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VIMS Articles

2013

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Articles 1 - 30 of 55

Full-Text Articles in Life Sciences

Ecosystem Effects Of Shell Aggregations And Cycling In Coastal Waters: An Example Of Chesapeake Bay Oyster Reefs, G G. Waldbusser, E N. Powell, Roger L. Mann Apr 2013

Ecosystem Effects Of Shell Aggregations And Cycling In Coastal Waters: An Example Of Chesapeake Bay Oyster Reefs, G G. Waldbusser, E N. Powell, Roger L. Mann

VIMS Articles

Disease, overharvesting, and pollution have impaired the role of bivalves on coastal ecosystems, some to the point of functional extinction. An underappreciated function of many bivalves in these systems is shell formation. The ecological significance of bivalve shell has been recognized; geochemical effects are now more clearly being understood. A positive feedback exists between shell aggregations and healthy bivalve populations in temperate estuaries, thus linking population dynamics to shell budgets and alkalinity cycling. On oysterreefs a balanced shell budget requires healthy long-lived bivalves to maximize shell input permortality event thereby countering shell loss. Active and dense populations of filter-feeding bivalves ...


Temporal Shifts In Top-Down Vs. Bottom-Up Control Of Epiphytic Algae In A Seagrass Ecosystem, Ma Whalen, Je Duffy, Jb Grace Feb 2013

Temporal Shifts In Top-Down Vs. Bottom-Up Control Of Epiphytic Algae In A Seagrass Ecosystem, Ma Whalen, Je Duffy, Jb Grace

VIMS Articles

In coastal marine food webs, small invertebrate herbivores (mesograzers) have long been hypothesized to occupy an important position facilitating dominance of habitat-forming macrophytes by grazing competitively superior epiphytic algae. Because of the difficulty of manipulating mesograzers in the field, however, their impacts on community organization have rarely been rigorously documented. Understanding mesograzer impacts has taken on increased urgency in seagrass systems due to declines in seagrasses globally, caused in part by widespread eutrophication favoring seagrass overgrowth by faster-growing algae. Using cage-free field experiments in two seasons (fall and summer), we present experimental confirmation that mesograzer reduction and nutrients can promote ...


Multiple Predator Species Alter Prey Behavior, Population Growth, And A Trophic Cascade In A Model Estuarine Food Web, Pl Reynolds, Jf Bruno Feb 2013

Multiple Predator Species Alter Prey Behavior, Population Growth, And A Trophic Cascade In A Model Estuarine Food Web, Pl Reynolds, Jf Bruno

VIMS Articles

Predators can influence prey population dynamics by affecting prey behaviors with strong fitness consequences, with cascading effects on lower trophic levels. Here, we demonstrate that multiple predator species can nonconsumptively influence prey population growth and the strength of a trophic cascade in a model marine community. We exposed the herbivorous amphipod Ampithoe longimana to olfactory and visual cues from three common predators (pinfish, mud crabs, brown shrimp) singly and together in a multiple-predator assemblage to quantify the nonconsumptive effects (NCEs) of predator identity and the presence of multiple predators on prey population and community-level metrics. The presence of predator cues ...


Envisioning A Marine Biodiversity Observation Network, Je Duffy, La Amaral-Zettler, Dg Fautin, G Paulay, Ta Rynearson, Et Al. Jan 2013

Envisioning A Marine Biodiversity Observation Network, Je Duffy, La Amaral-Zettler, Dg Fautin, G Paulay, Ta Rynearson, Et Al.

VIMS Articles

Humans depend on diverse ocean ecosystems for food, jobs, and sustained well-being, yet many stressors threaten marine life. Extensive research has demonstrated that maintaining biodiversity promotes ocean health and service provision; therefore, monitoring the status and trends of marine biodiversity is important for effective ecosystem management. However, there is no systematic sustained program for evaluating ocean biodiversity. Coordinating existing monitoring and building a proactive marine biodiversity observation network will support efficient, economical resource management and conservation and should be a high priority. A synthesis of expert opinions suggests that, to be most effective, a marine biodiversity observation network should integrate ...


