Chesapeake Bay— A Missing Link In Bay Productivity, Nicole C. Millette, Sophie Clayton, Margaret R. Mulholland, Leah Gibala-Smith, Michael Lane
The Importance Of Winter Dinoflagellate Blooms In Chesapeake Bay— A Missing Link In Bay Productivity, Nicole C. Millette, Sophie Clayton, Margaret R. Mulholland, Leah Gibala-Smith, Michael Lane
OES Faculty Publications
It is widely assumed that phytoplankton abundance and productivity decline during temperate winters because of low irradiance and temperatures. However, winter phytoplankton blooms commonly occur in temperate estuaries, but they are often undocumented because of reduced water quality monitoring in winter. The small body of in situ work that has been done on winter blooms suggests they can be of enormous consequence to ecosystems. However, because monitoring is often reduced or stopped altogether during winter, it is unclear how widespread these blooms are or how long they can last. We analyzed an over 30-year record of monthly phytoplankton monitoring samples …
A Global Comparison Of Marine Chlorophyll Variability Observed In Eulerian And Lagrangian Perspectives, Angela M. Kuhn, Matthew Mazloff, Stephanie Dutkiewicz, Oliver Jahn, Sophie Clayton, Tatiana Rynearson, Andrew D. Barton
A Global Comparison Of Marine Chlorophyll Variability Observed In Eulerian And Lagrangian Perspectives, Angela M. Kuhn, Matthew Mazloff, Stephanie Dutkiewicz, Oliver Jahn, Sophie Clayton, Tatiana Rynearson, Andrew D. Barton
OES Faculty Publications
The California Current System is a diatom‐dominated region characterized by seasonal coastal upwelling and additional elevated mesoscale activity. Cyclonic mesoscale eddies in the region trap productive coastal waters with their planktonic communities and transport them offshore with limited interaction with surrounding waters, effectively acting as natural mesocosms, where phytoplankton populations undergo ecological succession as eddies age. This study examines diatom community composition within two mesoscale cyclonic eddies that formed in the same region of the California Current System 2 months apart and in the California Current waters surrounding them. The diatom communities were analyzed in the context of shifting environmental …
A Subsurface Eddy Associated With A Submarine Canyon Increases Availability And Delivery Of Simulated Antarctic Krill To Penguin Foraging Regions, K. Hudson, M. J. Oliver, J. Kohut, Michael S. Dinniman, John M. Klinck, M. A. Cimino, K. S. Bernard, H. Statscewich, W. Fraser
A Subsurface Eddy Associated With A Submarine Canyon Increases Availability And Delivery Of Simulated Antarctic Krill To Penguin Foraging Regions, K. Hudson, M. J. Oliver, J. Kohut, Michael S. Dinniman, John M. Klinck, M. A. Cimino, K. S. Bernard, H. Statscewich, W. Fraser
OES Faculty Publications
The distribution of marine zooplankton depends on both ocean currents and swimming behavior. Many zooplankton perform diel vertical migration (DVM) between the surface and subsurface, which can have different current regimes. If concentration mechanisms, such as fronts or eddies, are present in the subsurface, they may impact zooplankton near-surface distributions when they migrate to near-surface waters. A subsurface, retentive eddy within Palmer Deep Canyon (PDC), a submarine canyon along the West Antarctic Peninsula (WAP), retains diurnal vertically migrating zooplankton in previous model simulations. Here, we tested the hypothesis that the presence of the PDC and its associated subsurface eddy increases …
Temporal Stability Of Seagrass Extent, Leaf Area, And Carbon Storage In St. Joseph Bay, Florida: A Semi-Automated Remote Sensing Analysis, Marie Cindy Lebrasse, Blake A. Schaeffer, Megan M. Coffer, Peter J. Whitman, Richard C. Zimmerman, Victoria J. Hill, Kazi A. Islam, Jiang Li, Christopher L. Osburn
Temporal Stability Of Seagrass Extent, Leaf Area, And Carbon Storage In St. Joseph Bay, Florida: A Semi-Automated Remote Sensing Analysis, Marie Cindy Lebrasse, Blake A. Schaeffer, Megan M. Coffer, Peter J. Whitman, Richard C. Zimmerman, Victoria J. Hill, Kazi A. Islam, Jiang Li, Christopher L. Osburn
OES Faculty Publications
Seagrasses are globally recognized for their contribution to blue carbon sequestration. However, accurate quantification of their carbon storage capacity remains uncertain due, in part, to an incomplete inventory of global seagrass extent and assessment of its temporal variability. Furthermore, seagrasses are undergoing significant decline globally, which highlights the urgent need to develop change detection techniques applicable to both the scale of loss and the spatial complexity of coastal environments. This study applied a deep learning algorithm to a 30-year time series of Landsat 5 through 8 imagery to quantify seagrass extent, leaf area index (LAI), and belowground organic carbon (BGC) …
Editorial: Advances In Understanding Lateral Blue Carbon Export From Coastal Ecosystems, Kai Xiao, Nengwang Chen, Zhaohui Aleck Wang, Joseph James Tamborski, Damien Troy Maher, Xuan Yu
Editorial: Advances In Understanding Lateral Blue Carbon Export From Coastal Ecosystems, Kai Xiao, Nengwang Chen, Zhaohui Aleck Wang, Joseph James Tamborski, Damien Troy Maher, Xuan Yu
OES Faculty Publications
No abstract provided.
