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Full-Text Articles in Life Sciences
An Operational Overview Of The Export Processes In The Ocean From Remote Sensing (Exports) Northeast Pacific Field Deployment, David A. Siegel, Ivona Cetinic, (...), Deborah K. Steinberg, Et Al
An Operational Overview Of The Export Processes In The Ocean From Remote Sensing (Exports) Northeast Pacific Field Deployment, David A. Siegel, Ivona Cetinic, (...), Deborah K. Steinberg, Et Al
VIMS Articles
The goal of the EXport Processes in the Ocean from RemoTe Sensing (EXPORTS) field campaign is to develop a predictive understanding of the export, fate, and carbon cycle impacts of global ocean net primary production. To accomplish this goal, observations of export flux pathways, plankton community composition, food web processes, and optical, physical, and biogeochemical (BGC) properties are needed over a range of ecosystem states. Here we introduce the first EXPORTS field deployment to Ocean Station Papa in the Northeast Pacific Ocean during summer of 2018, providing context for other papers in this special collection. The experiment was conducted with …
Relative Impacts Of Global Changes And Regional Watershed Changes On The Inorganic Carbon Balance Of The Chesapeake Bay, Pierre St-Laurent, Marjorie A.M. Friedrichs, Raymond G. Najjar, Elizabeth Shadwick, Hanquin Tian, Yuanzhi Yao
Relative Impacts Of Global Changes And Regional Watershed Changes On The Inorganic Carbon Balance Of The Chesapeake Bay, Pierre St-Laurent, Marjorie A.M. Friedrichs, Raymond G. Najjar, Elizabeth Shadwick, Hanquin Tian, Yuanzhi Yao
VIMS Articles
The Chesapeake Bay is a large coastal-plain estuary that has experienced considerable anthropogenic changeover the past century. At the regional scale, land-use change has doubled the nutrient input from rivers and led to an increase in riverine carbon and alkalinity. The bay has also experienced global changes, including the rise of atmospheric temperature and CO2. Here we seek to understand the relative impact of these changes on the inorganic carbon balance of the bay between the early 1900s and the early 2000s. We use a linked land–estuarine–ocean modeling system that includes both inorganic and organic carbon and nitrogen cycling. Sensitivity …
Zooplankton Diel Vertical Migration During Antarctic Summer, John A. Conroy, Deborah K. Steinberg, Patrica S. Thibodeau, Oscar Schofield
Zooplankton Diel Vertical Migration During Antarctic Summer, John A. Conroy, Deborah K. Steinberg, Patrica S. Thibodeau, Oscar Schofield
VIMS Articles
Zooplankton diel vertical migration (DVM) during summer in the polar oceans is presumed to be dampened due to near continuous daylight. We analyzed zooplankton diel vertical distribution patterns in a wide range of taxa along the Western Antarctic Peninsula (WAP) to assess if DVM occurs, and if so, what environmental controls modulate DVM in the austral summer. Zooplankton were collected during January and February in paired day-night, depth-stratified tows through the mesopelagic zone along the WAP from 2009-2017, as well as in day and night epipelagic net tows from 1993-2017. The copepod Metridia gerlachei, salp Salpa thompsoni, pteropod …
The Importance Of Antarctic Krill In Biogeochemical Cycles, El Cavan, A Belcher, Sl Hill, S Kawaguchi, S Mccormack, B Meyer, S Nicol, K Schmidt, Deborah K. Steinberg, Ga Tarling, Pw Boyd
The Importance Of Antarctic Krill In Biogeochemical Cycles, El Cavan, A Belcher, Sl Hill, S Kawaguchi, S Mccormack, B Meyer, S Nicol, K Schmidt, Deborah K. Steinberg, Ga Tarling, Pw Boyd
VIMS Articles
Antarctic krill (Euphausia superba) are swarming, oceanic crustaceans, up to two inches long, and best known as prey for whales and penguins – but they have another important role. With their large size, high biomass and daily vertical migrations they transport and transform essential nutrients, stimulate primary productivity and influence the carbon sink. Antarctic krill are also fished by the Southern Ocean’s largest fishery. Yet how krill fishing impacts nutrient fertilisation and the carbon sink in the Southern Ocean is poorly understood. Our synthesis shows fishery management should consider the influential biogeochemical role of both adult and larval …
It’S About Time: A Synthesis Of Changing Phenology In The Gulf Of Maine Ecosystem, Md Staudinger, Ke Mills, Et Al, David S. Johnson, Et Al
It’S About Time: A Synthesis Of Changing Phenology In The Gulf Of Maine Ecosystem, Md Staudinger, Ke Mills, Et Al, David S. Johnson, Et Al
VIMS Articles