Oyster-Mediated Benthic-Pelagic Coupling Modifies Nitrogen Pools And Processes, Ar Smyth, Nr Geraldi, Mf Piehler Jan 2013

Oyster-Mediated Benthic-Pelagic Coupling Modifies Nitrogen Pools And Processes, Ar Smyth, Nr Geraldi, Mf Piehler

VIMS Articles

Removal of nitrogen through enhanced denitrification has been identified as an ecosystem service provided by oysters. In this study, we assessed the effects of an individual oyster (Crassostrea virginica) on nitrogen dynamics. Fluxes of N-2, O-2, nitrate/nitrite (NOx) and ammonium (NH4+) were measured from continuous-flow microcosms that contained a live oyster, sediment, or a live oyster + sediment. Net N-2 fluxes were indicative of nitrogen fixation in the sediment treatment and denitrification in the oyster and oyster + sediment treatments. Organic matter de position and ammonium production associated with oyster biodeposits and excretion likely decreased N limitation, and thus the demand ...


Biodiversity In A Changing Climate: A Synthesis Of Current And Projected Trends In The Us, Md Staudinger, Sl Carter, Ms Cross, Ns Dubois, Je Duffy, Et Al. Jan 2013

Biodiversity In A Changing Climate: A Synthesis Of Current And Projected Trends In The Us, Md Staudinger, Sl Carter, Ms Cross, Ns Dubois, Je Duffy, Et Al.

VIMS Articles

This paper provides a synthesis of the recent literature describing how global biodiversity is being affected by climate change and is projected to respond in the future. Current studies reinforce earlier findings of major climate-change-related impacts on biological systems and document new, more subtle after-effects. For example, many species are shifting their distributions and phenologies at faster rates than were recorded just a few years ago; however, responses are not uniform across species. Shifts have been idiosyncratic and in some cases counterintuitive, promoting new community compositions and altering biotic interactions. Although genetic diversity enhances species' potential to respond to variable ...


Visual Acuity In Pelagic Fishes And Mollusks, Yl Gagnon, Tt Sutton, S Johnsen Jan 2013

Visual Acuity In Pelagic Fishes And Mollusks, Yl Gagnon, Tt Sutton, S Johnsen

VIMS Articles

In the sea, visual scenes change dramatically with depth. At shallow and moderate depths (<1000 >m), there is enough light for animals to see the surfaces and shapes of prey, predators, and conspecifics. This changes below 1000 m, where no downwelling daylight remains and the only source of light is bioluminescence. These different visual scenes require different visual adaptations and eye morphologies. In this study we investigate how the optical characteristics of animal lenses correlate with depth and ecology. We measured the radius, focal length, and optical quality of the lenses of pelagic fishes, cephalopods, and a gastropod using a custom-built ...


The Importance Of Dissimilatory Nitrate Reduction To Ammonium (Dnra) In The Nitrogen Cycle Of Coastal Ecosystems, Ae Giblin, Cr Tobias, Bk Song, N Weston, Gt Banta Jan 2013

The Importance Of Dissimilatory Nitrate Reduction To Ammonium (Dnra) In The Nitrogen Cycle Of Coastal Ecosystems, Ae Giblin, Cr Tobias, Bk Song, N Weston, Gt Banta

VIMS Articles

Until recently, it was believed that biological assimilation and gaseous nitrogen (N) loss through denitrification were the two major fates of nitrate entering or produced within most coastal ecosystems. Denitrification is often viewed as an important ecosystem service that removes reactive N from the ecosystem. However, there is a competing nitrate reduction process, dissimilatory nitrate reduction to ammonium (DNRA), that conserves N within the ecosystem. The recent application of nitrogen stable isotopes as tracers has generated growing evidence that DNRA is a major nitrogen pathway that cannot be ignored. Measurements comparing the importance of denitrification vs. DNRA in 55 coastal ...


Penguin Biogeography Along The West Antarctic Peninsula Testing The Canyon Hypothesis With Palmer Lter Observations, O Schofield, H Ducklow, K Bernard, S Doney, D Patterson-Fraser, Et Al. Jan 2013

Penguin Biogeography Along The West Antarctic Peninsula Testing The Canyon Hypothesis With Palmer Lter Observations, O Schofield, H Ducklow, K Bernard, S Doney, D Patterson-Fraser, Et Al.