Bio-Go-Ship: The Time Is Right To Establish Global Repeat Sections Of Ocean Biology, Sophie Clayton, Harriet Alexander, Jason R. Graff, Nicole J. Poulton, Luke R. Thompson, Heather Benway, Emmanuel Boss, Adam Martiny
Bio-Go-Ship: The Time Is Right To Establish Global Repeat Sections Of Ocean Biology, Sophie Clayton, Harriet Alexander, Jason R. Graff, Nicole J. Poulton, Luke R. Thompson, Heather Benway, Emmanuel Boss, Adam Martiny
OES Faculty Publications
In this article, we present Bio-GO-SHIP, a new ocean observing program that will incorporate sustained and consistent global biological ocean observations into the Global Ocean Ship-based Hydrographic Investigations Program (GO-SHIP). The goal of Bio-GO-SHIP is to produce systematic and consistent biological observations during global ocean repeat hydrographic surveys, with a particular focus on the planktonic ecosystem. Ocean plankton are an essential component of the earth climate system, form the base of the oceanic food web and thereby play an important role in influencing food security and contributing to the Blue Economy. Despite its importance, ocean biology is largely under-sampled in …
Lipid Markers And Compound-Specific Carbon Isotopes As Diet And Biosynthesis Reflectors In The Northern Neptune Whelk Neptunea Heros, H. Rodger Harvey, Rachel Mcmahon, Karen A. Taylor
Lipid Markers And Compound-Specific Carbon Isotopes As Diet And Biosynthesis Reflectors In The Northern Neptune Whelk Neptunea Heros, H. Rodger Harvey, Rachel Mcmahon, Karen A. Taylor
OES Faculty Publications
A suite of lipid biomarkers plus compound-specific carbon isotopes of major sterols were determined in muscle tissues across increasing sizes of northern Neptune whelks Neptunea heros, developing eggs and potential diets to link trophic patterns, metabolism and carbon sources on the Chukchi Sea shelf. Analysis of primary prey included the northern clam Astarte borealis, water column particulate organic matter (POM) and surface sediments near the collection sites. Sterols specific to major algal groups along with algal-derived polyunsaturated fatty acids (C20:5n-3, C20:4n-3, C22:6n-3) in whelk muscle tissue reflected the importance of algal primary production to benthic consumers and its …
A Kernel-Based Change Detection Method To Map Shifts In Phytoplankton Communities Measured By Flow Cytometry, Corinne Jones, Sophie Clayton, François Ribalet, E. Virginia Armbrust, Zaid Harchaoui
A Kernel-Based Change Detection Method To Map Shifts In Phytoplankton Communities Measured By Flow Cytometry, Corinne Jones, Sophie Clayton, François Ribalet, E. Virginia Armbrust, Zaid Harchaoui
OES Faculty Publications
1. Automated, ship-board flow cytometers provide high-resolution maps of phytoplankton composition over large swaths of the world's oceans. They therefore pave the way for understanding how environmental conditions shape community structure. Identification of community changes along a cruise transect commonly segments the data into distinct regions. However, existing segmentation methods are generally not applicable to flow cytometry data, as these data are recorded as ‘point cloud’ data, with hundreds or thousands of particles measured during each time interval. Moreover, nonparametric segmentation methods that do not rely on prior knowledge of the number of species are desirable to map community shifts. …
Marine Phytoplankton Functional Types Exhibit Diverse Responses To Thermal Change, S. I. Anderson, A. D. Barton, Sophie Clayton, S. Dutkiewicz, T. A. Rynearson
Marine Phytoplankton Functional Types Exhibit Diverse Responses To Thermal Change, S. I. Anderson, A. D. Barton, Sophie Clayton, S. Dutkiewicz, T. A. Rynearson
OES Faculty Publications
