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Full-Text Articles in Life Sciences
Accelerating Tropicalization And The Transformation Of Temperate Seagrass Meadows, Glenn A. Hyndes, Kenneth L. Heck Jr., Et Al, R J. Orth
Accelerating Tropicalization And The Transformation Of Temperate Seagrass Meadows, Glenn A. Hyndes, Kenneth L. Heck Jr., Et Al, R J. Orth
VIMS Articles
Climate-driven changes are altering production and functioning of biotic assemblages in terrestrial and aquatic environments. In temperate coastal waters, rising sea temperatures, warm water anomalies and poleward shifts in the distribution of tropical herbivores have had a detrimental effect on algal forests. We develop generalized scenarios of this form of tropicalization and its potential effects on the structure and functioning of globally significant and threatened seagrass ecosystems, through poleward shifts in tropical seagrasses and herbivores. Initially, we expect tropical herbivorous fishes to establish in temperate seagrass meadows, followed later by megafauna. Tropical seagrasses are likely to establish later, delayed by …
Microbial Nitrogen Processing In Hard Clam (Mercenaria Mercenaria) Aquaculture Sediments: The Relative Importance Of Denitrification And Dissimilatory Nitrate Reduction To Ammonium (Dnra), Ae Murphy, Iris C. Anderson, Ar Smyth, Bk Song, Mark Luckenbach
Microbial Nitrogen Processing In Hard Clam (Mercenaria Mercenaria) Aquaculture Sediments: The Relative Importance Of Denitrification And Dissimilatory Nitrate Reduction To Ammonium (Dnra), Ae Murphy, Iris C. Anderson, Ar Smyth, Bk Song, Mark Luckenbach
VIMS Articles
As bivalve aquaculture expands worldwide, an understanding of its role in nutrient cycling is necessary to ensure ecological sustainability and determine the potential of using bivalves for nutrient mitigation. Whereas several studies, primarily of epifaunal bivalves, have assessed denitrification, few have considered nutrient regeneration processes such as dissimilatory nitrate reduction to ammonium (DNRA), which competes with denitrification for nitrate and results in nitrogen retention rather than loss. This study compares sediment nitrogen cycling including mineralization, DNRA, and denitrification within U.S. clam aquaculture sediments to nearby uncultivated sediments, seasonally. Clam aquaculture significantly increased sediment ammonium and phosphate effluxes relative to uncultivated …
Nitrogen Sources And Net Growth Efficiency Of Zooplankton In Three Amazon River Plume Food Webs, Natalie Loick-Wilde, Sarah C. Weber, Brandon J. Condon, Douglas G. Capone, Victoria J. Coles, Patricia M. Medeiros, Deborah K. Steinberg, Joseph P. Montoya
Nitrogen Sources And Net Growth Efficiency Of Zooplankton In Three Amazon River Plume Food Webs, Natalie Loick-Wilde, Sarah C. Weber, Brandon J. Condon, Douglas G. Capone, Victoria J. Coles, Patricia M. Medeiros, Deborah K. Steinberg, Joseph P. Montoya
VIMS Articles
The plasticity of nitrogen specific net growth efficiency (NGE) in marine mesozooplankton is currently unresolved, with discordant lines of evidence suggesting that NGE is constant, or that it varies with nitrogen source, food availability, and food quality in marine ecosystems. Specifically, the fate of nitrogen from nitrogen fixation is poorly known. We use 15N : 14N ratios in plankton in combination with hydrological data, nutrient profiles, and nitrogen fixation rate measurements to investigate the relationship between new nitrogen sources and the nitrogen specific NGE in three plankton communities along the outer Amazon River plume. The NGE of small …
Foundation Species Identity And Trophic Complexity Affect Experimental Seagrass Communities, Althea F. P. Moore, J. Emmett Duffy
Foundation Species Identity And Trophic Complexity Affect Experimental Seagrass Communities, Althea F. P. Moore, J. Emmett Duffy
VIMS Articles
The abundance and species composition of marine foundation species is changing due to range expansion or contraction, with potentially important ecosystem-level consequences. In Chesapeake Bay, USA, warming is likely to favor the more heat and stress-tolerant Ruppia maritima (widgeongrass) over Zostera marina (eelgrass). Because of the key role of seagrasses in providing habitat and trophic support, it is important to determine whether the more stress-tolerant seagrass provides similar ecological functions to the species it may replace. We addressed how trophic control differs between communities associated with the 2 seagrass species in a mesocosm experiment. Grazing of epiphytic algae can benefit …
Out Of The Tower And Into The Classroom Or How Classroom Partnerships Give Marine Science Grad Students An Edge, Carol Hopper Brill
Out Of The Tower And Into The Classroom Or How Classroom Partnerships Give Marine Science Grad Students An Edge, Carol Hopper Brill
VIMS Articles
Ocean science graduate students face a challenge. They must prepare for two careers: research scientist and communication specialist. Successful researchers have to be creative, innovative, and competitive within their disciplines in order to promote their work and build collaborations among their peers. But, the higher stakes surrounding current environmental concerns, shifting public perceptions of science, and growing emphasis on broader impacts mean that scientists also have to be effective communicators, able to explain the value of their research to a wide audience. How do we effectively give graduate students an edge in preparing for this dual role?