The timing of recurring biological and seasonal environmental events is changing on a global scale relative to temperature and other climate drivers. This study considers the Gulf of Maine ecosystem, a region of high social and ecological importance in the Northwest Atlantic Ocean and synthesizes current knowledge of (a) key seasonal processes, patterns, and events; (b) direct evidence for shifts in timing; (c) implications of phenological responses for linked ecological-human systems; and (d) potential phenology-focused adaptation strategies and actions. Twenty studies demonstrated shifts in timing of regional marine organisms and seasonal environmental events. The most common response was earlier timing, …
Alkalinity In Tidal Tributaries Of The Chesapeake Bay, R. G. Najjar, M. Herrmann, S. M. Cintrón Del Valle, Jaclyn R. Friedman, Marjorie A.M. Friedrichs, Et Al
Alkalinity In Tidal Tributaries Of The Chesapeake Bay, R. G. Najjar, M. Herrmann, S. M. Cintrón Del Valle, Jaclyn R. Friedman, Marjorie A.M. Friedrichs, Et Al
VIMS Articles
Despite the important role of alkalinity in estuarine carbon cycling, the seasonal and decadal variability of alkalinity, particularly within multiple tidal tributaries of the same estuary, is poorly understood. Here we analyze more than 25,000 alkalinity measurements, mostly from the 1980s and 1990s,in the major tidal tributaries of the Chesapeake Bay, a large, coastal‐plain estuary of eastern North America.The long‐term means of alkalinity in tidal‐fresh waters vary by a factor of 6 among seven tidal tributaries,reflecting the alkalinity of nontidal rivers draining to these estuaries. At 25 stations, mostly in the Potomac River Estuary, wefind significant long‐term increasing trends that …
Ocean Change Within Shoreline Communities: From Biomechanics To Behaviour And Beyond, Brian Gaylord, Kristina M. Barclay, Brittany M. Jellison, Laura L. Jurgens, Aaron T. Ninokawa, Emily B. Rivest, Lindsey R. Leighton
Ocean Change Within Shoreline Communities: From Biomechanics To Behaviour And Beyond, Brian Gaylord, Kristina M. Barclay, Brittany M. Jellison, Laura L. Jurgens, Aaron T. Ninokawa, Emily B. Rivest, Lindsey R. Leighton
VIMS Articles
Humans are changing the physical properties of Earth. In marine systems, elevated carbon dioxide concentrations are driving notable shifts in temperature and seawater chemistry. Here, we consider consequences of such perturbations for organism biomechanics and linkages amongst species within communities.In particular,we examine case examples of altered morphologies and material properties, disrupted consumer–prey behaviours, and the potential for modulated positive (i.e. facilitative) interactions amongst taxa, as incurred through increasing ocean acidity and rising temperatures. We focus on intertidal rocky shores of temperate seas as model systems, acknowledging the longstanding role of these communities in deciphering ecological principles. Our survey illustrates the …
Preliminary Estimate Of Contribution Of Arctic Nitrogen Fixation To The Global Nitrogen Budget, Rachel E. Sipler, Donglai Gong, Se Baer, Mp Sanderson, Qn Roberts, M Mulholland, Da Bronk
Preliminary Estimate Of Contribution Of Arctic Nitrogen Fixation To The Global Nitrogen Budget, Rachel E. Sipler, Donglai Gong, Se Baer, Mp Sanderson, Qn Roberts, M Mulholland, Da Bronk
VIMS Articles
Dinitrogen (N-2) fixation is the source of all biologically available nitrogen on earth, and its presence or absence impacts net primary production and global biogeochemical cycles. Here, we report rates of 3.5-17.2 nmol N L-1 d(-1) in the ice-free coastal Alaskan Arctic to show that N-2 fixation in the Arctic Ocean may be an important source of nitrogen to a seasonally nitrogen-limited system. If widespread in surface waters over ice-free shelves throughout the Arctic, N-2 fixation could contribute up to 3.5 Tg N yr(-1) to the Arctic nitrogen budget. At these rates, N-2 fixation occurring in ice-free summer waters would …
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 …
Regional Differences In Quality Of Krill And Fish As Prey Along The Western Antarctic Peninsula, Kate E. Ruck, Deborah K. Steinberg, Elizabeth A. Canuel
Regional Differences In Quality Of Krill And Fish As Prey Along The Western Antarctic Peninsula, Kate E. Ruck, Deborah K. Steinberg, Elizabeth A. Canuel
VIMS Articles
The warming trend in the northern part of the Western Antarctic Peninsula (WAP) has led to a decrease in perennial and summer sea ice, an increase in heat content over the shelf, and lower phytoplankton biomass, which could affect the prey quality of krill and fish that are utilized by apex predators. We compared prey quality metrics, including elemental (C, N) content; total, neutral, and polar lipid content; and energy densities of known penguin prey items including krill (Euphausia superba, Thysanoessa macrura, and E. crystallorophias) and fish (silverfish Pleuragramma antarcticum and the myctophid Electrona antarctica) …
Long-Term Time-Series Study Of Salp Population Dynamics In The Sargasso Sea, Joshua P. Stone, Deborah K. Steinberg