Marine phytoplankton generate half of global primary production, making them essential to ecosystem functioning and biogeochemical cycling. Though phytoplankton are phylogenetically diverse, studies rarely designate unique thermal traits to different taxa, resulting in coarse representations of phytoplankton thermal responses. Here we assessed phytoplankton functional responses to temperature using empirically derived thermal growth rates from four principal contributors to marine productivity: diatoms, dinoflagellates, cyanobacteria, and coccolithophores. Using modeled sea surface temperatures for 1950-1970 and 2080-2100, we explored potential alterations to each group's growth rates and geographical distribution under a future climate change scenario. Contrary to the commonly applied Eppley formulation, our …
Potential Virus-Mediated Nitrogen Cycling In Oxygen-Depleted Oceanic Waters, M. Consuelo Gazitúa, Dean R. Vik, Simon Roux, Ann C. Gregory, Benjamin Bolduc, Brittany Widner, Margaret R. Mulholland, Steven J. Hallam, Osvaldo Ulloa, Matthew B. Sullivan
Potential Virus-Mediated Nitrogen Cycling In Oxygen-Depleted Oceanic Waters, M. Consuelo Gazitúa, Dean R. Vik, Simon Roux, Ann C. Gregory, Benjamin Bolduc, Brittany Widner, Margaret R. Mulholland, Steven J. Hallam, Osvaldo Ulloa, Matthew B. Sullivan
OES Faculty Publications
Viruses play an important role in the ecology and biogeochemistry of marine ecosystems. Beyond mortality and gene transfer, viruses can reprogram microbial metabolism during infection by expressing auxiliary metabolic genes (AMGs) involved in photosynthesis, central carbon metabolism, and nutrient cycling. While previous studies have focused on AMG diversity in the sunlit and dark ocean, less is known about the role of viruses in shaping metabolic networks along redox gradients associated with marine oxygen minimum zones (OMZs). Here, we analyzed relatively quantitative viral metagenomic datasets that profiled the oxygen gradient across Eastern Tropical South Pacific (ETSP) OMZ waters, assessing whether OMZ …
Closing The Oxygen Mass Balance In Shallow Coastal Ecosystems, Matthew H. Long, Jennie E. Rheuban, Daniel C. Mccorkle, David J. Burdige, Richard C. Zimmerman
Closing The Oxygen Mass Balance In Shallow Coastal Ecosystems, Matthew H. Long, Jennie E. Rheuban, Daniel C. Mccorkle, David J. Burdige, Richard C. Zimmerman
OES Faculty Publications
The oxygen concentration in marine ecosystems is influenced by production and consumption in the water column and fluxes across both the atmosphere-water and benthic-water boundaries. Each of these fluxes has the potential to be significant in shallow ecosystems due to high fluxes and low water volumes. This study evaluated the contributions of these three fluxes to the oxygen budget in two contrasting ecosystems, a Zostera marina (eelgrass) meadow in Virginia, U.S.A., and a coral reef in Bermuda. Benthic oxygen fluxes were evaluated by eddy covariance. Water column oxygen production and consumption were measured using an automated water incubation system. Atmosphere-water …
Patterns Of Diatom Diversity Correlate With Dissolved Trace Metal Concentrations And Longitudinal Position In The Notheast Pacific Coastal Offshore Transition Zone, P. Dreux Chappell, E. Virginia Armbrust, Katherine A. Barbeau, Randelle M. Bundy, Jagruti Vedamati, Bethany D. Jenkins
Patterns Of Diatom Diversity Correlate With Dissolved Trace Metal Concentrations And Longitudinal Position In The Notheast Pacific Coastal Offshore Transition Zone, P. Dreux Chappell, E. Virginia Armbrust, Katherine A. Barbeau, Randelle M. Bundy, Jagruti Vedamati, Bethany D. Jenkins
OES Faculty Publications
Diatoms are important primary producers in the northeast Pacific Ocean, with their productivity closely linked to pulses of trace elements in the western high nitrate, low chlorophyll (HNLC) region of the oceanographic time series transect 'Line P.' Recently, the coastal-HNLC transition zone of the Line P transect was identified as a hotspot of phytoplankton productivity, potentially controlled by a combination of trace element and macronutrient concentrations. Here we describe diatom community composition in the eastern Line P transect, including the coastal- HNLC transition zone, with a method using high-throughput sequencing of diatom 18S gene amplicons. We identified significant correlations between …
