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Comparison Of Methods For Determining Biogeochemical Fluxes From A Restored Oyster Reef, Melanie Jackson, Michael S. Owens, Jeffrey C. Cornwell, M. Lisa Kellogg Dec 2018

Comparison Of Methods For Determining Biogeochemical Fluxes From A Restored Oyster Reef, Melanie Jackson, Michael S. Owens, Jeffrey C. Cornwell, M. Lisa Kellogg

VIMS Articles

Oyster reef restoration can significantly increase benthic denitrification rates. Methods applied to measure nutrient fluxes and denitrification from oyster reefs in previous studies include incubations of sediment cores collected adjacent to oyster clumps, benthic chambers filled with intact reef segments that have undergone in situ equilibration and ex situ incubation, and cores with single oysters. However, fluxes of nutrients vary by orders of magnitude among oyster reefs and methods. This study compares two methods of measuring nutrient and metabolic fluxes on restored oyster reefs: incubations including intact segments of oyster reef and incubations containing oyster clumps without underlying sediments. Fluxes ...


Restoring The Eastern Oyster: How Much Progress Has Been Made In 53 Years?, Ab Hernandez, Rd Brumbaugh, P Fredrick, R Grizzle, Mw Luckenbach, Ch Peterson, C Angelini Oct 2018

Restoring The Eastern Oyster: How Much Progress Has Been Made In 53 Years?, Ab Hernandez, Rd Brumbaugh, P Fredrick, R Grizzle, Mw Luckenbach, Ch Peterson, C Angelini

VIMS Articles

Coastal ecosystem restoration is accelerating globally as a means of enhancing shoreline protection, carbon storage, water quality, fisheries, and biodiversity. Among the most substantial of these efforts have been those focused on re-establishing oyster reefs across the US Atlantic and Gulf coasts. Despite considerable investment, it is unclear how the scale of and approaches toward oyster restoration have evolved. A synthesis of 1768 projects undertaken since 1964 reveals that oyster substrate restoration efforts have primarily been concentrated in the Chesapeake Bay and the Gulf Coast, have been heavily reliant on oyster shell, and have re-established 4.5% of the reef ...


Dermal Mycobacteriosis And Warming Sea Surface Temperatures Are Associated With Elevated Mortality Of Striped Bass In Chesapeake Bay, Maya L. Groner, John M. Hoenig, Roger Pradel, Remi Choquet, Wolfgang K. Vogelbein, David T. Gauthier, Marjorie A. M. Friedrichs Sep 2018

Dermal Mycobacteriosis And Warming Sea Surface Temperatures Are Associated With Elevated Mortality Of Striped Bass In Chesapeake Bay, Maya L. Groner, John M. Hoenig, Roger Pradel, Remi Choquet, Wolfgang K. Vogelbein, David T. Gauthier, Marjorie A. M. Friedrichs

VIMS Articles

Temperature is hypothesized to alter disease dynamics, particularly when species are living at or near their thermal limits. When disease occurs in marine systems, this can go undetected, particularly if the disease is chronic and progresses slowly. As a result, population-level impacts of diseases can be grossly underestimated. Complex migratory patterns, stochasticity in recruitment, and data and knowledge gaps can hinder collection and analysis of data on marine diseases. New tools enabling quantification of disease impacts in marine environments include coupled biogeochemical hydrodynamic models (to hindcast key environmental data), and multievent, multistate mark-recapture (MMSMR) (to quantify the effects of environmental ...


Human Influence At The Coast: Upland And Shoreline Stressors Affect Coastal Macrofauna And Are Mediated By Salinity, Rochelle D. Seitz, Kathleen E. Knick, Theresa M. Davenport, Gabrielle G. Saluta Aug 2018

Human Influence At The Coast: Upland And Shoreline Stressors Affect Coastal Macrofauna And Are Mediated By Salinity, Rochelle D. Seitz, Kathleen E. Knick, Theresa M. Davenport, Gabrielle G. Saluta

VIMS Articles

Anthropogenic stressors can affect subtidal communities within the land-water interface. Increasing anthropogenic activities, including upland and shoreline development, threaten ecologically important species in these habitats. In this study, we examined the consequences of anthropogenic stressors on benthic macrofaunal communities in 14 subestuaries of Chesapeake Bay. We investigated how subestuary upland use (forested, agricultural, developed land) and shoreline development (riprap and bulkhead compared to marsh and beach) affected density, biomass, and diversity of benthic infauna. Upland and shoreline development were parameters included in the most plausible models among a candidate set compared using corrected Akaike's Information Criterion. For benthic macrofauna ...


