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Full-Text Articles in Aquaculture and Fisheries
Temperature Effects On Growth, Colony Development And Carbon Partitioning In Three Phaeocystis Species, Xd Wang, Kw Tang, Y Wang, Walker O. Smith Jr.
Temperature Effects On Growth, Colony Development And Carbon Partitioning In Three Phaeocystis Species, Xd Wang, Kw Tang, Y Wang, Walker O. Smith Jr.
VIMS Articles
Phaeocystis is an ecologically important marine phytoplankton genus that is globally distributed. We examined the effects of temperature on the 3 most common species: P. globosa, P. antarctica, and P. pouchetii, which grew at 16-32, 0-6, and 4-8 degrees C, respectively. P. pouchetii did not form colonies; P. globosa formed colonies at 16, 20, and 24 degrees C, and P. antarctica colonies were observed at all temperatures. More cells were partitioned into the colonial form at lower temperatures than at higher temperatures for P. globosa and P. antarctica. P. globosa colony size decreased with temperature, whereas P. antarctica colony size …
Challenges Of Modeling Depth-Integrated Marine Primary Productivity Over Multiple Decades: A Case Study At Bats And Hot, Vs Saba, Mam Friedrichs, Me Carr, D Antoine, Ra Armstrong, Et Al.
Challenges Of Modeling Depth-Integrated Marine Primary Productivity Over Multiple Decades: A Case Study At Bats And Hot, Vs Saba, Mam Friedrichs, Me Carr, D Antoine, Ra Armstrong, Et Al.
VIMS Articles
The performance of 36 models (22 ocean color models and 14 biogeochemical ocean circulation models (BOGCMs)) that estimate depth-integrated marine net primary productivity (NPP) was assessed by comparing their output to in situ C-14 data at the Bermuda Atlantic Time series Study (BATS) and the Hawaii Ocean Time series (HOT) over nearly two decades. Specifically, skill was assessed based on the models' ability to estimate the observed mean, variability, and trends of NPP. At both sites, more than 90% of the models underestimated mean NPP, with the average bias of the BOGCMs being nearly twice that of the ocean color …
Dead In The Water: The Fate Of Copepod Carcasses In The York River Estuary, Virginia, Dt Elliott, Courtney K. Harris, Kw Tang
Dead In The Water: The Fate Of Copepod Carcasses In The York River Estuary, Virginia, Dt Elliott, Courtney K. Harris, Kw Tang
VIMS Articles
Using laboratory and field experiments we investigated three fates of copepod carcass organic matter in the York River estuary, Virginia: ingestion by planktivores (necrophagy), microbial decomposition, and removal by gravitational settling in the presence of turbulence (sinking). The ctenophore Mnemiopsis leidyi ingested live copepods and carcasses indiscriminately in feeding experiments. Microbial decomposition led to ca. 50% of carcass dry weight loss within 8 h after death. Carcass settling velocities in still water were ca. 0.1 cm s(-1), implying short residence time (hours) in the shallow estuary. However, turbulent mixing kept carcasses in suspension much of the time, reducing sinking losses. …
Bacteria Dispersal By Hitchhiking On Zooplankton, Hp Grossart, C Dziallas, F Leunert, Kw Tang
Bacteria Dispersal By Hitchhiking On Zooplankton, Hp Grossart, C Dziallas, F Leunert, Kw Tang
VIMS Articles
Microorganisms and zooplankton are both important components of aquatic food webs. Although both inhabit the same environment, they are often regarded as separate functional units that are indirectly connected through nutrient cycling and trophic cascade. However, research on pathogenic and nonpathogenic bacteria has shown that direct association with zooplankton has significant influences on the bacteria's physiology and ecology. We used stratified migration columns to study vertical dispersal of hitchhiking bacteria through migrating zooplankton across a density gradient that was otherwise impenetrable for bacteria in both upward and downward directions (conveyor-belt hypothesis). The strength of our experiments is to permit quantitative …