Spatial Structuring And Life History Connectivity Of Antarctic Silverfish Along The Southern Continental Shelf Of The Weddell Sea, Jilda Alicia Caccavo, Julian R. Ashford, Svenja Ryan, Chiara Papetti, Michael Schröder, Lorenzo Zane
Spatial Structuring And Life History Connectivity Of Antarctic Silverfish Along The Southern Continental Shelf Of The Weddell Sea, Jilda Alicia Caccavo, Julian R. Ashford, Svenja Ryan, Chiara Papetti, Michael Schröder, Lorenzo Zane
OES Faculty Publications
A multi-disciplinary approach was employed to examine a physical-biological population hypothesis for a critical forage species, the Antarctic silverfish Pleuragramma antarctica. Caccavo et al. (2018; Sci Rep 8:17856) had shown strong gene flow along the westward Antarctic Slope Current, in addition to spatially recurring length modes that provided evidence for episodic connectivity. In this paper, otolith nucleus chemistry from a subset of fish collected in the southern Weddell Sea as part of a hydrographic survey of the Filchner Trough system was used to test between connectivity scenarios. Nucleus chemistry, which reflects environmental exposure during early life, showed significant …
Along-Shelf Connectivity And Circumpolar Gene Flow In Antarctic Silverfish (Pleuragramma Antarctica), Jilda Alicia Caccavo, Chiara Papetti, Maj Wetjen, Rainer Knust, Julian R. Ashford, Lorenzo Zane
Along-Shelf Connectivity And Circumpolar Gene Flow In Antarctic Silverfish (Pleuragramma Antarctica), Jilda Alicia Caccavo, Chiara Papetti, Maj Wetjen, Rainer Knust, Julian R. Ashford, Lorenzo Zane
OES Faculty Publications
The Antarctic silverfish (Pleuragramma antarctica) is a critically important forage species with a circumpolar distribution and is unique among other notothenioid species for its wholly pelagic life cycle. Previous studies have provided mixed evidence of population structure over regional and circumpolar scales. The aim of the present study was to test the recent population hypothesis for Antarctic silverfish, which emphasizes the interplay between life history and hydrography in shaping connectivity. A total of 1067 individuals were collected over 25 years from different locations on a circumpolar scale. Samples were genotyped at fifteen microsatellites to assess population differentiation and …
Experimental Impacts Of Climate Warming And Ocean Carbonation On Eelgrass Zostera Marina, Richard C. Zimmerman, Victoria J. Hill, Malee Jinuntuya, Billur Celebi, David Ruble, Miranda Smith, Tiffany Cedeno, W. Mark Swingle
Experimental Impacts Of Climate Warming And Ocean Carbonation On Eelgrass Zostera Marina, Richard C. Zimmerman, Victoria J. Hill, Malee Jinuntuya, Billur Celebi, David Ruble, Miranda Smith, Tiffany Cedeno, W. Mark Swingle
OES Faculty Publications
CO2 is a critical and potentially limiting substrate for photosynthesis of both terrestrial and aquatic ecosystems. In addition to being a climate-warming greenhouse gas, increasing concentrations of CO2 will dissolve in the oceans, eliciting both negative and positive responses among organisms in a process commonly known as ocean acidification. The dissolution of CO2 into ocean surface waters, however, also increases its availability for photosynthesis, to which the highly successful, and ecologically important, seagrasses respond positively. Thus, the process might be more accurately characterized as ocean carbonation. This experiment demonstrated that CO2 stimulation of primary production enhances …
Multiple Mating By Females In The Chesapeake Bay Blue Crab Callinectes Sapidus Population, S. Wells, J. Mcconaugha, L. Horth
Multiple Mating By Females In The Chesapeake Bay Blue Crab Callinectes Sapidus Population, S. Wells, J. Mcconaugha, L. Horth
OES Faculty Publications
