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OES Faculty Publications

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Articles 61 - 90 of 198

Full-Text Articles in Marine Biology

Growth And Nitrogen Uptake Kinetics In Cultured Procentrum Donghaiense, Zhangxi Hu, Shunshan Duan, Margaret R. Mulholland Apr 2014

Growth And Nitrogen Uptake Kinetics In Cultured Procentrum Donghaiense, Zhangxi Hu, Shunshan Duan, Margaret R. Mulholland

OES Faculty Publications

We compared growth kinetics of Prorocentrum donghaiense cultures on different nitrogen (N) compounds including nitrate, ammonium urea, glutamic acid, dialanine, and cynate. P. donghaiense exhibited standard Monod-type growth kinetics over a range of nitrogen concentrations for all N. Compounds tested. Cultures grown on glu and urea had the highest maximum growth rates. However, cultures grown on cyanate had lower half saturation constants. Nitrogen uptake kinetics were measured in nitrate-deplete and replete batch cultures of P. donghaiense. In nitrate-deplete batch cultures, P. donghaiense exhibited Michaelis-Menten type uptake kinetics for nitrate, ammonium, urea and algal amino acids; uptake was saturated at …

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Reproductive Phase Determination In Male Meagre (Argyrosomus Regius, Sciaenidae): Testis Development And Histologic Corroboration Of A Gross Anatomical Scale, Nuno Prista, Leonel Gordo, Jose L. Costa, Maria J. Costa, Cynthia M. Jones Jan 2014

Reproductive Phase Determination In Male Meagre (Argyrosomus Regius, Sciaenidae): Testis Development And Histologic Corroboration Of A Gross Anatomical Scale, Nuno Prista, Leonel Gordo, Jose L. Costa, Maria J. Costa, Cynthia M. Jones

OES Faculty Publications

Reproductive stage determination of male gonads has received sparse attention in fish biology literature with few studies detailing the building of gross anatomical-and histologic scales. The meagre (Argyrosomus regius) is one of the world's largest sciaenids and supports a significant regional fishery in European and North African waters whose reproductive patterns are yet to be fully investigated. In the present study, we derive a macroscopic grading system for meagre testis using semi-quantitative graphs that feature the testis variability along the species size range and time of the year. We then describe the histological stages and reproductive phases of …

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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 Jan 2014

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 …

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Lack Of Equivalence In The Elemental And Stable Isotope Chemistry Within The Sagittal Otolith Pair Of The Summer Flounder, Paralichthys Dentatus, Antranik Kajajian, Jason J. Schaffler, Cynthia M. Jones Jan 2014

Lack Of Equivalence In The Elemental And Stable Isotope Chemistry Within The Sagittal Otolith Pair Of The Summer Flounder, Paralichthys Dentatus, Antranik Kajajian, Jason J. Schaffler, Cynthia M. Jones

OES Faculty Publications

In fish that are not bilaterally symmetrical, the left and right sagittae are often not symmetrical, exhibiting divergent growth patterns and mass, and may have differences in chemical composition. We investigated this in the asymmetrical summer flounder Paralichthys dentatus, collected from different nursery habitats along the US east coast. Significant differences were detected in otolith mass, δ13C, δ18O, Li:Ca, Mg:Ca, and Sr:Ca, and overall chemical signatures. These results refute the hypothesis of left-right equivalence that is prevalent for bilaterally symmetrical fishes. We tested whether a specific side was better suited for classification. The best models …

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Can We Predict The Future: Juvenile Finfish And Their Seagrass Nurseries In The Chesapeake Bay, Cynthia M. Jones Jan 2014

Can We Predict The Future: Juvenile Finfish And Their Seagrass Nurseries In The Chesapeake Bay, Cynthia M. Jones

