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VIMS Articles

2017

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Articles 1 - 30 of 74

Full-Text Articles in Life Sciences

A Communal Catalogue Reveals Earth’S Multiscale Microbial Diversity, Luke R. Thompson, Jon G. Saunders, Et Al, Earth Microbiome Project Consortium, Donglai Gong Nov 2017

A Communal Catalogue Reveals Earth’S Multiscale Microbial Diversity, Luke R. Thompson, Jon G. Saunders, Et Al, Earth Microbiome Project Consortium, Donglai Gong

VIMS Articles

Our growing awareness of the microbial world's importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about microbial life on Earth. Here we present a meta-analysis of microbial community samples collected by hundreds of researchers for the Earth Microbiome Project. Coordinated protocols and new analytical methods, particularly the use of exact sequences instead of clustered operational taxonomic units, enable bacterial and archaeal ribosomal RNA gene sequences to be followed across ...


Performance Of A Low-Cost, Solar-Powered Pop-Up Satellite Archival Tag For Assessing Post-Release Mortality Of Atlantic Bluefin Tuna (Thunnus Thynnus) Caught In The Us East Coast Light-Tackle Recreational Fishery, William M. Goldsmith, Andrew M. Scheld, John Graves Nov 2017

Performance Of A Low-Cost, Solar-Powered Pop-Up Satellite Archival Tag For Assessing Post-Release Mortality Of Atlantic Bluefin Tuna (Thunnus Thynnus) Caught In The Us East Coast Light-Tackle Recreational Fishery, William M. Goldsmith, Andrew M. Scheld, John Graves

VIMS Articles

Pop-up satellite archival tags (PSATs) are a valuable tool for estimating mortality of pelagic fishes released from commercial and recreational fishing gears. However, the high cost of PSATs limits sample sizes, resulting in low-precision post-release mortality estimates with little management applicability. We evaluate the performance of a lower-cost PSAT designed to enable large-scale post-release mortality studies. The tag uses solar rather than battery power, does not include a depth sensor, and transmits daily summaries of light and temperature data rather than high-resolution habitat profiles, contributing to a substantially lower per-unit price. We assessed the tag’s ability to detect mortality ...


Identifying Critical Recruitment Bottlenecks Limiting Seedling Establishment In A Degraded Seagrass Ecosystem, J Statton, Lr Montoya, R J. Orth, Kw Dixon, Ga Kendrick Nov 2017

Identifying Critical Recruitment Bottlenecks Limiting Seedling Establishment In A Degraded Seagrass Ecosystem, J Statton, Lr Montoya, R J. Orth, Kw Dixon, Ga Kendrick

VIMS Articles

Identifying early life-stage transitions limiting seagrass recruitment could improve our ability to target demographic processes most responsive to management. Here we determine the magnitude of life-stage transitions along gradients in physical disturbance limiting seedling establishment for the marine angiosperm, Posidonia australis. Transition matrix models and sensitivity analyses were used to identify which transitions were critical for successful seedling establishment during the first year of seed recruitment and projection models were used to predict the most appropriate environments and seeding densities. Total survival probability of seedlings was low (0.001), however, transition probabilities between life-stages differed across the environmental gradients; seedling ...


Low Apparent Survival And Heterogeneous Movement Patterns Of Invasive Blue Catfish In A Coastal River, Troy D. Tuckey, Mary C. Fabrizio, Alicia J. Norris, Mary Groves Nov 2017

Low Apparent Survival And Heterogeneous Movement Patterns Of Invasive Blue Catfish In A Coastal River, Troy D. Tuckey, Mary C. Fabrizio, Alicia J. Norris, Mary Groves

VIMS Articles

Blue Catfish Ictalurus furcatus were purposefully introduced into freshwater tributaries to Chesapeake Bay in the past, and populations have subsequently spread to new areas, negatively impacting native communities and causing concern for resource managers. To aid development of management strategies, we implemented a multiyear (2012–2015) tagging study of invasive Blue Catfish in a 40-km stretch of the Potomac River to estimate survival and assess movement patterns. Blue Catfish (N = 1,237) were captured by electrofishing and double-tagged to allow us to estimate tag retention rates; we used reward tags to increase reporting rates. Recaptured fish (N = 104; 8.4 ...