Mature females of the Chesapeake Bay (USA) blue crab Callinectes sapidus population mate multiple times. Microsatellite DNA analysis of sperm stored in the spermathecae has shown that virtually all (~97%, 104 out of 107) females collected in a 2009−2010 study mated with at least 2 males. Enumeration of stored sperm revealed that despite multiple mating, some females did not have enough sperm to fulfill their lifetime reproductive potential, suggesting that female blue crabs may experience varying levels of sperm limitation. This could result from multiple factors. The average body size of males in the population has decreased, which reduces the …
Eukaryotic Microbes, Principally Fungi And Labyrinthulomycetes, Dominate Biomass On Bathypelagic Marine Snow, Alexander B. Bochdansky, Melissa A. Clouse, Gerhard J. Herndl
Eukaryotic Microbes, Principally Fungi And Labyrinthulomycetes, Dominate Biomass On Bathypelagic Marine Snow, Alexander B. Bochdansky, Melissa A. Clouse, Gerhard J. Herndl
OES Faculty Publications
In the bathypelagic realm of the ocean, the role of marine snow as a carbon and energy source for the deep-sea biota and as a potential hotspot of microbial diversity and activity has not received adequate attention. Here, we collected bathypelagic marine snow by gentle gravity filtration of sea water onto μm filters from similar to 1000 to 3900 m to investigate the relative distribution of eukaryotic microbes. Compared with sediment traps that select for fast-sinking particles, this method collects particles unbiased by settling velocity. While prokaryotes numerically exceeded eukaryotes on marine snow, eukaryotic microbes belonging to two very distant …
A Highly Sensitive Underwater Video System For Use In Turbid Aquaculture Ponds, Chin-Chang Hung, Shih-Chieh Tsao, Kuo-Hao Huang, Hsu-Kunag Chang, Fred C. Dobbs
A Highly Sensitive Underwater Video System For Use In Turbid Aquaculture Ponds, Chin-Chang Hung, Shih-Chieh Tsao, Kuo-Hao Huang, Hsu-Kunag Chang, Fred C. Dobbs
OES Faculty Publications
The turbid, low-light waters characteristic of aquaculture ponds have made it difficult or impossible for previous video cameras to provide clear imagery of the ponds' benthic habitat. We developed a highly sensitive, underwater video system (UVS) for this particular application and tested it in shrimp ponds having turbidities typical of those in southern Taiwan. The system's high-quality video stream and images, together with its camera capacity (up to nine cameras), permit in situ observations of shrimp feeding behavior, shrimp size and internal anatomy, and organic matter residues on pond sediments. The UVS can operate continuously and be focused remotely, a …
The Contribution Of Marine Aggregate-Associated Bacteria To The Accumulation Of Pathogenic Bacteria In Oysters: An Agent-Based Model, Andrew M. Kramer, J. Evan Ward, Fred C. Dobbs, Melissa L. Pierce
The Contribution Of Marine Aggregate-Associated Bacteria To The Accumulation Of Pathogenic Bacteria In Oysters: An Agent-Based Model, Andrew M. Kramer, J. Evan Ward, Fred C. Dobbs, Melissa L. Pierce
OES Faculty Publications
Bivalves process large volumes of water, leading to their accumulation of bacteria, including potential human pathogens (e.g., vibrios). These bacteria are captured at low efficiencies when freely suspended in the water column, but they also attach to marine aggregates, which are captured with near 100% efficiency. For this reason, and because they are often enriched with heterotrophic bacteria, marine aggregates have been hypothesized to function as important transporters of bacteria into bivalves. The relative contribution of aggregates and unattached bacteria to the accumulation of these cells, however, is unknown. We developed an agent-based model to simulate accumulation of vibrio-type bacteria …
Effects Of Temperature, Irradiance And Pco2 On The Growth And Nitrogen Utilization Of Prorocentrum Donghaiense, Zhangxi Hu, Margaret R. Mulholland, Ning Xu, Shunshan Duan