Mitotic Instability In Triploid And Tetraploid One-Year-Old Eastern Oyster, Crassostrea Virginica, Assessed By Cytogenetic And Flow Cytometry Techniques, Jt De Sousa, Sk Allen, Bm Wolfe, Jm Moss Feb 2018

Mitotic Instability In Triploid And Tetraploid One-Year-Old Eastern Oyster, Crassostrea Virginica, Assessed By Cytogenetic And Flow Cytometry Techniques, Jt De Sousa, Sk Allen, Bm Wolfe, Jm Moss

VIMS Articles

For commercial oyster aquaculture, triploidy has significant advantages. To produce triploids, the principal technology uses diploid x tetraploid crosses. The development of tetraploid brood stock for this purpose has been successful, but as more is understood about tetraploids, it seems clear that chromosome instability is a principal feature in oysters. This paper is a continuation of work to investigate chromosome instability in polyploid Crassostrea virginica. We established families between tetraploids-apparently stable (non-mosaic) and unstable (mosaic)-and normal reference diploids, creating triploid groups, as well as tetraploids between mosaic and non-mosaic tetraploids. Chromosome loss was about the same for triploid juveniles ...


Long-Term Nutrient Reductions Lead To The Unprecedented Recovery Of A Temperate Coastal Region, Js Lefcheck, Rj Orth, Wc Dennison, Dj Wilcox, Rr Murphy, Ka Moore, Et Al. Jan 2018

Long-Term Nutrient Reductions Lead To The Unprecedented Recovery Of A Temperate Coastal Region, Js Lefcheck, Rj Orth, Wc Dennison, Dj Wilcox, Rr Murphy, Ka Moore, Et Al.

VIMS Articles

Humans strongly impact the dynamics of coastal systems, yet surprisingly few studies mechanistically link management of anthropogenic stressors and successful restoration of nearshore habitats over large spatial and temporal scales. Such examples are sorely needed to ensure the success of ecosystem restoration efforts worldwide. Here, we unite 30 consecutive years of watershed modeling, biogeochemical data, and comprehensive aerial surveys of Chesapeake Bay, United States to quantify the cascading effects of anthropogenic impacts on submersed aquatic vegetation (SAV), an ecologically and economically valuable habitat. We employ structural equation models to link land use change to higher nutrient loads, which in turn ...


Wetlands In A Changing Climate: Science, Policy And Management, Wr Moomaw, Gl Chmura, Gt Davies, Cm Finlayson, Ba Middleton, Sm Natali, Je Perry, N Roulet, Ar Sutton-Grier Jan 2018

Wetlands In A Changing Climate: Science, Policy And Management, Wr Moomaw, Gl Chmura, Gt Davies, Cm Finlayson, Ba Middleton, Sm Natali, Je Perry, N Roulet, Ar Sutton-Grier

VIMS Articles

Part 1 of this review synthesizes recent research on status and climate vulnerability of freshwater and saltwater wetlands, and their contribution to addressing climate change (carbon cycle, adaptation, resilience). Peatlands and vegetated coastal wetlands are among the most carbon rich sinks on the planet sequestering approximately as much carbon as do global forest ecosystems. Estimates of the consequences of rising temperature on current wetland carbon storage and future carbon sequestration potential are summarized. We also demonstrate the need to prevent drying of wetlands and thawing of permafrost by disturbances and rising temperatures to protect wetland carbon stores and climate adaptation ...