Reef Height Drives Threshold Dynamics Of Restored Oyster Reefs, Allison M. Colden, Robert J. Latour, Rom Lipcius Nov 2017

Reef Height Drives Threshold Dynamics Of Restored Oyster Reefs, Allison M. Colden, Robert J. Latour, Rom Lipcius

VIMS Articles

Nonlinear threshold responses to biotic or abiotic forcing may produce multiple population trajectories dependent upon initial conditions, which can reinforce population recovery or drive local ex - tinction, yet experimental tests of this phenomenon are lacking in marine ecosystems. In field experiments at 4 sites in 2 tributaries of lower Chesapeake Bay, we examined demographic responses (density and survival) of eastern oyster Crassostrea virginica populations to reef height and associated gradients in sediment deposition and habitat complexity. After 2 yr, oyster reefs exhibited diverging trajectories to ward either degradation or persistence, dependent upon initial reef height. Reefs higher than 0.3 ...


Collection Techniques For The Analyses Of Pathogens In Crustaceans, Jeffrey D. Shields Nov 2017

Collection Techniques For The Analyses Of Pathogens In Crustaceans, Jeffrey D. Shields

VIMS Articles

Outbreaks of diseases have been reported from a number of ecologically or commercially important crustaceans in tropical, temperature, and boreal waters. The etiology of a disease is often unknown prior to these outbreaks and the effect of the pathogen on the host population is poorly understood. Various techniques can be used to collect, identify, and monitor host populations for pathogens. These include classical methods, such as visual or histological assessment, to more refined techniques, such as simple and quantitative polymerase chain reaction assays. The strengths and weaknesses of the different methods are presented as well as some general guidelines for ...


Bottom-Up Control Of Parasites, David S. Johnson, Richard Heard Oct 2017

Bottom-Up Control Of Parasites, David S. Johnson, Richard Heard

VIMS Articles

Parasitism is a fundamental ecological interaction. Yet we understand relatively little about the ecological role of parasites compared to the role of free-living organisms. Bottom-up theory predicts that resource enhancement will increase the abundance and biomass of free-living organisms. Similarly, parasite abundance and biomass should increase in an ecosystem with resource enhancement. We tested this hypothesis in a landscape-level experiment in which salt marshes (60,000 m2 each) received elevated nutrient concentrations via flooding tidal waters for 11 yr to mimic eutrophication. Nutrient enrichment elevated the densities of the talitrid amphipod, Orchestia grillus, and the density and biomass of its ...


Impact Of Disease On The Survival Of Three Commercially Fished Species, John M. Hoenig, Maya L. Groner, Matthew W. Smith, Wolfgang K. Vogelbein, David M. Taylor, Donald F. Landers, John T. Swenarton, David T. Gauthier, Philip W. Sadler, Mark A. Matsche, Ashley N. Haines, Hamish J. Small, Roger Pradel, Remi Choquet, Jeffrey D. Shields Oct 2017

Impact Of Disease On The Survival Of Three Commercially Fished Species, John M. Hoenig, Maya L. Groner, Matthew W. Smith, Wolfgang K. Vogelbein, David M. Taylor, Donald F. Landers, John T. Swenarton, David T. Gauthier, Philip W. Sadler, Mark A. Matsche, Ashley N. Haines, Hamish J. Small, Roger Pradel, Remi Choquet, Jeffrey D. Shields

VIMS Articles

Recent increases in emergent infectious diseases have raised concerns about the sustainability of some marine species. The complexity and expense of studying diseases in marine systems often dictate that conservation and management decisions are made without quantitative data on population-level impacts of disease. Mark-recapture is a powerful, underutilized, tool for calculating impacts of disease on population size and structure, even in the absence of etiological information. We applied logistic regression models to mark-recapture data to obtain estimates of disease-associated mortality rates in three commercially important marine species: snow crab (Chionoecetes opilio) in Newfoundland, Canada, that experience sporadic epizootics of bitter ...