OES Faculty Publications

The importance of estuarine seagrass beds as nurseries for juvenile fish has become a universal paradigm, especially for estuaries that are as important as the Chesapeake Bay. Yet, scientific tests of this hypothesis were equivocal depending on species, location, and metrics. Moreover, seagrasses themselves are under threat and one-third of seagrasses have disappeared worldwide with 65 of their losses occurring in estuaries. Although there have been extensive studies of seagrasses in the Chesapeake Bay, surprisingly few studies have quantified the relationship between seagrass as nurseries for finfish in the Bay. Of the few studies that have directly evaluated the use …

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Emergence Of Algal Blooms: The Effects Of Short-Term Variability In Water Quality On Phytoplankton Abundance, Diversity, And Community Composition In A Tidal Estuary, Todd A. Egerton, Ryan E. Morse, Harold G. Marshall, Margaret R. Mulholland Jan 2014

Emergence Of Algal Blooms: The Effects Of Short-Term Variability In Water Quality On Phytoplankton Abundance, Diversity, And Community Composition In A Tidal Estuary, Todd A. Egerton, Ryan E. Morse, Harold G. Marshall, Margaret R. Mulholland

OES Faculty Publications

Algal blooms are dynamic phenomena, often attributed to environmental parameters that vary on short timescales (e.g., hours to days). Phytoplankton monitoring programs are largely designed to examine long-term trends and interannual variability. In order to better understand and evaluate the relationships between water quality variables and the genesis of algal blooms, daily samples were collected over a 34 day period in the eutrophic Lafayette River, a tidal tributary within Chesapeake Bay's estuarine complex, during spring 2006. During this period two distinct algal blooms occurred; the first was a cryptomonad bloom and this was followed by a bloom of the mixotrophic …

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Fish Species Distribution In Seagrass Habitats Of Chesapeake Bay Are Structured By Abiotic And Biotic Factors, Jason J. Schaffler, Jacques Van Montfrans, Cynthia M. Jones, Robert J. Orth Jul 2013

Fish Species Distribution In Seagrass Habitats Of Chesapeake Bay Are Structured By Abiotic And Biotic Factors, Jason J. Schaffler, Jacques Van Montfrans, Cynthia M. Jones, Robert J. Orth

OES Faculty Publications

Seagrass habitats have long been known to serve as nursery habitats for juvenile fish by providing refuges from predation and areas of high forage abundance. However, comparatively less is known about other factors structuring fish communities that make extensive use of seagrass as nursery habitat. We examined both physical and biological factors that may structure the juvenile seagrass-associated fish communities across a synoptic-scale multiyear study in lower Chesapeake Bay. Across 3years of sampling, we collected 21,153 fish from 31 species. Silver Perch Bairdiella chrysoura made up over 86% of all individuals collected. Nine additional species made up at least 1% …

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Springtime Contribution Of Dinitrogen Fixation To Primary Production Across The Mediterranean Sea, E. Rahav, B. Herut, A. Levi, Margaret Mulholland, I. Berman-Frank May 2013

Springtime Contribution Of Dinitrogen Fixation To Primary Production Across The Mediterranean Sea, E. Rahav, B. Herut, A. Levi, Margaret Mulholland, I. Berman-Frank

OES Faculty Publications

Dinitrogen (N-2) fixation rates were measured during early spring across the different provinces of Mediterranean Sea surface waters. N-2 fixation rates, measured using N-15(2) enriched seawater, were lowest in the eastern basin and increased westward with a maximum at the Strait of Gibraltar (0.10 to 2.35 nmol NL-1 d(-1), respectively). These rates were 3-7 fold higher than N-2 fixation rates measured previously in the Mediterranean Sea during summertime and we estimated that methodological differences alone did not account for the seasonal changes we observed. Higher contribution of N-2 fixation to primary production (4-8 %) was measured in the western basin …

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Phosphorus Cycling In The Sargasso Sea: Investigation Using The Oxygen Isotopic Composition Of Phosphate, Enzyme-Labeled Fluorescence, And Turnover Times, Karen Mclaughlin, Jill A. Sohm, Gregory A. Cutter, Michael W. Lomas, Adina Paytan Jan 2013