Effects Of Temperature, Irradiance And Pco2 On The Growth And Nitrogen Utilization Of Prorocentrum Donghaiense, Zhangxi Hu, Margaret R. Mulholland, Ning Xu, Shunshan Duan
OES Faculty Publications
Environmental factors such as temp erature, irradiance, and nitrogen (N) supply affect the growth of Prorocentrum donghaiense, but the interactive effects of these physical factors and the effects of atmospheric CO2 (pCO2) on growth and N uptake have not been examined. We compared growth kinetics of P. donghaiense grown on 4 different N substrates (nitrate [NO3 -], ammonium [NH4 +], urea, and glutamic acid [glu]) with respect to temperature, irradiance, and pCO2. Temperature (15 to 30°C) had a positive effect on growth (max. growth rates: 0.17 to 0.65 d …
Iron Deficiency Increases Growth And Nitrogen-Fixation Rates Of Phosphorus-Deficient Marine Cyanobacteria, Nathan S. Garcia, Feixue Fu, Peter N. Sedwick, David A. Hutchins
Iron Deficiency Increases Growth And Nitrogen-Fixation Rates Of Phosphorus-Deficient Marine Cyanobacteria, Nathan S. Garcia, Feixue Fu, Peter N. Sedwick, David A. Hutchins
OES Faculty Publications
Marine dinitrogen (N2)-fixing cyanobacteria have large impacts on global biogeochemistry as they fix carbon dioxide (CO2) and fertilize oligotrophic ocean waters with new nitrogen. Iron (Fe) and phosphorus (P) are the two most important limiting nutrients for marine biological N2 fixation, and their availabilities vary between major ocean basins and regions. A long-standing question concerns the ability of two globally dominant N2-fixing cyanobacteria, unicellular Crocosphaera and filamentous Trichodesmium, to maintain relatively high N2-fixation rates in these regimes where both Fe and P are typically scarce. We show that under P-deficient …
New Tracer To Estimate Community Predation Rates Of Phagotrophic Protists, Alexander B. Bochdansky, Melissa A. Clouse
New Tracer To Estimate Community Predation Rates Of Phagotrophic Protists, Alexander B. Bochdansky, Melissa A. Clouse
OES Faculty Publications
Predation of eukaryotic microbes on prokaryotes is one of the most important trophic interactions on Earth, representing a major mortality term and shaping morphology and composition of prokaryotic communities. Here we introduce and validate a new tracer to determine predation rates on prokaryotes. Minicells of Escherichia coli marked with a bright green fluorescent protein (GFP) vector have many operational advantages over previously used prey analogs such as fluorescently labeled bacteria. GFP-minicells are similar in size to naturally occurring bacteria from a variety of environments including the oligotrophic open ocean and the deep sea. They are relatively stable against microbial and …
Living On The Margin In The Anthropocene: Engagement Arenas For Sustainability Research And Action At The Ocean-Land Interface, B. C. Glavovic, K. Limburg, K-K. Liu, K-C. Emeis, H. Thomas, H. Kremer, B. Avril, J. Zhang, M. R. Mulholland, M. Glaser, D. P. Swaney
Living On The Margin In The Anthropocene: Engagement Arenas For Sustainability Research And Action At The Ocean-Land Interface, B. C. Glavovic, K. Limburg, K-K. Liu, K-C. Emeis, H. Thomas, H. Kremer, B. Avril, J. Zhang, M. R. Mulholland, M. Glaser, D. P. Swaney
OES Faculty Publications
The advent of the Anthropocene underscores the need to develop and implement transformative governance strategies that safeguard the Earth's life-support systems, most critically at the ocean-land interface - the Margin. The seaward realm of the Margin is the new frontier for resource exploitation and colonization to meet the needs of coastal nations and humanity overall. Here, we spotlight the pivotal role of the Margin for planetary resilience and sustainability, highlight priority issues, and outline a research strategy which aims to: (a) better understand Margin social-ecological systems; (b) guide sustainable development of Margin resources; (c) design governance regimes to reverse unsustainable …