Spatiotemporal Trends And Drivers Of Fish Condition In Chesapeake Bay, Robert J. Latour, James Gartland, Christopher F. Bonzek Sep 2017

Spatiotemporal Trends And Drivers Of Fish Condition In Chesapeake Bay, Robert J. Latour, James Gartland, Christopher F. Bonzek

VIMS Articles

Measures of condition in fishes are often used to assess the general well-being of fish populations since condition reflects the biotic and abiotic factors experienced by individuals over moderate time scales. Fish condition can also be used as an indicator of ecosystem suitability in the context of ecosystem-based management. From an ecosystem perspective, evaluation of fish condition is best described over multiple spatiotemporal scales and in a multi-species context. This study analyzed 14 yr (2002-2015) of fisheries-independent trawl survey data to evaluate trends in condition for 16 demersal fishes inhabiting Chesapeake Bay, the largest estuary in the USA. Seasonal and ...


Sea Level Rise May Increase Extinction Risk Of A Saltmarsh Ontogenetic Habitat Specialist, David S. Johnson, Bethany L. Williams Aug 2017

Sea Level Rise May Increase Extinction Risk Of A Saltmarsh Ontogenetic Habitat Specialist, David S. Johnson, Bethany L. Williams

VIMS Articles

Specialist species are more vulnerable to environmental change than generalist species. For species with ontogenetic niche shifts, specialization may occur at a particular life stage making those stages more susceptible to environmental change. In the salt marshes in the northeast U.S., accelerated sea level rise is shifting vegetation patterns from flood-intolerant species such as Spartina patens to the flood-tolerant Spartina alterniflora. We tested the potential impact of this change on the coffee bean snail, Melampus bidentatus, a numerically dominant benthic invertebrate with an ontogenetic niche shift. From a survey of eight marshes throughout the northeast U.S., small snails ...


Understanding Changes In Seagrass Communities, Sarah Nuss, Celeste Venolia Jul 2017

Understanding Changes In Seagrass Communities, Sarah Nuss, Celeste Venolia

VIMS Articles

Seagrass is an incredibly valuable habitat in the Chesapeake Bay. Students will use mock seagrass patches, modeled after a research transect along Goodwin Island, Virginia, to analyze change in seagrass percent cover during, and following, a major die-off event in 2010. Students also analyze water quality graphs from the same time period to help them determine why the die-off may have occurred.


Submersed Aquatic Vegetation In Chesapeake Bay: Sentinel Species In A Changing World, R J. Orth, William C. Dennison, Jonathan S. Lefcheck, Cassie Gurbisz, Michael Hannam, Jennifer Keisman, J. Brooke Landry, Ken Moore, Rebecca R. Murphy, Christopher J. Patrick, Jeremy Testa, Donald E. Weller, David J. Wilcox Jun 2017

Submersed Aquatic Vegetation In Chesapeake Bay: Sentinel Species In A Changing World, R J. Orth, William C. Dennison, Jonathan S. Lefcheck, Cassie Gurbisz, Michael Hannam, Jennifer Keisman, J. Brooke Landry, Ken Moore, Rebecca R. Murphy, Christopher J. Patrick, Jeremy Testa, Donald E. Weller, David J. Wilcox

VIMS Articles

Chesapeake Bay has undergone profound changes since European settlement. Increases in human and livestock populations, associated changes in land use, increases in nutrient loadings, shoreline armoring, and depletion of fish stocks have altered the important habitats within the Bay. Submersed aquatic vegetation (SAV) is a critical foundational habitat and provides numerous benefits and services to society. In Chesapeake Bay, SAV species are also indicators of environmental change because of their sensitivity to water quality and shoreline development. As such, SAV has been deeply integrated into regional regulations and annual assessments of management outcomes, restoration efforts, the scientific literature, and popular ...