VIMS Articles

No abstract provided.


Effects Of Microalgal Exudates And Intact Cells On Subtropical Marine Zooplankton, Nj Silva, Kw Tang, Rm Lopes Jan 2013

Effects Of Microalgal Exudates And Intact Cells On Subtropical Marine Zooplankton, Nj Silva, Kw Tang, Rm Lopes

VIMS Articles

Harmful algal blooms (HABs) affect coastal waters worldwide and very often lead to the disruption of seafood harvesting and commercial activities, because of potential hazards to human health associated with the consumption of contaminated mussels, crustaceans and fish. HAB events are frequently caused by outbreaks of toxin-producing dinoflagellates, which are subject to top-down control by zooplankton. The aim of this study was to analyze the effects of dinoflagellate exudates and intact cells on the survivorship and mobility of zooplankton taxa from a subtropical location (Ubatuba, Brazil). Lethal effects were observed in five out of six taxa investigated, three of which ...


Projected Hg Dietary Exposure Of 3 Bird Species Nesting On A Contaminated Floodplain (South River, Virginia, Usa), Jc Wang, Mc Newman Jan 2013

Projected Hg Dietary Exposure Of 3 Bird Species Nesting On A Contaminated Floodplain (South River, Virginia, Usa), Jc Wang, Mc Newman

VIMS Articles

Dietary Hg exposure was modeled for Carolina wren (Thryothorus ludovicianus), Eastern song sparrow (Melospiza melodia), and Eastern screech owl (Otus asio) nesting on the contaminated South River floodplain (Virginia, USA). Parameterization of Monte-Carlo models required formal expert elicitation to define bird body weight and feeding ecology characteristics because specific information was either unavailable in the published literature or too difficult to collect reliably by field survey. Mercury concentrations and weights for candidate food items were obtained directly by field survey. Simulations predicted the probability that an adult bird during breeding season would ingest specific amounts of Hg during daily foraging ...


Habitat Associations And Dispersal Of Black Sea Bass From A Mid-Atlantic Bight Reef, Mary C. Fabrizio, John P. Manderson, Jeffrey P. Pessutti Jan 2013

Habitat Associations And Dispersal Of Black Sea Bass From A Mid-Atlantic Bight Reef, Mary C. Fabrizio, John P. Manderson, Jeffrey P. Pessutti

VIMS Articles

We examined habitat associations of 122 adult black sea bass Centropristis striata at a temperate reef off the coast of New Jersey, USA. The study site, located within the Historic Area Remediation Site, encompassed 46.1 km2 and included areas of rocky bottom and highly variable bathymetry. Factors influencing dispersal and habitat use were determined from acoustic tele - metry data collected between May and December 2003 from a grid of 72 moored receivers. About 2.7 times as many black sea bass used the site in summer as in fall. Fish were associated with relatively shallow, complex habitats characterized by ...


Broad-Scale Association Between Seagrass Cover And Juvenile Blue Crab Density In Chesapeake Bay, Gina M. Ralph, Rd Seitz, R J. Orth, Kathleen E. Knick, Rom Lipcius Jan 2013

Broad-Scale Association Between Seagrass Cover And Juvenile Blue Crab Density In Chesapeake Bay, Gina M. Ralph, Rd Seitz, R J. Orth, Kathleen E. Knick, Rom Lipcius

VIMS Articles

Although numerous small-scale laboratory, mesocosm, and field experiments have demonstrated that abundance, survival, and growth of juvenile fish and invertebrates are higher in vegetated than in unvegetated habitats, the effect of habitat quality (i.e. habitat complexity) within vegetated habitats has not been documented at a broad spatial scale. We examined the relationship between percent cover in seagrass beds (eelgrass Zostera marina, widgeon grass Ruppia maritima, and associated macroalgae) and juvenile blue crab Callinectes sapidus density at a broad spatial scale. We quantified the functional relationship between juvenile density and percent cover of vegetation by sampling in Chesapeake Bay (USA ...