Phosphorus Cycling In The Sargasso Sea: Investigation Using The Oxygen Isotopic Composition Of Phosphate, Enzyme-Labeled Fluorescence, And Turnover Times, Karen Mclaughlin, Jill A. Sohm, Gregory A. Cutter, Michael W. Lomas, Adina Paytan

OES Faculty Publications

Dissolved inorganic phosphorus (DIP) concentrations in surface water of vast areas of the ocean are extremely low (<10 nM) and phosphorus (P) availability could limit primary productivity in these regions. We explore the use of oxygen isotopic signature of dissolved phosphate (δ18OPO4) to investigate biogeochemical cycling of P in the Sargasso Sea, Atlantic Ocean. Additional techniques for studying P dynamics including 33P-based DIP turnover time estimates and percent of cells expressing alkaline phosphatase (AP) activity as measured by enzyme-labeling fluorescence are also used. In surface waters, δ18OPO4 values were lower than equilibrium by 3–6%, indicative of dissolved organic phosphorous (DOP) remineralization by extracellular enzymes. An isotope mass balance model using a variety of possible combinations of …

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Using Ammonium Pore Water Profiles To Assess Stoichiometry Of Deep Remineralization Processes In Methanogenic Continental Margin Sediments, David J. Burdige, Tomoko Komada Jan 2013

Using Ammonium Pore Water Profiles To Assess Stoichiometry Of Deep Remineralization Processes In Methanogenic Continental Margin Sediments, David J. Burdige, Tomoko Komada

OES Faculty Publications

In many continental margin Sediments, a deep reaction zone exists which is separated from remineralization processes near the sediment surface. Here, methane diffuses upward to a depth where it is oxidized by downwardly diffusing sulfate. However, the methane sources that drive this anaerobic oxidation of methane (AOM) in the sulfate-methane transition zone (SMT) may vary among sites. In particular, these sources can be thought of as either (i) "internal" sources from in situ methanogenesis (regardless of where it occurs in the sediment column) that are ultimately coupled to organic matter deposition and burial, or (ii) "external" sources such as hydrocarbon …

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Diatom Proteomics Reveals Unique Acclimation Strategies To Mitigate Fe Limitation, Brook L. Nunn, Jessica F. Faux, Anna A. Hippman, Maria T. Maldonado, H. Rodger Harvey, David R. Goodlett, Philip W. Boyd, Robert F. Strzepek Jan 2013

Diatom Proteomics Reveals Unique Acclimation Strategies To Mitigate Fe Limitation, Brook L. Nunn, Jessica F. Faux, Anna A. Hippman, Maria T. Maldonado, H. Rodger Harvey, David R. Goodlett, Philip W. Boyd, Robert F. Strzepek

OES Faculty Publications

Phytoplankton growth rates are limited by the supply of iron (Fe) in approximately one third of the open ocean, with major implications for carbon dioxide sequestration and carbon (C) biogeochemistry. To date, understanding how alteration of Fe supply changes phytoplankton physiology has focused on traditional metrics such as growth rate, elemental composition, and biophysical measurements such as photosynthetic competence (Fv/Fm). Researchers have subsequently employed transcriptomics to probe relationships between changes in Fe supply and phytoplankton physiology. Recently, studies have investigated longer-term (i.e. following acclimation) responses of phytoplankton to various Fe conditions. In the present study, the coastal diatom, Thalassiosira pseudonana, …

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Effect Of Laser Ablation Depth In Otolith Life History Scans, Renée R. Hoover, Cynthia M. Jones Jan 2013

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 …

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Wintering Eiders Acquire Exceptional Se And Cd Burdens In The Bering Sea: Physiological And Oceanographic Factors, James R. Lovvorn, Merl F. Raisbeck, Lee W. Cooper, Gregory A. Cutter, Micah W. Miller, Marjorie L. Brooks, Jacqueline M. Grebmeier, Angela C. Matz, Cortney M. Schaefer Jan 2013