History Of The Virginia Oyster Fishery, Chesapeake Bay, Usa, David M. Schulte May 2017

History Of The Virginia Oyster Fishery, Chesapeake Bay, Usa, David M. Schulte

VIMS Articles

Oyster populations in Virginia's waters of Chesapeake Bay were lightly exploited until the early 1800s, when industrial fishery vessels first arrived, driven south from New England due to the collapse of northeastern oyster fisheries. Early signs of overexploitation and habitat degradation were evident by the 1850s. The public fishery, where oyster fishers harvest on state-owned bottom, rapidly developed after the Civil War and peaked in the early 1880s. Declines were noted by the late 1880s and eventually prompted the creation of Virginia's shell-planting and oyster-seed (young-of-the-year, YOY) moving repletion program in the 1920s. Despite management and increasing repletion ...


Multifaceted Biodiversity Hotspots Of Marine Mammals For Conservation Priorities, Camille Albouy, Valentine L. Delattre, Bastien Merigot, Christine N. Meynard, Fabien Leprieur May 2017

Multifaceted Biodiversity Hotspots Of Marine Mammals For Conservation Priorities, Camille Albouy, Valentine L. Delattre, Bastien Merigot, Christine N. Meynard, Fabien Leprieur

VIMS Articles

Aim: Identifying the multifaceted biodiversity hotspots for marine mammals and their spatial overlap with human threats at the global scale.


Carbon Budget Of A Shallow, Lagoonal Estuary: Transformations And Source-Sink Dynamics Along The River-Estuary-Ocean Continuum, Jr Crosswell, Iris C. Anderson, Jw Stanhope, B Van Dam, Mark Brush, Et Al. Jan 2017

Carbon Budget Of A Shallow, Lagoonal Estuary: Transformations And Source-Sink Dynamics Along The River-Estuary-Ocean Continuum, Jr Crosswell, Iris C. Anderson, Jw Stanhope, B Van Dam, Mark Brush, Et Al.

VIMS Articles

A comprehensive carbon budget was constructed to quantify carbon flows through the freshwater-marine continuum of a temperate, microtidal estuary. We performed coordinated measurements of dissolved inorganic carbon and total organic carbon fluxes to resolve spatial variability between and along the channel and shoals and diel variability across the entire estuary for 2 yr. Net ecosystem metabolism (NEM) was the most significant control on carbon flow within estuary regions. However, metabolic rates were spatially coupled such that counteracting fluxes across the channel-shoal gradient or along the river-ocean gradient resulted in system-wide NEM that was closely in balance (-3.0 +/- 3.3 ...


Valuing Ecosystem Services: Oysters, Denitrification, And Nutrient Trading Programs, Gs Depiper, Dw Lipton, Rn Lipcius Jan 2017

Valuing Ecosystem Services: Oysters, Denitrification, And Nutrient Trading Programs, Gs Depiper, Dw Lipton, Rn Lipcius

VIMS Articles

As part of their strategy to meet total maximum daily load restrictions in the Chesapeake Bay, managers have developed nutrient trading markets to curb nitrogen and phosphorus flows into the estuarine system. Historically, nutrient trading programs have been restricted to credits between point sources or for agricultural mitigation technologies, such as the planting of cover crops. However, the denitrification and nutrient sequestration associated with oyster reefs has recently been a topic of much biological research. We investigate the role that nutrient credits for ecosystem services provided by restored oyster reefs can play in optimally managing oyster reef complexes by developing ...


Transmission Routes Maintaining A Viral Pathogen Of Steelhead Trout Within A Complex Multi-Host Assemblage, Rachel Breyta, Ilana Brito, Paige Ferguson, Gael Kurath, Kerry Naish, Maureen Purcell, Ar Wargo, Shannon Ladeau Jan 2017

Transmission Routes Maintaining A Viral Pathogen Of Steelhead Trout Within A Complex Multi-Host Assemblage, Rachel Breyta, Ilana Brito, Paige Ferguson, Gael Kurath, Kerry Naish, Maureen Purcell, Ar Wargo, Shannon Ladeau

VIMS Articles

This is the first comprehensive region wide, spatially explicit epidemiologic analysis of surveillance data of the aquatic viral pathogen infectious hematopoietic necrosis virus (IHNV) infecting native salmonid fish. The pathogen has been documented in the freshwater ecosystem of the Pacific Northwest of North America since the 1950s, and the current report describes the disease ecology of IHNV during 2000-2012. Prevalence of IHNV infection in monitored salmonid host cohorts ranged from 8% to 30%, with the highest levels observed in juvenile steelhead trout. The spatial distribution of all IHNV-infected cohorts was concentrated in two sub-regions of the study area, where historic ...