Migratory And Within-Estuary Behaviors Of Adult Summer Flounder (Paralichthys Dentatus) In A Lagoon System Of The Southern Mid-Atlantic Bight, Karen M. Capossela, Mary C. Fabrizio, Richard Brill Jan 2013

Migratory And Within-Estuary Behaviors Of Adult Summer Flounder (Paralichthys Dentatus) In A Lagoon System Of The Southern Mid-Atlantic Bight, Karen M. Capossela, Mary C. Fabrizio, Richard Brill

VIMS Articles

We monitored the movements of 45 adult Summer Flounder (Paralichthys dentatus) between June 2007 and July 2008 through the use of passive acoustic telemetry to elucidate migratory and within-estuary behaviors in a lagoon system of the southern mid-Atlantic Bight. Between 8 June and 10 October 2007, fish resided primarily in the deeper (>3 m) regions of the system and exhibited low levels of large-scale (100s of meters) activity. Mean residence time within this estuarine lagoon system was conservatively estimated to be 130 days (range: 18-223 days), which is 1.5 times longer than the residence time previously reported for Summer ...


Microzooplankton Grazing Along The Western Antarctic Peninsula, Lm Garzio, Deborah K. Steinberg, M Erickson, Hw Ducklow Jan 2013

Microzooplankton Grazing Along The Western Antarctic Peninsula, Lm Garzio, Deborah K. Steinberg, M Erickson, Hw Ducklow

VIMS Articles

The significance of microzooplankton as grazers in pelagic ecosystems has been established, yet relatively few studies of microzooplankton grazing, compared to that of macrozooplankton, have been conducted in the Southern Ocean. We report phytoplankton and bacterial growth and grazing mortality rates along the Western Antarctic Peninsula (WAP), a region of rapid climate change. Growth and grazing rates were determined by dilution experiments at select stations along the WAP in January of 2009 to 2011 and in the nearshore waters near Palmer Station in February and March 2011. Microzooplankton exerted higher grazing pressure on bacteria compared to phytoplankton along the WAP ...


Extratropical Storm Inundation Testbed: Intermodel Comparisons In Scituate, Massachusetts, Changsheng Chen, Et Al., Harry V. Wang Jan 2013

Extratropical Storm Inundation Testbed: Intermodel Comparisons In Scituate, Massachusetts, Changsheng Chen, Et Al., Harry V. Wang

VIMS Articles

The Integrated Ocean Observing System Super-regional Coastal Modeling Testbed had one objective to evaluate the capabilities of three unstructured-grid fully current-wave coupled ocean models (ADCIRC/SWAN, FVCOM/SWAVE, SELFE/WWM) to simulate extratropical storm-induced inundation in the US northeast coastal region. Scituate Harbor (MA) was chosen as the extratropical storm testbed site, and model simulations were made for the 24-27 May 2005 and 17-20 April 2007 (Patriot's Day Storm) nor'easters. For the same unstructured mesh, meteorological forcing, and initial/boundary conditions, intermodel comparisons were made for tidal elevation, surface waves, sea surface elevation, coastal inundation, currents, and volume ...


Distribution And Sources Of Organic Matter In Surface Marine Sediments Across The North American Arctic Margin, Miguel A. Goni, Alison E. O'Connor, Zou Zou Kyzyk, Mark B. Yunker, Charles Gobeil, Robie W. Macdonald Jan 2013

Distribution And Sources Of Organic Matter In Surface Marine Sediments Across The North American Arctic Margin, Miguel A. Goni, Alison E. O'Connor, Zou Zou Kyzyk, Mark B. Yunker, Charles Gobeil, Robie W. Macdonald

VIMS Articles

As part of the International Polar Year research program, we conducted a survey of surface marine sediments from box cores along a section extending from the Bering Sea to Davis Strait via the Canadian Archipelago. We used bulk elemental and isotopic compositions, together with biomarkers and principal components analysis, to elucidate the distribution of marine and terrestrial organic matter in different regions of the North American Arctic margin. Marked regional contrasts were observed in organic carbon loadings, with the highest values (1 mg C m(-2) sediment) found in sites along Barrow Canyon and the Chukchi and Bering shelves, all ...