Wintering Eiders Acquire Exceptional Se And Cd Burdens In The Bering Sea: Physiological And Oceanographic Factors, James R. Lovvorn, Merl F. Raisbeck, Lee W. Cooper, Gregory A. Cutter, Micah W. Miller, Marjorie L. Brooks, Jacqueline M. Grebmeier, Angela C. Matz, Cortney M. Schaefer

OES Faculty Publications

During late winter (March) in the Bering Sea, levels of Se in livers and Cd in kidneys of spectacled eiders Somateria fischeri were exceptionally high (up to 489 and 312 µg g−1 dry mass, respectively). Comparison of organ and blood samples during late winter, early spring migration, and breeding suggests that the eiders’ high Se and Cd burdens were accumulated at sea, with highest exposure during winter. High exposure may have resulted from high metabolic demands and food intake, as well as concentrations in food. In the eiders’ remote wintering area, their bivalve prey contained comparable Se levels and …

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Combined Effects Of Co2 And Light On Large And Small Isolates Of The Unicellular N2-Fixing Cyanobacterium Crocosphaera Watsonii From The Western Tropical Atlantic Ocean, Nathan S. Garcia, Fei-Xue Fu, Cynthia L. Breene, Elizabeth K. Yu, Peter W. Bernhardt, Margaret R. Mulholland, David A. Hutchins Jan 2013

Combined Effects Of Co2 And Light On Large And Small Isolates Of The Unicellular N2-Fixing Cyanobacterium Crocosphaera Watsonii From The Western Tropical Atlantic Ocean, Nathan S. Garcia, Fei-Xue Fu, Cynthia L. Breene, Elizabeth K. Yu, Peter W. Bernhardt, Margaret R. Mulholland, David A. Hutchins

OES Faculty Publications

We examined the combined effects of light and pCO2 on growth, CO2-fixation and N2-fixation rates by strains of the unicellular marine N2-fixing cyanobacterium Crocosphaera watsonii with small (WH0401) and large (WH0402) cells that were isolated from the western tropical Atlantic Ocean. In low-pCO2-acclimated cultures (190ppm) of WH0401, growth, CO2-fixation and N2-fixation rates were significantly lower than those in cultures acclimated to higher (present-day approximate to 385ppm, or future approximate to 750ppm) pCO2 treatments. Growth rates were not significantly different, however, in low-pCO2-acclimated cultures of …

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Bacterial Colonization And Extinction On Marine Aggregates: Stochastic Model Of Species Presence And Abundance, Andrew M. Kramer, M. Maille Lyons, Fred C. Dobbs, John M. Drake Jan 2013

Bacterial Colonization And Extinction On Marine Aggregates: Stochastic Model Of Species Presence And Abundance, Andrew M. Kramer, M. Maille Lyons, Fred C. Dobbs, John M. Drake

OES Faculty Publications

Organic aggregates provide a favorable habitat for aquatic microbes, are efficiently filtered by shellfish, and may play a major role in the dynamics of aquatic pathogens. Quantifying this role requires understanding how pathogen abundance in the water and aggregate size interact to determine the presence and abundance of pathogen cells on individual aggregates. We build upon current understanding of the dynamics of bacteria and bacterial grazers on aggregates to develop a model for the dynamics of a bacterial pathogen species. The model accounts for the importance of stochasticity and the balance between colonization and extinction. Simulation results suggest that while …

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Evaluation Of Electrophoretic Protein Extraction And Database-Driven Protein Identification From Marine Sediments, Eli K. Moore, Brook L. Nunn, Jessica F. Faux, David R. Goodlett, H. Rodger Harvey May 2012

Evaluation Of Electrophoretic Protein Extraction And Database-Driven Protein Identification From Marine Sediments, Eli K. Moore, Brook L. Nunn, Jessica F. Faux, David R. Goodlett, H. Rodger Harvey