Habitat Complexity And Benthic Predator-Prey Interactions In Chesapeake Bay, Cn Glaspie, Rd Seitz Jan 2018

Habitat Complexity And Benthic Predator-Prey Interactions In Chesapeake Bay, Cn Glaspie, Rd Seitz

VIMS Articles

In Chesapeake Bay, the soft-shell clam Mya arenaria (thin-shelled, deep-burrowing) exhibits population declines when predators are active, and it persists at low densities. In contrast, the hard clam Mercenaria mercenaria (thick-shelled, shallow-burrowing) has a stable population and age distribution. We examined the potential for habitat and predators to control densities and distributions of bivalves in a field caging experiment (Mya only) and laboratory mesocosm experiments (both species). In the field, clams exposed to predators experienced 76.3% greater mortality as compared to caged individuals, and blue crabs were likely responsible for most of the mortality of juvenile Mya. In mesocosm ...


Saltmarsh Plants, But Not Fertilizer, Facilitate Invertebrate Recolonization After An Oil Spill, Ds Johnson, Jw Fleeger, Mr Riggio, Ia Mendelssohn, Qx Lin, Dr Deis, A Hou Jan 2018

Saltmarsh Plants, But Not Fertilizer, Facilitate Invertebrate Recolonization After An Oil Spill, Ds Johnson, Jw Fleeger, Mr Riggio, Ia Mendelssohn, Qx Lin, Dr Deis, A Hou

VIMS Articles

Foundation species contribute to the recovery of animal communities from disturbance by engineering, by improving habitat quality, and by regulating food availability. In a salt marsh impacted by the Deepwater Horizon oil spill, we tested the hypothesis that nutrient subsidies would enhance the positive effects of the foundation species Spartina alterniflora on the initial recolonization of benthic invertebrate communities (e.g., copepods, annelids, nematodes) by augmenting food (i.e., microalgae) availability. After two months, plantings of S.alterniflora significantly elevated the densities of the polychaete Capitella capitata, meiofauna-sized annelids, and total macroinfauna over unplanted plots. After 7months, the significant effect ...


Antibiotic Effects On Microbial Communities Responsible For Denitrification And N2o Production In Grassland Soils, M Semedo, B Song, T Sparrer, Rl Phillips Jan 2018

Antibiotic Effects On Microbial Communities Responsible For Denitrification And N2o Production In Grassland Soils, M Semedo, B Song, T Sparrer, Rl Phillips

VIMS Articles

Antibiotics in soils may affect the structure and function of microbial communities. In this study, we investigated the acute effects of tetracycline on soil microbial community composition and production of nitrous oxide (N2O) and dinitrogen (N-2) as the end-products of denitrification. Grassland soils were pre-incubated with and without tetracycline for 1-week prior to measurements of N2O and N-2 production in soil slurries along with the analysis of prokaryotic and fungal communities by quantitative polymerase chain reaction (qPCR) and next-generation sequencing. Abundance and taxonomic composition of bacteria carrying two genotypes of N2O reductase genes (nosZ-I and nosZ-II) were evaluated through qPCR ...


Biotime: A Database Of Biodiversity Time Series For The Anthropocene, M Dornelas, Lh Antao, F Moyes, Ae Bates, Ae Magurran, Et Al., Jonathan S. Lefcheck Jan 2018

Biotime: A Database Of Biodiversity Time Series For The Anthropocene, M Dornelas, Lh Antao, F Moyes, Ae Bates, Ae Magurran, Et Al., Jonathan S. Lefcheck

VIMS Articles

Motivation: The BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community-led open-source database of biodiversity time series. Our goal is to accelerate and facilitate quantitative analysis of temporal patterns of biodiversity in the Anthropocene. Main types of variables included: The database contains 8,777,413 species abundance records, from assemblages consistently sampled for a minimum of 2 years, which need not necessarily be consecutive. In addition, the ...