Prediction Of The Export And Fate Of Global Ocean Net Primary Production: The Exports Science Plan, Da Siegel, Ko Buesseler, Et Al, Deborah K. Steinberg
Prediction Of The Export And Fate Of Global Ocean Net Primary Production: The Exports Science Plan, Da Siegel, Ko Buesseler, Et Al, Deborah K. Steinberg
VIMS Articles
Ocean ecosystems play a critical role in the Earth's carbon cycle and the quantification of their impacts for both present conditions and for predictions into the future remains one of the greatest challenges in oceanography. The goal of the EXport Processes in the Ocean from Remote Sensing (EXPORTS) Science Plan is to develop a predictive understanding of the export and fate of global ocean net primary production (NPP) and its implications for present and future climates. The achievement of this goal requires a quantification of the mechanisms that control the export of carbon from the euphotic zone as well as …
Faunal Communities Are Invariant To Fragmentation In Experimental Seagrass Landscapes, Jonathan S. Lefcheck, Scott R. Marion, Alfonso V. Lombana, R J. Orth
Faunal Communities Are Invariant To Fragmentation In Experimental Seagrass Landscapes, Jonathan S. Lefcheck, Scott R. Marion, Alfonso V. Lombana, R J. Orth
VIMS Articles
Human-driven habitat fragmentation is cited as one of the most pressing threats facing many coastal ecosystems today. Many experiments have explored the consequences of fragmentation on fauna in one foundational habitat, seagrass beds, but have either surveyed along a gradient of existing patchiness, used artificial materials to mimic a natural bed, or sampled over short timescales. Here, we describe faunal responses to constructed fragmented landscapes varying from 4-400 m(2) in two transplant garden experiments incorporating live eelgrass (Zostera marina L.). In experiments replicated within two subestuaries of the Chesapeake Bay, USA across multiple seasons and non-consecutive years, we comprehensively censused …
Contribution And Pathways Of Diazotroph-Derived Nitrogen To Zooplankton During The Vahine Mesocosm Experiment In The Oligotrophic New Caledonia Lagoon, Brian P. V. Hunt, Sophie Bonnet, Hugo Berthelot, Brandon J. Conroy, Rachel A. Foster, Marc Pagano
Contribution And Pathways Of Diazotroph-Derived Nitrogen To Zooplankton During The Vahine Mesocosm Experiment In The Oligotrophic New Caledonia Lagoon, Brian P. V. Hunt, Sophie Bonnet, Hugo Berthelot, Brandon J. Conroy, Rachel A. Foster, Marc Pagano
VIMS Articles
In oligotrophic tropical and subtropical oceans, where strong stratification can limit the replenishment of surface nitrate, dinitrogen (N-2) fixation by diazotrophs can represent a significant source of nitrogen (N) for primary production. The VAHINE (VAriability of vertical and tropHIc transfer of fixed N-2 in the south-wEst Pacific) experiment was designed to examine the fate of diazotroph-derived nitrogen (DDN) in such ecosystems. In austral summer 2013, three large ( similar to aEuro parts per thousand aEuro-50aEuro-m(3)) in situ mesocosms were deployed for 23 days in the New Caledonia lagoon, an ecosystem that typifies the low-nutrient, low-chlorophyll environment, to stimulate diazotroph production. …
Brief Communication: Breeding Vectors In The Phase Space Reconstructed From Time Series Data, Erin Lynch, Daniel Kaufman, A. Surjalal Sharma, Eugenia Kalnay, Kayo Ide
Brief Communication: Breeding Vectors In The Phase Space Reconstructed From Time Series Data, Erin Lynch, Daniel Kaufman, A. Surjalal Sharma, Eugenia Kalnay, Kayo Ide
VIMS Articles
Bred vectors characterize the nonlinear instability of dynamical systems and so far have been computed only for systems with known evolution equations. In this article, bred vectors are computed from a single time series data using time-delay embedding, with a new technique, nearest-neighbor breeding. Since the dynamical properties of the standard and nearest-neighbor breeding are shown to be similar, this provides a new and novel way to model and predict sudden transitions in systems represented by time series data alone.