OES Faculty Publications

Intact proteins comprise a major component of organic carbon and nitrogen produced globally and are likely an important fraction of organic matter in sediments and soils. Extracting the protein component from sediments and soils for mass spectral characterization and identification represents a substantial challenge given the range of products and functionalities present in the complex matrix. Multiple forms of gel electrophoresis were evaluated as a means of enhancing recovery of sedimentary protein before proteomic characterization and compared with a direct enzymatic digestion of proteins in sediments. Resulting tryptic peptides were analyzed using shotgun proteomics and tandem mass spectra were evaluated …

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Δ13c Is A Signature Of Light Availability And Photosynthesis In Seagrass, Xingping Hu, David J. Burdige, Richard C. Zimmerman Jan 2012

Δ13c Is A Signature Of Light Availability And Photosynthesis In Seagrass, Xingping Hu, David J. Burdige, Richard C. Zimmerman

OES Faculty Publications

We explored the role of light-saturated (carbon-limited) photosynthesis on δ¹³C of turtlegrass (Thalassia testudinum Banks ex Konig) populations from the clear, blue waters of the Great Bahama Bank and the turbid, green waters of Florida Bay using field observations and radiative transfer models. Consistent with numerous previous observations, leaf δ¹³C decreased significantly with water depth in both regions. However the δ¹³C for Bahamas turtlegrass was 3 parts per thousand heavier than that for Florida Bay turtlegrass at equivalent depths, and broadband irradiance explained even less of the δ¹³C variations than depth. Instead, leaf δ¹³C showed a stronger relationship to …

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An Introduction To Ecology Of Infectious Diseases - Oysters And Estuaries, Eileen E. Hofmann, Susan E. Ford Jan 2012

An Introduction To Ecology Of Infectious Diseases - Oysters And Estuaries, Eileen E. Hofmann, Susan E. Ford

OES Faculty Publications

Infectious diseases are recognized as an important factor regulating marine ecosystems (Harvell et al., 1999, 2002, 2004; Porter et al., 2001; McCallum et al., 2004; Ward and Lafferty, 2004; Stewart et al., 2008; Bienfang et al., 2011). Many of the organisms affected by marine diseases have important ecological roles in estuarine and coastal environments and some are also commercially important. Outbreaks of infectious diseases in these environments, referred to as epizootics, can produce significant population declines and extinctions, both of which threaten biodiversity, food web interactions, and ecosystem productivity (Harvell et al., 2002, 2004).

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The Role Of Larval Dispersal In Metapopulation Gene Flow: Local Population Dynamics Matter, Daphne M. Munroe, John M. Klinck, Eileen E. Hofmann, Eric N. Powell Jan 2012

The Role Of Larval Dispersal In Metapopulation Gene Flow: Local Population Dynamics Matter, Daphne M. Munroe, John M. Klinck, Eileen E. Hofmann, Eric N. Powell

OES Faculty Publications

The degree of genetic connectivity among populations in a metapopulation has direct consequences for species evolution, development of disease resistance, and capacity of a metapopulation to adapt to climate change. This study used a metapopulation model that integrates population dynamics, dispersal, and genetics within an individual-based model framework to examine the mechanisms and dynamics of genetic connectivity within a metapopulation. The model was parameterized to simulate four populations of oysters (Crassostrea virginica) from Delaware Bay on the mid-Atlantic coast of the United States. Differences among the four populations include a strong spatial gradient in mortality, a spatial gradient …

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Database Of Diazotrophs In Global Ocean: Abundance, Biomass, And Nitrogen Fixation Rates, Y. W. Luo, S. C. Doney, L. A. Anderson, M. Benavides, I. Berman-Frank, A. Bode, S. Bonnet, K. H. Boström, D. Böttjer, D. G. Capone, M. R. Mulholland Jan 2012

Database Of Diazotrophs In Global Ocean: Abundance, Biomass, And Nitrogen Fixation Rates, Y. W. Luo, S. C. Doney, L. A. Anderson, M. Benavides, I. Berman-Frank, A. Bode, S. Bonnet, K. H. Boström, D. Böttjer, D. G. Capone, M. R. Mulholland