Redox Reactions And Weak Buffering Capacity Lead To Acidification In The Chesapeake Bay, Wei-Jun Cai, Wei-Jen Huang, George W. Luther Iii, Denis Pierrot, Ming Li, Jeremy Testa, Ming Xue, Andrew Joesoef, Roger L. Mann, Jean Brodeur, Yuan-Yuan Xu, Baoshan Chen, Najid Hussain, George G. Waldbusser, Jeffery Cornwell, W. Michael Kemp Jan 2017

Redox Reactions And Weak Buffering Capacity Lead To Acidification In The Chesapeake Bay, Wei-Jun Cai, Wei-Jen Huang, George W. Luther Iii, Denis Pierrot, Ming Li, Jeremy Testa, Ming Xue, Andrew Joesoef, Roger L. Mann, Jean Brodeur, Yuan-Yuan Xu, Baoshan Chen, Najid Hussain, George G. Waldbusser, Jeffery Cornwell, W. Michael Kemp

VIMS Articles

The combined effects of anthropogenic and biological CO2 inputs may lead to more rapid acidification in coastal waters compared to the open ocean. It is less clear, however, how redox reactions would contribute to acidification. Here we report estuarine acidification dynamics based on oxygen, hydrogen sulfide (H2S), pH, dissolved inorganic carbon and total alkalinity data from the Chesapeake Bay, where anthropogenic nutrient inputs have led to eutrophication, hypoxia and anoxia, and low pH. We show that a pH minimum occurs in mid-depths where acids are generated as a result of H2S oxidation in waters mixed upward from the anoxic depths ...


Human Indoor Exposure To Airborne Halogenated Flame Retardants: Influence Of Airborne Particle Size, M. J. La Guardia, Erika D. Schreder, Nancy Uding, Robert C. Hale Jan 2017

Human Indoor Exposure To Airborne Halogenated Flame Retardants: Influence Of Airborne Particle Size, M. J. La Guardia, Erika D. Schreder, Nancy Uding, Robert C. Hale

VIMS Articles

Inhalation of halogenated flame-retardants (HFRs) released from consumer products is an important route of exposure. However, not all airborne HFRs are respirable, and thus interact with vascular membranes within the gas exchange (alveolar) region of the lung. HFRs associated with large (> 4 mu m), inhalable airborne particulates are trapped on the mucosal lining of the respiratory tract and then are expelled or swallowed. The latter may contribute to internal exposure via desorption from particles in the digestive tract. Exposures may also be underestimated if personal activities that re-suspend particles into the breathing zone are not taken into account. Here, samples ...


Assessing The Impact Of Local And Regional Influences On Nitrogen Loads To Buzzards Bay, Ma, Shanna C. Williamson, Jennie E. Rheuban, Et Al Jan 2017

Assessing The Impact Of Local And Regional Influences On Nitrogen Loads To Buzzards Bay, Ma, Shanna C. Williamson, Jennie E. Rheuban, Et Al

VIMS Articles

Nitrogen and chlorophyll-a concentrations in estuarine systems often correlate positively with increased nitrogen input. To determine the interactions between nitrogen load, physical drivers, and water quality indicators, we estimated nitrogen inputs to 28 estuaries within the Buzzards Bay, Massachusetts (USA) watershed from 1985 to 2013. Estimates were derived by combining parcel specific wastewater disposal, point source wastewater discharge, land use, and atmospheric nitrogen deposition data with a previously verified nitrogen loading model. Linear regression analysis was used to quantify temporal trends in individual data sets and characterize relationships between variables. The land-use data indicated that fractional coverage of impervious surfaces ...