Photochemical And Microbial Alteration Of Dissolved Organic Matter In Temperate Headwater Streams Associated With Different Land Use, Yuehan Lu, James E. Bauer, Elizabeth A. Canuel, Youhei Yamashita, Randy Chambers, Rudolf Jaffe Jan 2013

Photochemical And Microbial Alteration Of Dissolved Organic Matter In Temperate Headwater Streams Associated With Different Land Use, Yuehan Lu, James E. Bauer, Elizabeth A. Canuel, Youhei Yamashita, Randy Chambers, Rudolf Jaffe

VIMS Articles

Photochemical and microbial transformations of DOM were evaluated in headwater streams draining forested and human-modified lands (pasture, cropland, and urban development) by laboratory incubations. Changes in DOC concentrations, DOC isotopic signatures, and DOM fluorescence properties were measured to assess the amounts, sources, ages, and properties of reactive and refractory DOM under the influence of photochemistry and/or bacteria. DOC in streams draining forest-dominated watersheds was more photoreactive than in streams draining mostly human-modified watersheds, possibly due to greater contributions of terrestrial plant-derived DOC and lower amounts of prior light exposure in forested streams. Overall, the percentage of photoreactive DOC in ...


Tidal Wind Mapping From Observations Of A Meteor Radar Chain In December 2011, You Yu, Weixing Wan, Baiqi Ning, Libo Liu, Zhengui Wang, Lianhuan Hu, Zhipeng Ren Jan 2013

Tidal Wind Mapping From Observations Of A Meteor Radar Chain In December 2011, You Yu, Weixing Wan, Baiqi Ning, Libo Liu, Zhengui Wang, Lianhuan Hu, Zhipeng Ren

VIMS Articles

This article proposes a technique to map the tidal winds in the mesosphere and lower thermosphere (MLT) region from the observations of a four-station meteor radar chain located at middle- and low-latitudes along the 120 degrees E meridian in the Northern Hemisphere. A 1month dataset of the horizontal winds in the altitude range of 80-100km is observed during December 2011. We first decompose the tidal winds into mean, diurnal, semidiurnal, and terdiurnal components for each station. It is found that the diurnal/semidiurnal components dominate at the low-latitude/midlatitude stations. Their amplitudes increase at lower altitudes and then decrease at ...


Modeling The Effect Of Hypoxia On Macrobenthos Production In The Lower Rappahannock River, Chesapeake Bay, Usa, Samuel Kersey Sturdivant, Mark Brush, Robert J. Diaz Jan 2013

Modeling The Effect Of Hypoxia On Macrobenthos Production In The Lower Rappahannock River, Chesapeake Bay, Usa, Samuel Kersey Sturdivant, Mark Brush, Robert J. Diaz

VIMS Articles

Hypoxia in Chesapeake Bay has substantially increased in recent decades, with detrimental effects on macrobenthic production; the production of these fauna link energy transfer from primary consumers to epibenthic and demersal predators. As such, the development of accurate predictive models that determine the impact of hypoxia on macrobenthic production is important. A continuous-time, biomass-based model was developed for the lower Rappahannock River, a Bay tributary prone to seasonal hypoxia. Phytoplankton, zooplankton, and macrobenthic state variables were modeled, with a focus on quantitatively constraining the effect of hypoxia on macrobenthic biomass. This was accomplished through regression with Z': a sigmoidal function ...


Comparative Visual Ecophysiology Of Mid-Atlantic Temperate Reef Fishes, Andrij Z. Horodysky, Richard Brill, Kendyl C. Crawford, Elizabeth S. Seagroves, Andrea K. Johnson Jan 2013

Comparative Visual Ecophysiology Of Mid-Atlantic Temperate Reef Fishes, Andrij Z. Horodysky, Richard Brill, Kendyl C. Crawford, Elizabeth S. Seagroves, Andrea K. Johnson

VIMS Articles

The absolute light sensitivities, temporal properties, and spectral sensitivities of the visual systems of three mid-Atlantic temperate reef fishes (Atlantic spadefish [Ephippidae: Chaetodipterus faber], tautog [Labridae: Tautoga onitis], and black sea bass [Serranidae: Centropristis striata]) were studied via electroretinography (ERG). Pelagic Atlantic spadefish exhibited higher temporal resolution but a narrower dynamic range than the two more demersal foragers. The higher luminous sensitivities of tautog and black sea bass were similar to other benthic and demersal coastal mid-Atlantic fishes. Flicker fusion frequency experiments revealed significant interspecific differences at maximum intensities that correlated with lifestyle and habitat. Spectral responses of the three ...