Interannual And Seasonal Variabilities In Air-Sea Co2 Fluxes Along The Us Eastern Continental Shelf And Their Sensitivity To Increasing Air Temperatures And Variable Winds, Bronwyn Cahill, John Wilkin, Katja Fennel, Doug Vandemark, Marjorie A.M. Friedrichs
Interannual And Seasonal Variabilities In Air-Sea Co2 Fluxes Along The Us Eastern Continental Shelf And Their Sensitivity To Increasing Air Temperatures And Variable Winds, Bronwyn Cahill, John Wilkin, Katja Fennel, Doug Vandemark, Marjorie A.M. Friedrichs
VIMS Articles
Uncertainty in continental shelf air-sea CO2 fluxes motivated us to investigate the impact of interannual and seasonal variabilities in atmospheric forcing on the capacity of three shelf regions along the U.S. eastern continental shelf to act as a sink or source of atmospheric CO2. Our study uses a coupled biogeochemical-circulation model to simulate scenarios of present-day and future-perturbed mesoscale forcing variability. Overall, the U.S. eastern continental shelf acts as a sink for atmospheric CO2. There is a clear gradient in air-sea CO2 flux along the shelf region, with estimates ranging from -0.6MtCyr(-1) in the South Atlantic Bight (SAB) to -1.0MtCyr(-1) …
Effects Of Clam Aquaculture On Nektonic And Benthic Assemblages In Two Shallow-Water Estuaries, Mark Luckenbach, Jn Kraeuter, D Bushek
Effects Of Clam Aquaculture On Nektonic And Benthic Assemblages In Two Shallow-Water Estuaries, Mark Luckenbach, Jn Kraeuter, D Bushek
VIMS Articles
Aquaculture of the northern quahog (=hard clam) Mercenaria mercenaria (Linnaeus, 1758) is widespread in shallow waters of the United States from Cape Cod to the eastern Gulf of Mexico. Grow-out practices generally involve bottom planting and the use of predator exclusion mesh. Both the extent and scale of clam farms have increased in recent decades resulting in concerns regarding the impacts of these practices on estuarine fauna. Seasonal distribution, abundance, biomass, species richness, and community composition of nektonic, demersal, epibenthic, and infaunal organisms were examined in cultivated and uncultivated shallow-water habitats in Virginia and New Jersey. The results reveal that …
Effects Of Predator Richness And Habitat Heterogeneity On Prey Suppression In An Estuarine Food Chain, Leonardo K. Miyashita, J. Paul Richardson, J. Emmett Duffy
Effects Of Predator Richness And Habitat Heterogeneity On Prey Suppression In An Estuarine Food Chain, Leonardo K. Miyashita, J. Paul Richardson, J. Emmett Duffy
VIMS Articles
Predator influence on the structure of prey communities can be mediated by habitat heterogeneity, the effects of which may cascade to the base of the food webs, altering producer biomass and species composition. We carried out a mesocosm experiment manipulating the identity and richness of predators and habitat heterogeneity to test their influence on resource use effectiveness, competition among predators, and trophic cascades in a model estuarine system with 3 trophic levels (microalgae, mysids, and the predators blue crab Callinectes sapidus, sand shrimp Crangon septemspinosa, and grass shrimp Palaemonetes pugio). We hypothesized that increasing predator species richness would increase mysid …
Moving Forward 21st Century Pathways To Strengthen The Ocean Science Workforce Through Graduate Education And Professional Development, Linda C. Schaffner, T. W. Hartley, J. G. Saunders
Moving Forward 21st Century Pathways To Strengthen The Ocean Science Workforce Through Graduate Education And Professional Development, Linda C. Schaffner, T. W. Hartley, J. G. Saunders
VIMS Articles