Forensic Reconstruction Of Ictalurus Punctatus Invasion Routes Using On-Line Fishermen Records, Filipe Banha, Ana Verissimo, Filipe Ribeiro, Anastacio Filipe Jan 2017

Forensic Reconstruction Of Ictalurus Punctatus Invasion Routes Using On-Line Fishermen Records, Filipe Banha, Ana Verissimo, Filipe Ribeiro, Anastacio Filipe

VIMS Articles

In this work, the presence of the channel catfish Ictalurus punctatus in the Portuguese section of the Guadiana drainage (Iberian Peninsula) is confirmed based on morphological and molecular species identification. The spatial and temporal dispersal of this non-native catfish was also reconstructed for the Guadiana drainage, based mostly on online fishermen records with minor contributions from the few scientific reports available. The obtained records (mainly from angling fora) span the period since the species' first reported presence in Iberia (1980s) up to the present, and support a westward invasion pattern of non-native fish (NNF) reported for the Iberian fish invasion ...


Denitrification Potential Of The Eastern Oyster Microbiome Using A 16s Rrna Gene Based Metabolic Inference Approach, Ann Arfken, Bk Song, Jeff S. Bowman, Michael Piehler Jan 2017

Denitrification Potential Of The Eastern Oyster Microbiome Using A 16s Rrna Gene Based Metabolic Inference Approach, Ann Arfken, Bk Song, Jeff S. Bowman, Michael Piehler

VIMS Articles

The eastern oyster (Crassostrea virginica) is a foundation species providing significant ecosystem services. However, the roles of oyster microbiomes have not been integrated into any of the services, particularly nitrogen removal through denitrification. We investigated the composition and denitrification potential of oyster microbiomes with an approach that combined 16S rRNA gene analysis, metabolic inference, qPCR of the nitrous oxide reductase gene (nosZ), and N-2 flux measurements. Microbiomes of the oyster digestive gland, the oyster shell, and sediments adjacent to the oyster reef were examined based on next generation sequencing (NGS) of 16S rRNA gene amplicons. Denitrification potentials of the microbiomes ...


Differential Effects Of Bivalves On Sediment Nitrogen Cycling In A Shallow Coastal Bay, Ashley Smyth, Anna E. Murphy, Iris C. Anderson, Bk Song Jan 2017

Differential Effects Of Bivalves On Sediment Nitrogen Cycling In A Shallow Coastal Bay, Ashley Smyth, Anna E. Murphy, Iris C. Anderson, Bk Song

VIMS Articles

In coastal ecosystems, suspension-feeding bivalves can remove nitrogen though uptake and assimilation or enhanced denitrification. Bivalves may also retain nitrogen through increased mineralization and dissimilatory nitrate reduction to ammonium (DNRA). This study investigated the effects of oyster reefs and clam aquaculture on denitrification, DNRA, and nutrient fluxes (NOx, NH4 6 +, O2). Core incubations were conducted seasonally on sediments adjacent to restored oyster reefs (Crassostrea virginica), clam aquaculture beds (Mercenaria mercenaria) which contained live clams, and bare sediments from Smith Island Bay, Virginia, USA. Denitrification was significantly higher at oyster reef sediments and clam aquaculture site than bare sediment in the ...


Oyster Toadfish (Opsanus Tau) Boatwhistle Call Detection And Patterns Within A Large-Scale Oyster Restoration Site, Shannon W. Ricci, Delwayne R. Bohnenstiehl, David B. Eggleston, M. Lisa Kellogg, R. Patrick Lyon Jan 2017

Oyster Toadfish (Opsanus Tau) Boatwhistle Call Detection And Patterns Within A Large-Scale Oyster Restoration Site, Shannon W. Ricci, Delwayne R. Bohnenstiehl, David B. Eggleston, M. Lisa Kellogg, R. Patrick Lyon

VIMS Articles

During May 2015, passive acoustic recorders were deployed at eight subtidal oyster reefs within Harris Creek Oyster Sanctuary in Chesapeake Bay, Maryland USA. These sites were selected to represent both restored and unrestored habitats having a range of oyster densities. Throughout the survey, the soundscape within Harris Creek was dominated by the boatwhistle calls of the oyster toadfish, Opsanus tau. A novel, multi-kernel spectral correlation approach was developed to automatically detect these boatwhistle calls using their two lowest harmonic bands. The results provided quantitative information on how call rate and call frequency varied in space and time. Toadfish boatwhistle fundamental ...