Heterotrophic And Autotrophic Contribution To Dinitrogen Fixation In The Gulf Of Aqaba, Eyal Rahav, Barak Herut, Margaret R. Mulholland, Natalia Belkin, Hila Elifantz, Ilana Berman-Frank
Heterotrophic And Autotrophic Contribution To Dinitrogen Fixation In The Gulf Of Aqaba, Eyal Rahav, Barak Herut, Margaret R. Mulholland, Natalia Belkin, Hila Elifantz, Ilana Berman-Frank
OES Faculty Publications
We evaluated the seasonal contribution of heterotrophic and autotrophic diazotrophy to the total dinitrogen (N2) fixation in the photic zone of a pelagic station in the northern Gulf of Aqaba, Red Sea. N2 fixation rates were highest during a Trichodesmium bloom in winter (0.7 nmol N l-1 d-1), decreased 7-fold 1 wk later throughout the upper 200 m (~0.1 nmol N l-1) d-1), and were significantly coupled with both primary and bacterial productivity. N2 fixation rates were generally higher in the upper 200 m (~0.4 nmol N l-1 …
Protein Recycling In Bering Sea Algal Incubations, Eli K. Moore, H. Rodger Harvey, Jessica F. Faux, David R. Goodlett, Brook L. Nunn
Protein Recycling In Bering Sea Algal Incubations, Eli K. Moore, H. Rodger Harvey, Jessica F. Faux, David R. Goodlett, Brook L. Nunn
OES Faculty Publications
Protein present in phytoplankton represents a large fraction of the organic nitrogen and carbon transported from its synthesis in surface waters to marine sediments. Yet relatively little is known about the longevity of identifiable protein in situ, or the potential modifications to proteins that occur during bloom termination, protein recycling and degradation. To address this knowledge gap, diatom-dominated phytoplankton was collected during the Bering Sea spring blooms of 2009 and 2010, and incubated under darkness in separate shipboard degradation experiments spanning 11 and 53 d, respectively. In each experiment, the protein distribution was monited over time using shotgun proteomics, …
Uncoupling Between Dinitrogen Fixation And Primary Productivity In The Eastern Mediterranean Sea, Eyal Rahav, Barak Herut, Noga Stambler, Edo Bar-Zeev, Margaret R. Mulholland
Uncoupling Between Dinitrogen Fixation And Primary Productivity In The Eastern Mediterranean Sea, Eyal Rahav, Barak Herut, Noga Stambler, Edo Bar-Zeev, Margaret R. Mulholland
OES Faculty Publications
In the nitrogen (N)-impoverished photic zones of many oceanic regions, prokaryotic organisms fixing atmospheric dinitrogen (N2; diazotrophs) supply an essential source of new nitrogen and fuel primary production. We measured dinitrogen fixation and primary productivity (PP) during the thermally stratified summer period in different water regimes of the oligotrophic eastern Mediterranean Sea, including the Cyprus Eddy and the Rhodes Gyre. Low N2 fixation rates were measured (0.8-3.2μmol N m-2 d-1) excluding 10-fold higher rates in the Rhodes Gyre and Cyprus Eddy (~20μmol N m-2 d-1). The corresponding PP increased from east to west (200-2500μmol …
Effect Of Laser Ablation Depth In Otolith Life History Scans, Renée R. Hoover, Cynthia M. Jones
Effect Of Laser Ablation Depth In Otolith Life History Scans, Renée R. Hoover, Cynthia M. Jones
OES Faculty Publications
Life history scans of fish otoliths are bringing new insight into the structure, connectivity, and movement of fish populations. Data obtained from such scans, however, possess in-herent limitations that have not yet been fully addressed or understood. For example, several investigators have noted delays in otolith elemental uptake that do not appear to reflect habitat exposure. We hypothesized that the 3-dimensional structure of otoliths may produce sampling artifacts in the results obtained from laser ablation scans. To test this hypothesis, we sampled sagittal otoliths from juvenile Atlantic croaker Micropogonias undulatus with laser ablation inductively coupled plasma mass spectrometry to obtain …