OES Faculty Publications

Marine N2 fixing microorganisms, termed di-azotrophs, are a key functional group in marine pelagic ecosystems. The biological fixation of dinitrogen (N2) to bioavailable nitrogen provides an important new source of nitrogen for pelagic marine ecosystems and influences primary productivity and organic matter export to the deep ocean. As one of a series of efforts to collect biomass and rates specific to different phytoplankton functional groups, we have constructed a database on diazotrophic organisms in the global pelagic upper ocean by compiling about 12 000 direct field measurements of cyanobacterial diazotroph abundances (based on microscopic cell counts or …

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Controls On Dissolved Cobalt In Surface Waters Of The Sargasso Sea: Comparisons With Iron And Aluminum, R. U. Shelley, Peter N. Sedwick, T. S. Bibby, P. Cabedo-Sanz, T. M. Church, R. J. Johnson, A. I. Macey, C. M. Marsay, E. R. Sholkovitz, S. J. Ussher, P. J. Worsfold, M. C. Lohan Jan 2012

Controls On Dissolved Cobalt In Surface Waters Of The Sargasso Sea: Comparisons With Iron And Aluminum, R. U. Shelley, Peter N. Sedwick, T. S. Bibby, P. Cabedo-Sanz, T. M. Church, R. J. Johnson, A. I. Macey, C. M. Marsay, E. R. Sholkovitz, S. J. Ussher, P. J. Worsfold, M. C. Lohan

OES Faculty Publications

Dissolved cobalt (dCo), iron (dFe) and aluminum (dAl) were determined in water column samples along a meridional transect (∼31°N to 24°N) south of Bermuda in June 2008. A general north-to-south increase in surface concentrations of dFe (0.3-1.6 nM) and dAl (14-42 nM) was observed, suggesting that aerosol deposition is a significant source of dFe and dAl, whereas no clear trend was observed. for near-surface dCo concentrations. Shipboard aerosol samples indicate fractional solubility values of 8-100% for aerosol Co, which are significantly higher than corresponding estimates of the solubility of aerosol Fe (0.44-45%). Hydrographic observations and analysis of time series rain …

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Anaerobic Oxidation Of Methane And The Stoichiometry Of Remineralization Processes In Continental Margin Sediments, David J. Burdige, Tomoko Kamada Jan 2011

Anaerobic Oxidation Of Methane And The Stoichiometry Of Remineralization Processes In Continental Margin Sediments, David J. Burdige, Tomoko Kamada

OES Faculty Publications

In many coastal and continental margin sediments, pore-water property-property plots yield values of rc:s, the stoichiometric ratio of dissolved inorganic carbon (DIC) produced to sulfate reduced, that are lower than the commonly assumed value of 2. Remineralization of organic matter more reduced than CH2O can cause such observations, as can DIC loss due to authigenic carbonate precipitation. However, through studies of Santa Monica Basin sediments, we have observed that these observations could also be related to the occurrence of anaerobic oxidation of methane (AOM) in sediments. Specifically, using a reactive transport sediment model, we have shown …

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Abundance Of Eukaryotic Microbes In The Deep Subtropical North Atlantic, Danielle Morgan-Smith, Gerhard J. Herndl, Hendrik M. Van Aken, Alexander B. Bochdansky Jan 2011

Abundance Of Eukaryotic Microbes In The Deep Subtropical North Atlantic, Danielle Morgan-Smith, Gerhard J. Herndl, Hendrik M. Van Aken, Alexander B. Bochdansky

OES Faculty Publications

The meso- and bathypelagic ocean comprises the largest habitat on earth, yet we know very little about the distribution and activity of protists in this environment. These small eukaryotes are responsible for controlling bacterial abundance in the surface ocean and are major players in the material and energy transfer of pelagic food webs. In this paper, we quantify microbial eukaryotes in the deep North Atlantic, as well as provide a basic characterization of eukaryote community changes through the water column. To this end, we counted organisms using 2 different approaches: (1) catalyzed reporter deposition fluorescence in situ hybridization (CARD-FISH, also …