Vegetation Recovery In Tidal Marshes Reveals Critical Slowing Down Under Increased Inundation, Jim Van Belzen, Johan Van De Koppel, Matthew L. Kirwan, Daphne Van Der Wal, Peter M.J. Herman, Vasilis Dakos, Sonia Kefi, Marten Scheffer, Glenn R. Guntenspergen, Tjeerd J. Bouma Jan 2017

Vegetation Recovery In Tidal Marshes Reveals Critical Slowing Down Under Increased Inundation, Jim Van Belzen, Johan Van De Koppel, Matthew L. Kirwan, Daphne Van Der Wal, Peter M.J. Herman, Vasilis Dakos, Sonia Kefi, Marten Scheffer, Glenn R. Guntenspergen, Tjeerd J. Bouma

VIMS Articles

A declining rate of recovery following disturbance has been proposed as an important early warning for impending tipping points in complex systems. Despite extensive theoretical and laboratory studies, this 'critical slowing down' remains largely untested in the complex settings of real-world ecosystems. Here, we provide both observational and experimental support of critical slowing down along natural stress gradients in tidal marsh ecosystems. Time series of aerial images of European marsh development reveal a consistent lengthening of recovery time as inundation stress increases. We corroborate this finding with transplantation experiments in European and North American tidal marshes. In particular, our results ...


Microbial Community Response To Terrestrially Derived Dissolved Organic Matter In The Coastal Arctic, Re Sipler, Colleen T. E. Kellogg, Tara L. Connelly, Qn Roberts, Patricia L. Yager, Deborah A. Bronk Jan 2017

Microbial Community Response To Terrestrially Derived Dissolved Organic Matter In The Coastal Arctic, Re Sipler, Colleen T. E. Kellogg, Tara L. Connelly, Qn Roberts, Patricia L. Yager, Deborah A. Bronk

VIMS Articles

Warming at nearly twice the global rate, higher than average air temperatures are the new 'normal' for Arctic ecosystems. This rise in temperature has triggered hydrological and geochemical changes that increasingly release carbon-rich water into the coastal ocean via increased riverine discharge, coastal erosion, and the thawing of the semipermanent permafrost ubiquitous in the region. To determine the biogeochemical impacts of terrestrially derived dissolved organic matter (tDOM) on marine ecosystems we compared the nutrient stocks and bacterial communities present under ice-covered and ice-free conditions, assessed the lability of Arctic tDOM to coastal microbial communities from the Chukchi Sea, and identified ...


World Without Borders-Genetic Population Structure Of A Highly Migratory Marine Predator, The Blue Shark (Prionace Glauca), Ana Verssimo, Iris Sampaio, Jan Mcdowell, Paulo Alexandrino, Gonzalo Mucientes, Nuno Queiroz, Charlene Da Silva, Catherine S. Jones, Leslie R. Noble Jan 2017

World Without Borders-Genetic Population Structure Of A Highly Migratory Marine Predator, The Blue Shark (Prionace Glauca), Ana Verssimo, Iris Sampaio, Jan Mcdowell, Paulo Alexandrino, Gonzalo Mucientes, Nuno Queiroz, Charlene Da Silva, Catherine S. Jones, Leslie R. Noble

VIMS Articles

Highly migratory, cosmopolitan oceanic sharks often exhibit complex movement patterns influenced by ontogeny, reproduction, and feeding. These elusive species are particularly challenging to population genetic studies, as representative samples suitable for inferring genetic structure are difficult to obtain. Our study provides insights into the genetic population structure one of the most abundant and wide-ranging oceanic shark species, the blue shark Prionace glauca, by sampling the least mobile component of the populations, i.e., young-of-year and small juveniles (year; N = 348 individuals), at three reported nursery areas, namely, western Iberia, Azores, and South Africa. Samples were collected in two different time ...