Age-Specific Responses To Spring Temperature In A Migratory Songbird: Older Females Attempt More Broods In Warmer Springs, L. Bulluck, S. Huber, C. Viverette, C. Blem Jan 2013

Age-Specific Responses To Spring Temperature In A Migratory Songbird: Older Females Attempt More Broods In Warmer Springs, L. Bulluck, S. Huber, C. Viverette, C. Blem

VIMS Articles

Increasing global temperature has led to an interest in plasticity in the timing of annual events; however, little is known about the demographic consequences of changing phenology. Annual reproductive success varies significantly among individuals within a population, and some of that variation has to do with the number of broods attempted by reproducing adults. In birds, female age and the timing of reproduction are often predictors of multiple breeding. We hypothesize that double brooding rates may be affected by spring temperature and that the response may vary with female age. We used a long-term reproductive data set for a migratory ...


Molecular And Functional Ecology Of Aquatic Microbial Symbionts, Hans-Peter Grossart, Lasse Riemann, Kam W. Tang Jan 2013

Molecular And Functional Ecology Of Aquatic Microbial Symbionts, Hans-Peter Grossart, Lasse Riemann, Kam W. Tang

VIMS Articles

No abstract provided.


Decline And Local Extinction Of Caribbean Eusocial Shrimp, J. Emmett Duffy, Kenneth S. Macdonald, Kristin M. Hultgren, Tin Chi Solomon Chak, Dustin Rubenstein Jan 2013

Decline And Local Extinction Of Caribbean Eusocial Shrimp, J. Emmett Duffy, Kenneth S. Macdonald, Kristin M. Hultgren, Tin Chi Solomon Chak, Dustin Rubenstein

VIMS Articles

The tropical shrimp genus Synalpheus includes the only eusocial marine animals. In much of the Caribbean, eusocial species have dominated the diverse fauna of sponge-dwelling shrimp in coral rubble for at least the past two decades. Here we document a recent, dramatic decline and apparent local extinction of eusocial shrimp species on the Belize Barrier Reef. Our collections from shallow reefs in central Belize in 2012 failed to locate three of the four eusocial species formerly abundant in the area, and showed steep declines in colony size and increases in frequency of queenless colonies prior to their disappearance. Concordant with ...


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, R J. Orth Jan 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, R J. Orth

VIMS Articles

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 ...


Age, Growth, And Reproductive Biology Of Cownose Rays In Chesapeake Bay, Robert A. Fisher, Garrett C. Call, R. Dean Grubbs Jan 2013

Age, Growth, And Reproductive Biology Of Cownose Rays In Chesapeake Bay, Robert A. Fisher, Garrett C. Call, R. Dean Grubbs

VIMS Articles

The Cownose Ray Rhinoptera bonasus is an opportunistic predator of benthic invertebrates and has had a long history of negative interactions with commercial shellfish industries. Most recently, Cownose Rays have been implicated in negatively affecting the recovery of bay scallop Argopecten irradians stocks in North Carolina and oyster restoration and commercial aquaculture efforts in Chesapeake Bay. A mitigation attempt to decrease predation on shellfish has resulted in an unregulated fishery for Cownose Rays. Cownose Ray life history suggests that they are highly susceptible to overexploitation. We determined age, growth, and size at maturity for Cownose Rays collected in Chesapeake Bay ...