Estimating Fishing And Natural Mortality Rates, And Catchability Coefficient, From A Series Of Observations On Mean Length And Fishing Effort, Ay Then, Jm Hoenig, Qc Huynh Jan 2018

Estimating Fishing And Natural Mortality Rates, And Catchability Coefficient, From A Series Of Observations On Mean Length And Fishing Effort, Ay Then, Jm Hoenig, Qc Huynh

VIMS Articles

Gedamke and Hoenig (2006) (Transactions of the American Fisheries Society, 135: 476-487) developed a non-equilibrium version of the Beverton and Holt estimator of total mortality rate, Z, based on mean length and thereby increased the usefulness of length-based methods. In this study, we extend their model by replacing period-specific Z parameters with the year-specific parameterization Z(y) = qf(y) + M where q is the catchability coefficient, f(y) is the fishing effort in year y, F (= qf) is the fishing mortality rate, and M is the natural mortality rate. Thus, the problem reduces to estimating just three parameters: q, M ...


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 ...


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 ...


Abundance And Local-Scale Processes Contribute To Multi-Phyla Gradients In Global Marine Diversity, Gj Edgar, Tj Alexander, Js Lefcheck, Ae Bates, Sj Kininmonth, Et Al. Jan 2017

Abundance And Local-Scale Processes Contribute To Multi-Phyla Gradients In Global Marine Diversity, Gj Edgar, Tj Alexander, Js Lefcheck, Ae Bates, Sj Kininmonth, Et Al.

VIMS Articles

Among themost enduring ecological challenges is an integrated theory explaining the latitudinal biodiversity gradient, including discrepancies observed at different spatial scales. Analysis of Reef Life Survey data for 4127 marine species at 2406 coral and rocky sites worldwide confirms that the total ecoregion richness peaks in low latitudes, near +15 degrees N and -15 degrees S. However, although richness at survey sites is maximal near the equator for vertebrates, it peaks at high latitudes for large mobile invertebrates. Site richness for different groups is dependent on abundance, which is in turn correlated with temperature for fishes and nutrients for macroinvertebrates ...


Lipid Consumption In Coral Larvae Differs Among Sites: A Consideration Of Environmental History In A Global Ocean Change Scenario, Eb Rivest, Cs Chen, Ty Fan, Hh Li, Ge Hofmann Jan 2017

Lipid Consumption In Coral Larvae Differs Among Sites: A Consideration Of Environmental History In A Global Ocean Change Scenario, Eb Rivest, Cs Chen, Ty Fan, Hh Li, Ge Hofmann

VIMS Articles

The success of early life-history stages is an environmentally sensitive bottleneck for many marine invertebrates. Responses of larvae to environmental stress may vary due to differences in maternal investment of energy stores and acclimatization/adaptation of a population to local environmental conditions. In this study, we compared two populations from sites with different environmental regimes (Moorea and Taiwan). We assessed the responses of Pocillopora damicornis larvae to two future co-occurring environmental stressors: elevated temperature and ocean acidification. Larvae from Taiwan were more sensitive to temperature, producing fewer energy-storage lipids under high temperature. In general, planulae in Moorea and Taiwan responded ...


Spatio-Temporal Development Of Vegetation Die-Off In A Submerging Coastal Marsh, L Schepers, M Kirwan, G Guntenspergen, S Temmerman Jan 2017

Spatio-Temporal Development Of Vegetation Die-Off In A Submerging Coastal Marsh, L Schepers, M Kirwan, G Guntenspergen, S Temmerman

VIMS Articles

In several places around the world, coastal marsh vegetation is converting to open water through the formation of pools. This is concerning, as vegetation die-off is expected to reduce the marshes' capacity to adapt to sea level rise by vegetation-induced sediment accretion. Quantitative analyses of the spatial and temporal development of marsh vegetation die-off are scarce, although these are needed to understand the bio-geomorphic feedback effects of vegetation die-off on flow, erosion, and sedimentation. In this study, we quantified the spatial and temporal development of marsh vegetation die-off with aerial images from 1938 to 2010 in a submerging coastal marsh ...


Asynchrony Among Local Communities Stabilises Ecosystem Function Of Metacommunities, Kr Wilcox, At Tredennick, Se Koerner, E Grman, Lm Hallett, Ds Johnson, Et Al. Jan 2017

Asynchrony Among Local Communities Stabilises Ecosystem Function Of Metacommunities, Kr Wilcox, At Tredennick, Se Koerner, E Grman, Lm Hallett, Ds Johnson, Et Al.