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Cascading Migrations And Implications For Vertical Fluxes In Pelagic Ecosystems, Stephen M. Bollens, Gretchen Rollwagen-Bollens, Joel A. Quenette, Alexander B. Bochdansky Jan 2011

Cascading Migrations And Implications For Vertical Fluxes In Pelagic Ecosystems, Stephen M. Bollens, Gretchen Rollwagen-Bollens, Joel A. Quenette, Alexander B. Bochdansky

OES Faculty Publications

Diel vertical migration is widespread across diverse taxa in the world's lakes and seas, yet its biogeochemical consequences are still poorly understood. The biologically mediated vertical flux of material in the ocean (also known as the "biological pump") is a matter of major interest and concern, as it is thought to play an important role in regulating ocean carbon storage, and by extension, the global carbon cycle. Recent studies spanning multiple trophic levels from fish to dinoflagellates have led us to a concept of coupled vertical migrations that we refer to as "cascading migrations". That is, migrations that …

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Draft Genome Sequence Of Strain Himb100, A Cultured Representative Of The Sar116 Clade Of Marine Alphaproteobacteria, Jana Grote, Cansu Bayindirli, Kristin Bergauer, Paula C. De Moraes, Huan Chen, Lindsay D'Ambrosio, Bethany Edwards, Beatriz Fernandez-Gomez, Mariam Hamisi, Dan Nguyen, Yoshimi M. Rii, Emily Saeck, Charles Schutte, Brittany Widner Jan 2011

Draft Genome Sequence Of Strain Himb100, A Cultured Representative Of The Sar116 Clade Of Marine Alphaproteobacteria, Jana Grote, Cansu Bayindirli, Kristin Bergauer, Paula C. De Moraes, Huan Chen, Lindsay D'Ambrosio, Bethany Edwards, Beatriz Fernandez-Gomez, Mariam Hamisi, Dan Nguyen, Yoshimi M. Rii, Emily Saeck, Charles Schutte, Brittany Widner

OES Faculty Publications

Strain HIMB100 is a planktonic marine bacterium in the class Alphaproteobacteria. This strain is of interest because it is one of the first known isolates from a globally ubiquitous clade of marine bacteria known as SAR116 within the family Rhodospirillaceae. Here we describe preliminary features of the organism, together with the draft genome sequence and annotation. This is the second genome sequence of a member of the SAR116 clade. The 2,458,945 bp genome contains 2,334 protein-coding and 42 RNA gene

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Characterization Of Putative Iron Responsive Genes As Species-Specific Indicators Of Iron Stress In Thalassiosiroid Diatoms, Leann P. Whitney, Jeremy J. Lins, Margaret P. Hughes, Mark L. Wells, P. Dreux Chappell Jan 2011

Characterization Of Putative Iron Responsive Genes As Species-Specific Indicators Of Iron Stress In Thalassiosiroid Diatoms, Leann P. Whitney, Jeremy J. Lins, Margaret P. Hughes, Mark L. Wells, P. Dreux Chappell

OES Faculty Publications

Iron (Fe) availability restricts diatom growth and primary production in large areas of the oceans. It is a challenge to assess the bulk Fe nutritional health of natural diatom populations, since species can differ in their physiological and molecular responses to Fe limitation. We assayed expression of selected genes in diatoms from the Thalassiosira genus to assess their potential utility as species-specific molecular markers to indicate Fe status in natural diatom assemblages. In this study, we compared the expression of the photosynthetic genes encoding ferredoxin (a Fe-requiring protein) and flavodoxin (a Fe-free protein) in culture experiments with Fe replete and …

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Benthic Ecology From Space: Optics And Net Primary Production In Seagrass And Benthic Algae Across The Great Bahama Bank, Heidi M. Dierssen, Richard C. Zimmerman, Lisa A. Drake, David J. Burdige Jan 2010

Benthic Ecology From Space: Optics And Net Primary Production In Seagrass And Benthic Algae Across The Great Bahama Bank, Heidi M. Dierssen, Richard C. Zimmerman, Lisa A. Drake, David J. Burdige