Indication Of Density-Dependent Changes In Growth And Maturity Of The Barndoor Skate On Georges Bank, Karson Coutre, Todd Gedamke, David Rudders, William B. Driggers Iii, David M. Koester, James A. Sulikowski Jan 2013

Indication Of Density-Dependent Changes In Growth And Maturity Of The Barndoor Skate On Georges Bank, Karson Coutre, Todd Gedamke, David Rudders, William B. Driggers Iii, David M. Koester, James A. Sulikowski

VIMS Articles

Drastic increases or decreases in biomass often result in density-dependent changes in life history characteristics within a fish population. Acknowledging this phenomenon and in light of the recent biomass increase in Barndoor Skate Dipturus laevis, the current study re-evaluated the growth rate and sexual maturity of 244 specimens collected from 2009-2011within closed areas I and II on Georges Bank, USA. Ages were estimated using vertebral band counts from skate that ranged from 21 to 129cm TL. The von Bertalanffy growth function was applied to pooled age-at-length data. Parameter estimates from the current study of L = 155cm TL and k = 0 ...


Fluid Driven By Tangential Velocity And Shear Stress: Mathematical Analysis, Numerical Experiment, And Implication To Surface Flow, H. S. Tang, L. Z. Zhang, J. P. -Y. Maa, H. Li, C.B. Jiang, R. Hussain Jan 2013

Fluid Driven By Tangential Velocity And Shear Stress: Mathematical Analysis, Numerical Experiment, And Implication To Surface Flow, H. S. Tang, L. Z. Zhang, J. P. -Y. Maa, H. Li, C.B. Jiang, R. Hussain

VIMS Articles

This paper investigates behaviors of flows driven by tangential velocity and shear stress on their boundaries such as solid walls and water surfaces. In a steady flow between two parallel plates with one of them in motion, analytic solutions are the same when a velocity and a shear stress boundary condition are applied on the moving plate. For an unsteady, impulsively started flow, however, analysis shows that solutions for velocity profiles as well as energy transferring and dissipation are different under the two boundary conditions. In an air-water flow, if either a velocity or a stress condition is imposed at ...


The Maredat Global Database Of High Performance Liquid Chromatography Marine Pigment Measurements, J. Peloquin, Walker O. Smith Jr. Jan 2013

The Maredat Global Database Of High Performance Liquid Chromatography Marine Pigment Measurements, J. Peloquin, Walker O. Smith Jr.

VIMS Articles

A global pigment database consisting of 35 634 pigment suites measured by high performance liquid chromatography was assembled in support of the MARine Ecosytem DATa (MAREDAT) initiative. These data originate from 136 field surveys within the global ocean, were solicited from investigators and databases, compiled, and then quality controlled. Nearly one quarter of the data originates from the Laboratoire d'Oceanographie de Villefranche (LOV), with an additional 17% and 19% stemming from the US JGOFS and LTER programs, respectively. The MAREDAT pigment database provides high quality measurements of the major taxonomic pigments including chlorophylls a and b, 19'-butanoyloxyfucoxanthin, 19 ...


Longitudinal Variability Of Size-Fractionated N-2 Fixation And Don Release Rates Along 24.5 Degrees N In The Subtropical North Atlantic, Mar Benavides, Deborah A. Bronk, Nona S.R. Agawin, M. Dolores Perez-Hernandez, Alonso Hernandez-Guerra, Javier Aristegui Jan 2013

Longitudinal Variability Of Size-Fractionated N-2 Fixation And Don Release Rates Along 24.5 Degrees N In The Subtropical North Atlantic, Mar Benavides, Deborah A. Bronk, Nona S.R. Agawin, M. Dolores Perez-Hernandez, Alonso Hernandez-Guerra, Javier Aristegui

VIMS Articles

Dinitrogen (N-2) fixation and dissolved organic nitrogen (DON) release rates were measured on fractionated samples (>10 mu m and m) along 24.5 degrees N in the subtropical North Atlantic. Net N-2 fixation rates (N-2 assimilation into biomass) ranged from 0.01 to 0.4 nmol N L-1 h(-1), and DON release rates ranged from 0.001 to 0.09 nmol N L-1 h(-1). DON release represented approximate to 14% and approximate to 23% of >10 mu m and (assimilation into biomass plus DON release), respectively. This implies that by overlooking DON release, N-2 fixation rates are underestimated ...