VIMS Articles

Temporal stability of ecosystem functioning increases the predictability and reliability of ecosystem services, and understanding the drivers of stability across spatial scales is important for land management and policy decisions. We used species-level abundance data from 62 plant communities across five continents to assess mechanisms of temporal stability across spatial scales. We assessed how asynchrony (i.e. different units responding dissimilarly through time) of species and local communities stabilised metacommunity ecosystem function. Asynchrony of species increased stability of local communities, and asynchrony among local communities enhanced metacommunity stability by a wide range of magnitudes (1-315%); this range was positively correlated ...


Linking The Abundance Of Estuarine Fish And Crustaceans In Nearshore Waters To Shoreline Hardening And Land Cover, Ms Kornis, D Breitburg, R Balouskus, Dm Bilkovic, La Davias, Rd Seitz, Et Al. Jan 2017

Linking The Abundance Of Estuarine Fish And Crustaceans In Nearshore Waters To Shoreline Hardening And Land Cover, Ms Kornis, D Breitburg, R Balouskus, Dm Bilkovic, La Davias, Rd Seitz, Et Al.

VIMS Articles

Human alteration of land cover (e.g., urban and agricultural land use) and shoreline hardening (e.g., bulkheading and rip rap revetment) are intensifying due to increasing human populations and sea level rise. Fishes and crustaceans that are ecologically and economically valuable to coastal systems may be affected by these changes, but direct links between these stressors and faunal populations have been elusive at large spatial scales. We examined nearshore abundance patterns of 15 common taxa across gradients of urban and agricultural land cover as well as wetland and hardened shoreline in tributary subestuaries of the Chesapeake Bay and Delaware ...


Carbon Budget Of A Shallow, Lagoonal Estuary: Transformations And Source-Sink Dynamics Along The River-Estuary-Ocean Continuum, Jr Crosswell, Ic Anderson, Jw Stanhope, B Van Dam, Mj 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, Ic Anderson, Jw Stanhope, B Van Dam, Mj 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 ...


Tropical Dead Zones And Mass Mortalities On Coral Reefs, Ah Altieri, Sb Harrison, J Seemann, R Collin, Rj Diaz, N Knowlton Jan 2017

Tropical Dead Zones And Mass Mortalities On Coral Reefs, Ah Altieri, Sb Harrison, J Seemann, R Collin, Rj Diaz, N Knowlton

VIMS Articles

Degradation of coastal water quality in the form of low dissolved oxygen levels (hypoxia) can harm biodiversity, ecosystem function, and human wellbeing. Extreme hypoxic conditions along the coast, leading to what are often referred to as "dead zones," are known primarily from temperate regions. However, little is known about the potential threat of hypoxia in the tropics, even though the known risk factors, including eutrophication and elevated temperatures, are common. Here we document an unprecedented hypoxic event on the Caribbean coast of Panama and assess the risk of dead zones to coral reefs worldwide. The event caused coral bleaching and ...


Ghost Of Invasion Past: Legacy Effects On Community Disassembly Following Eradication Of An Invasive Ecosystem Engineer, Pl Reynolds, J Glanz, S Yang, C Hann, J Couture, E Grosholz Jan 2017

Ghost Of Invasion Past: Legacy Effects On Community Disassembly Following Eradication Of An Invasive Ecosystem Engineer, Pl Reynolds, J Glanz, S Yang, C Hann, J Couture, E Grosholz

VIMS Articles

By changing ecosystem processes and altering the physical landscape, invasive ecosystem engineers can have substantial impacts on ecosystem functions and human economies and may facilitate other non-native species. Eradication programs in terrestrial and aquatic systems aim to reverse the impacts of invasive species and return the system to its pre-invasion conditions. Despite an extensive focus on the impacts of both native and non-native ecosystem engineers, the consequences of removing invasive ecosystem engineers, particularly in coastal ecosystems, are largely unknown. In this study, we quantified changes in a benthic community following the eradication of the invasive ecosystem engineer, hybrid cordgrass Spartina ...