OES Faculty Publications

Development of repeatable and quantitative tools are necessary for determining the abundance and distribution of different types of benthic habitats, detecting changes to these ecosystems, and determining their role in the global carbon cycle. Here we used ocean color remote sensing techniques to map different major groups of primary producers and estimate net primary productivity (NPP) across Great Bahama Bank (GBB). Field investigations on the northern portion of the GBB in 2004 revealed 3 dominant types of benthic primary producers: seagrass, benthic macroalgae, and microalgae attached to sediment. Laboratory measurements of NPP ranged from barely net autotrophic for grapestone sediment …

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Modeling The Vertical Distributions Of Downwelling Plane Irradiance And Diffuse Attenuation Coefficient In Optically Deep Waters, X. J. Pan, Richard C. Zimmerman Jan 2010

Modeling The Vertical Distributions Of Downwelling Plane Irradiance And Diffuse Attenuation Coefficient In Optically Deep Waters, X. J. Pan, Richard C. Zimmerman

OES Faculty Publications

The diffuse attenuation coefficient Kᵈ is critical to understand the vertical distribution of underwater downwelling irradiance (Eᵈ). Theoretically Eᵈ is composed of the direct solar beam and the diffuse sky irradiance. Applying the statistical results from Hydrolight radiative transfer simulations, Kᵈ is expressed into a mathematical equation (named as PZ06) integrated from the contribution of direct solar beam and diffuse sky irradiance with the knowledge of sky and water conditions. The percent root mean square errors (RMSE) for the vertical distribution of Eᵈ(z) under various sky and water conditions between PZ06 and Hydrolight results are typically less than 4%. Field …

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The Path To Preservation: Using Proteomics To Decipher The Fate Of Diatom Proteins During Microbial Degradation, Brook L. Nunn, Ying S. Ting, Lars Malmström, Yihsuan S. Tsai, Angela Aquier, David R. Goodlett, H. Rodger Harvey Jan 2010

The Path To Preservation: Using Proteomics To Decipher The Fate Of Diatom Proteins During Microbial Degradation, Brook L. Nunn, Ying S. Ting, Lars Malmström, Yihsuan S. Tsai, Angela Aquier, David R. Goodlett, H. Rodger Harvey

OES Faculty Publications

We drew upon recent advances in tandem mass spectrometry-based proteomic analyses in order to examine the proteins that remain after a diatom bloom enters the stationary phase, precipitates out of the photic zone, and is subjected to microbial degradation over a 23-d period within a controlled laboratory environment. Proteins were identified from tandem mass spectra searched against three different protein databases in order to track proteins from Thalassiosira pseudonana and any potential bacterial contributions. A rapid loss of diatom protein was observed over the incubation period; 75% of the proteins initially identified were not detected after 72 h of exposure …

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Effect Of The Heterotrophic Dinoflagellate Oxyrrhis Marina And The Copepod Acartia Tonsa On Vertical Carbon Flux In And Around Thin Layers Of The Phytoflagellate Isochrysis Galbana, A. B. Bochdansky, S. M. Bollens, G. C. Rollwagen-Bollens, A. H. Gibson Jan 2010

Effect Of The Heterotrophic Dinoflagellate Oxyrrhis Marina And The Copepod Acartia Tonsa On Vertical Carbon Flux In And Around Thin Layers Of The Phytoflagellate Isochrysis Galbana, A. B. Bochdansky, S. M. Bollens, G. C. Rollwagen-Bollens, A. H. Gibson

OES Faculty Publications

Dynamics of material and energy flow through food webs differ when resources are allocated in patches in comparison to situations in which the same resources are distributed evenly throughout the water column. Thin layers of plankton are special cases of such resource patches. While previous studies have predominantly focused on the response of organisms to these layers, we investigated how 2 types of grazers in turn affect thin layers. In an experimental study with tightly controlled environmental conditions, we monitored the redistribution of particulate organic (POC), dissolved organic (DOC) and inorganic (DIC) carbon from thin layers of Isochrysis galbana. …

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