Created Mangrove Wetlands Store Belowground Carbon And Surface Elevation Change Enables Them To Adjust To Sea-Level Rise, Ken W. Krauss, Nicole Cormier, Michael J. Osland, Matthew L. Kirwan, Camille L. Stagg, Janet A. Nestlerode, Marc J. Russell, Andrew S. From, Amanda C. Spivak, Darrin D. Dantin, James E. Harvey, Alejandro E. Almario Jan 2017

Created Mangrove Wetlands Store Belowground Carbon And Surface Elevation Change Enables Them To Adjust To Sea-Level Rise, Ken W. Krauss, Nicole Cormier, Michael J. Osland, Matthew L. Kirwan, Camille L. Stagg, Janet A. Nestlerode, Marc J. Russell, Andrew S. From, Amanda C. Spivak, Darrin D. Dantin, James E. Harvey, Alejandro E. Almario

VIMS Articles

Mangrove wetlands provide ecosystem services for millions of people, most prominently by providing storm protection, food and fodder. Mangrove wetlands are also valuable ecosystems for promoting carbon (C) sequestration and storage. However, loss of mangrove wetlands and these ecosystem services are a global concern, prompting the restoration and creation of mangrove wetlands as a potential solution. Here, we investigate soil surface elevation change, and its components, in created mangrove wetlands over a 25 year developmental gradient. All created mangrove wetlands were exceeding current relative sea-level rise rates (2.6 mm yr(-1)), with surface elevation change of 4.2-11.0 ...


Aquaculture Genomics, Genetics And Breeding In The United States: Current Status, Challenges, And Priorities For Future Research, Hisham Abdelrahman, Standish K. Allen Jr. Jan 2017

Aquaculture Genomics, Genetics And Breeding In The United States: Current Status, Challenges, And Priorities For Future Research, Hisham Abdelrahman, Standish K. Allen Jr.

VIMS Articles

Advancing the production efficiency and profitability of aquaculture is dependent upon the ability to utilize a diverse array of genetic resources. The ultimate goals of aquaculture genomics, genetics and breeding research are to enhance aquaculture production efficiency, sustainability, product quality, and profitability in support of the commercial sector and for the benefit of consumers. In order to achieve these goals, it is important to understand the genomic structure and organization of aquaculture species, and their genomic and phenomic variations, as well as the genetic basis of traits and their interrelationships. In addition, it is also important to understand the mechanisms ...


The Roles Of Resuspension, Diffusion And Biogeochemical Processes On Oxygen Dynamics Offshore Of The Rhone River, France: A Numerical Modeling Study, Julia Moriarty, Courtney K. Harris, Katja Fennel, Marjorie A.M. Friedrichs, Kehui Xu, Christophe Rabouille Jan 2017

The Roles Of Resuspension, Diffusion And Biogeochemical Processes On Oxygen Dynamics Offshore Of The Rhone River, France: A Numerical Modeling Study, Julia Moriarty, Courtney K. Harris, Katja Fennel, Marjorie A.M. Friedrichs, Kehui Xu, Christophe Rabouille

VIMS Articles

Observations indicate that resuspension and associated fluxes of organic material and porewater between the seabed and overlying water can alter biogeochemical dynamics in some environments, but measuring the role of sediment processes on oxygen and nutrient dynamics is challenging. A modeling approach offers a means of quantifying these fluxes for a range of conditions, but models have typically relied on simplifying assumptions regarding seabed-water-column interactions. Thus, to evaluate the role of resuspension on biogeochemical dynamics, we developed a coupled hydrodynamic, sediment transport, and biogeochemical model (HydroBioSed) within the Regional Ocean Modeling System (ROMS). This coupled model accounts for processes including ...