Consumer Versus Resource Control And The Importance Of Habitat Heterogeneity For Estuarine Bivalves, Rd Seitz, Rn Lipcius, Ah Hines Jan 2017

Consumer Versus Resource Control And The Importance Of Habitat Heterogeneity For Estuarine Bivalves, Rd Seitz, Rn Lipcius, Ah Hines

VIMS Articles

The relative influence of consumers (top down) and resources (bottom up) on the distribution and abundance of organisms remains a key question in ecology. We examined the relationships between consumer and resource variables along a productivity gradient for a dominant predator-prey interaction in a marine soft-sediment system. We 1) quantified density and size of the clam Macoma balthica (prey species) in six replicate sites at each of four habitat types (shallow mud, deep mud, muddy sand and detrital mud) in the Rhode River, Chesapeake Bay. We selected one habitat type of high food availability and clam density (shallow mud) and ...


Shelled Pteropods In Peril: Assessing Vulnerability In A High Co2 Ocean, C Manno, N Bednarsek, Ga Tarling, Vl Peck, S Comeau, Patricia S. Thibodeau, Et Al. Jan 2017

Shelled Pteropods In Peril: Assessing Vulnerability In A High Co2 Ocean, C Manno, N Bednarsek, Ga Tarling, Vl Peck, S Comeau, Patricia S. Thibodeau, Et Al.

VIMS Articles

The impact of anthropogenic ocean acidification (OA) on marine ecosystems is a vital concern facing marine scientists and managers of ocean resources. Euthecosomatous pteropods (holoplanktonic gastropods) represent an excellent sentinel for indicating exposure to anthropogenic OA because of the sensitivity of their aragonite shells to the OA conditions less favorable for calcification. However, an integration of observations, experiments and modelling efforts is needed to make accurate predictions of how these organisms will respond to future changes to their environment. Our understanding of the underlying organismal biology and life history is far from complete and must be improved if we are ...


Saltmarsh Plant Responses To Eutrophication, Ds Johnson, Rs Warren, La Deegan, Tj Mozdzer Jan 2016

Saltmarsh Plant Responses To Eutrophication, Ds Johnson, Rs Warren, La Deegan, Tj Mozdzer

VIMS Articles

In saltmarsh plant communities, bottom-up pressure from nutrient enrichment is predicted to increase productivity, alter community structure, decrease biodiversity, and alter ecosystem functioning. Previous work supporting these predictions has been based largely on short-term, plot-level (e.g., 1-300 m(2)) studies, which may miss landscape-level phenomena that drive ecosystem-level responses. We implemented an ecosystem-scale, nine-year nutrient experiment to examine how saltmarsh plants respond to simulated conditions of coastal eutrophication. Our study differed from previous saltmarsh enrichment studies in that we applied realistic concentrations of nitrate (70-100 mu M NO3-), the most common form of coastal nutrient enrichment, via tidal water ...


Marine Phytophthora Species Can Hamper Conservation And Restoration Of Vegetated Coastal Ecosystems, Ll Govers, Wam In 'T Veid, Jp Meffert, Tj Bouma, Pcj Van Rijswick, Jht Heusinkveld, Rj Orth, Mm Van Katwijk, T Van Der Heide Jan 2016

Marine Phytophthora Species Can Hamper Conservation And Restoration Of Vegetated Coastal Ecosystems, Ll Govers, Wam In 'T Veid, Jp Meffert, Tj Bouma, Pcj Van Rijswick, Jht Heusinkveld, Rj Orth, Mm Van Katwijk, T Van Der Heide

VIMS Articles

Phytophthora species are potent pathogens that can devastate terrestrial plants, causing billions of dollars of damage yearly to agricultural crops and harming fragile ecosystems worldwide. Yet, virtually nothing is known about the distribution and pathogenicity of their marine relatives. This is surprising, as marine plants form vital habitats in coastal zones worldwide (i.e. mangrove forests, salt marshes, seagrass beds), and disease may be an important bottleneck for the conservation and restoration of these rapidly declining ecosystems. We are the first to report on widespread infection of Phytophthora and Halophytophthora species on a common seagrass species, Zostera marina (eelgrass), across ...