Long-Term Time-Series Study Of Salp Population Dynamics In The Sargasso Sea, Joshua P. Stone, Deborah K. Steinberg
VIMS Articles
Salps are bloom-forming, pelagic tunicates with high grazing rates on phytoplankton, with the potential to greatly increase vertical particle flux through rapidly sinking fecal pellets. However, the frequency and causes of salp blooms are not well known. We quantified salps from day and night zooplankton net tows in the epipelagic zone of the North Atlantic subtropical gyre as part of the Bermuda Atlantic Time-series Study (BATS). Salp species and size were quantified in biweekly to monthly tows from April 1994 to November 2011. Twenty-one species of salps occurred at the BATS site over this time period, and the most common …
Two Decades Of Pelagic Ecology Of The Western Antarctic Peninsula, Deborah K. Steinberg, D G. Martinson, D P. Costa
Two Decades Of Pelagic Ecology Of The Western Antarctic Peninsula, Deborah K. Steinberg, D G. Martinson, D P. Costa
VIMS Articles
Significant strides in our understanding of the marine pelagic ecosystem of the Western Antarctic Peninsula (WAP) region have been made over the past two decades, resulting from research conducted aboard ARSV Laurence M. Gould and RVIB Nathaniel B. Palmer. These advances range from an understanding of the physical forcing on biology, to food web ecology (from microbes to top predators), to biogeochemical cycling, often in the larger context of rapid climate warming in the region. The proximity of the WAP to the Antarctic Circumpolar Current and WAP continental shelf bathymetry affects the hydrography and helps structure the biological community. Seasonal, …
Synergistic Effects Of Iron And Temperature On Antarctic Phytoplankton And Microzooplankton Assemblages, J. M. Rose, Y. Feng, Et Al, Walker O. Smith Jr., B. Sigist, S. Tozzi, Et Al
Synergistic Effects Of Iron And Temperature On Antarctic Phytoplankton And Microzooplankton Assemblages, J. M. Rose, Y. Feng, Et Al, Walker O. Smith Jr., B. Sigist, S. Tozzi, Et Al
VIMS Articles
Iron availability and temperature are important limiting factors for the biota in many areas of the world ocean, and both have been predicted to change in future climate scenarios. However, the impacts of combined changes in these two key factors on microbial trophic dynamics and nutrient cycling are unknown. We examined the relative effects of iron addition (+1 nM) and increased temperature (+4 degrees C) on plankton assemblages of the Ross Sea, Antarctica, a region characterized by annual algal blooms and an active microbial community. Increased iron and temperature individually had consistently significant but relatively minor positive effects on total …
The Microbial And Metazoan Community Associated With Colonies Of Trichodesmium Spp.: A Quantitative Survey, Cc Sheridan, Deborah K. Steinberg, Gw Kling
The Microbial And Metazoan Community Associated With Colonies Of Trichodesmium Spp.: A Quantitative Survey, Cc Sheridan, Deborah K. Steinberg, Gw Kling
VIMS Articles
Association with resource-rich particles may benefit a number of planktonic species in oligotriphic, open-ocean regimes. This study examined communities of microbes and Zooplankton associated with colonies of the cyanobacterium Trichodesmium spp. in the Sargasso Sea. Trichodesmium colonies and seawater controls were collected near Bermuda using SCUBA during September 1995, and June, July and August 1996. Organisms associated with the colonies and those in the surrounding seawater were enumerated using light and fluorescence microscopy. We found that 85% of the Trichodesmium puff and tuft colonies examined harbored associated organisms. Associated organisms included bacteria (rod and coccoid),fungi, pennate diatoms, centric diatoms, heterotrophic …
Phytoplankton Growth Rates In The Ross Sea, Antarctica, Determined By Independent Methods: Temporal Variations, Walker O. Smith Jr., D. M. Nelson, S. Mathot
Phytoplankton Growth Rates In The Ross Sea, Antarctica, Determined By Independent Methods: Temporal Variations, Walker O. Smith Jr., D. M. Nelson, S. Mathot
VIMS Articles
The development of the seasonal phytoplankton bloom in the Ross Sea was studied during two cruises. The first, conducted in November-December 1994, investigated the initiation and rapid growth of the bloom, whereas the second (December 1995-January 1996) concentrated on the bloom's maximum biomass period and the subsequent decline in biomass. Central to the understanding of the controls of growth and the summer decline of the bloom is a quantitative assessment of the growth rate of phytoplankton. Growth rates were estimated over two time scales with different methods. The first estimated daily growth rates from isotopic incorporation under simulated in situ …