The scope of emerging national and international ocean-related issues facing society demands that we develop broad perspectives on graduate education and training in the ocean sciences. A multifaceted ocean workforce and new kinds of intellectual partnerships are needed to address ocean science research priorities, strengthen our understanding of coupled human-natural ocean systems, engage and inform public policy and management decision making, and increase ocean literacy. Alumni from graduate programs in ocean sciences are following diverse career paths in academia, government, nongovernmental organizations, and industry, and thus can inform us about the diverse skills needed to succeed. The ocean science academic …
Chemical Formation Of Hybrid Di-Nitrogen Calls Fungal Codenitrification Into Question, Rebecca L. Phillips, Bk Song, Andrew M. S. Mcmillan, Gwen Grelet, Bevan S. Weir, Thilak Palmada, Craig Tobias
Chemical Formation Of Hybrid Di-Nitrogen Calls Fungal Codenitrification Into Question, Rebecca L. Phillips, Bk Song, Andrew M. S. Mcmillan, Gwen Grelet, Bevan S. Weir, Thilak Palmada, Craig Tobias
VIMS Articles
Removal of excess nitrogen (N) can best be achieved through denitrification processes that transform N in water and terrestrial ecosystems to di-nitrogen (N-2) gas. The greenhouse gas nitrous oxide (N2O) is considered an intermediate or end-product in denitrification pathways. Both abiotic and biotic denitrification processes use a single N source to form N2O. However, N-2 can be formed from two distinct N sources (known as hybrid N-2) through biologically mediated processes of anammox and codenitrification. We questioned if hybrid N-2 produced during fungal incubation at neutral pH could be attributed to abiotic nitrosation and if N2O was consumed during N-2 …
Responses Of Antarctic Marine And Freshwater Ecosystems To Changing Ice Conditions, Mk Obryk, Pt Doran, Et Al, Deborah K. Steinberg, Hw Ducklow
Responses Of Antarctic Marine And Freshwater Ecosystems To Changing Ice Conditions, Mk Obryk, Pt Doran, Et Al, Deborah K. Steinberg, Hw Ducklow
VIMS Articles
Polar regions are warming more rapidly than lower latitudes, and climate models predict that this trend will continue into the coming decades. Despite these observations and predictions, relatively little is known about how polar ecosystems have responded and will continue to respond to this change. Two Long-Term Ecological Research (LTER) sites, located in contrasting environments in Antarctica, have been studying marine and aquatic terrestrial ecosystems for more than two decades. We use data from these research areas to show that the extent and thickness of ice covers are highly sensitive to short- and long-term climate variation and that this variation …
Why Biodiversity Is Important To The Functioning Of Real-World Ecosystems, Da Siegel, Ko Buessler, Et Al, Deborah K. Steinberg
Why Biodiversity Is Important To The Functioning Of Real-World Ecosystems, Da Siegel, Ko Buessler, Et Al, Deborah K. Steinberg
VIMS Articles
Ocean ecosystems play a critical role in the Earth's carbon cycle and the quantification of their impacts for both present conditions and for predictions into the future remains one of the greatest challenges in oceanography. The goal of the EXport Processes in the Ocean from Remote Sensing (EXPORTS) Science Plan is to develop a predictive understanding of the export and fate of global ocean net primary production (NPP) and its implications for present and future climates. The achievement of this goal requires a quantification of the mechanisms that control the export of carbon from the euphotic zone as well as …