Salp Contributions To Vertical Carbon Flux In The Sargasso Sea, Jp Stone, Dk Steinberg Jan 2016

Salp Contributions To Vertical Carbon Flux In The Sargasso Sea, Jp Stone, Dk Steinberg

VIMS Articles

We developed a one-dimensional model to estimate salp contributions to vertical carbon flux at the Bermuda Atlantic Time-series Study (BATS) site in the North Atlantic subtropical gyre for a 17-yr period (April 1994 to December 2011). We based the model parameters on published rates of salp physiology and experimentally determined sinking and decomposition rates of salp carcasses. Salp grazing was low during non-bloom conditions, but routinely exceeded 100% of chlorophyll standing stock and primary production during blooms. Fecal pellet production was the largest source of salp carbon flux (78% of total), followed by respiration below 200 m (19%), sinking of ...


Spatial And Temporal Dynamics Of Atlantic Menhaden (Brevoortia Tyrannus) Recruitment In The Northwest Atlantic Ocean, A Buchheister, Tj Miller, Ed Houde, Dh Secor, Rj Latour Jan 2016

Spatial And Temporal Dynamics Of Atlantic Menhaden (Brevoortia Tyrannus) Recruitment In The Northwest Atlantic Ocean, A Buchheister, Tj Miller, Ed Houde, Dh Secor, Rj Latour

VIMS Articles

Atlantic menhaden, Brevoortia tyrannus, is an abundant, schooling pelagic fish that is widely distributed in the coastal Northwest Atlantic. It supports the largest single-species fishery by volume on the east coast of the United States. However, relatively little is known about factors that control recruitment, and its stock- recruitment relationship is poorly defined. Atlantic menhaden is managed as a single unit stock, but fisheries and environmental variables likely act regionally on recruitments. To better understand spatial and temporal variability in recruitment, fishery-independent time-series (1959-2013) of young-of-year (YOY) abundance indices from the Mid-Atlantic to Southern New England (SNE) were analysed using ...


Progress And Challenges In Coupled Hydrodynamic-Ecological Estuarine Modeling, Nk Ganju, Mj Brush, B Rashleigh, Al Aretxabaleta, P Del Barrio, Js Grear, La Harris, Sj Lake, Et Al. Jan 2016

Progress And Challenges In Coupled Hydrodynamic-Ecological Estuarine Modeling, Nk Ganju, Mj Brush, B Rashleigh, Al Aretxabaleta, P Del Barrio, Js Grear, La Harris, Sj Lake, Et Al.

VIMS Articles

Numerical modeling has emerged over the last several decades as a widely accepted tool for investigations in environmental sciences. In estuarine research, hydrodynamic and ecological models have moved along parallel tracks with regard to complexity, refinement, computational power, and incorporation of uncertainty. Coupled hydrodynamic-ecological models have been used to assess ecosystem processes and interactions, simulate future scenarios, and evaluate remedial actions in response to eutrophication, habitat loss, and freshwater diversion. The need to couple hydrodynamic and ecological models to address research and management questions is clear because dynamic feedbacks between biotic and physical processes are critical interactions within ecosystems. In ...


Fungal Denitrification: Bipolaris Sorokiniana Exclusively Denitrifies Inorganic Nitrogen In The Presence And Absence Of Oxygen, R Phillips, G Grelet, A Mcmillan, B Song, B Weir, Et Al. Jan 2016

Fungal Denitrification: Bipolaris Sorokiniana Exclusively Denitrifies Inorganic Nitrogen In The Presence And Absence Of Oxygen, R Phillips, G Grelet, A Mcmillan, B Song, B Weir, Et Al.

VIMS Articles

Fungi may play an important role in the production of the greenhouse gas nitrous oxide (N2O). Bipolaris sorokiniana is a ubiquitous saprobe found in soils worldwide, yet denitrification by this fungal strain has not previously been reported. We aimed to test if B. sorokiniana would produce N2O and CO2 in the presence of organic and inorganic forms of nitrogen (N) under microaerobic and anaerobic conditions. Nitrogen source (organic-N, inorganic-N, no-N control) significantly affected N2O and CO2 production both in the presence and absence of oxygen, which contrasts with bacterial denitrification. Inorganic N addition increased denitrification of N2O (from 0 to ...