Subtle Biological Responses To Increased Co2 Concentrations By Phaeocystis Globosa Scherffel, A Harmful Algal Bloom Species, Y Wang, Wo Smith, Xd Wang, Ss Li
Subtle Biological Responses To Increased Co2 Concentrations By Phaeocystis Globosa Scherffel, A Harmful Algal Bloom Species, Y Wang, Wo Smith, Xd Wang, Ss Li
VIMS Articles
Recent investigations into the role of carbon dioxide on phytoplankton growth and composition have clearly shown differential effects among species and assemblages, suggesting that increases in oceanic CO2 may play a critical role in structuring lower trophic levels of marine systems in the future. Furthermore, alarming increases in the occurrence of harmful algal blooms (HABs) in coastal waters have been observed, and while not uniform among systems, appear in some manner to be linked to human impacts (eutrophication) on coastal systems. Models of HABs are in their infancy and do not at present include sophisticated biological effects or their environmental …
Kin Structure, Ecology And The Evolution Of Social Organization In Shrimp: A Comparative Analysis, Je Duffy, Ks Macdonald
Kin Structure, Ecology And The Evolution Of Social Organization In Shrimp: A Comparative Analysis, Je Duffy, Ks Macdonald
VIMS Articles
Eusocial societies present a Darwinian paradox, yet they have evolved independently in insects, mole-rats and symbiotic shrimp. Historically, eusociality has been thought to arise as a response to ecological challenges, mediated by kin selection, but the role of kin selection has recently been questioned. Here we use phylogenetically independent contrasts to test the association of eusociality with ecological performance and genetic structure (via life history) among 20 species of sponge-dwelling shrimp (Synalpheus) in Belize. Consistent with hypotheses that cooperative groups enjoy an advantage in challenging habitats, we show that eusocial species are more abundant, occupy more sponges and have broader …
Production Of Dissolved Organic Matter And Inorganic Nutrients By Gelatinous Zooplankton In The York River Estuary, Chesapeake Bay, Rh Condon, Dk Steinberg, Da Bronk
Production Of Dissolved Organic Matter And Inorganic Nutrients By Gelatinous Zooplankton In The York River Estuary, Chesapeake Bay, Rh Condon, Dk Steinberg, Da Bronk
VIMS Articles
Large "blooms" of ctenophores (Mnemiopsis leidyi) and scyphomedusae (Chrysaora quinquecirrha) occur throughout the York River, a sub-estuary of Chesapeake Bay. These gelatinous zooplankton blooms can influence carbon (C) and nutrient cycling through excretion of dissolved organic matter (DOM), and inorganic nitrogen (N) and phosphorus (P). We measured dissolved organic carbon, nitrogen and phosphorus (DOC, DON and DOP), ammonium (NH(4)(+)) and phosphate (PO(4)(3-)) released by M. leidyi and C. quinquecirrha in the laboratory, and estimated their contribution to in situ DOC and inorganic pools. Both species released high amounts of DOC compared with DON and DOP. DOM released by Mnemiopsis was …
Nitrogen Uptake By Phytoplankton And Bacteria During An Induced Phaeocystis Pouchetii Bloom, Measured Using Size Fractionation And Flow Cytometric Sorting, Pb Bradley, Mp Sanderson, Jc Nejstgaard, Af Sazhin, Me Frischer, Lm Killberg-Thoreson, Pg Verity, L Campbell, Da Bronk
Nitrogen Uptake By Phytoplankton And Bacteria During An Induced Phaeocystis Pouchetii Bloom, Measured Using Size Fractionation And Flow Cytometric Sorting, Pb Bradley, Mp Sanderson, Jc Nejstgaard, Af Sazhin, Me Frischer, Lm Killberg-Thoreson, Pg Verity, L Campbell, Da Bronk
VIMS Articles
Uptake of inorganic and organic nitrogen (N) by phytoplankton and bacteria was investigated during a mesocosm study conducted in Raunefjord, Norway in April 2005. One mesocosm was fertilized with nitrate and phosphate at a ratio of 16:1 and maintained in the light, while one unamended light mesocosm served as a control. Dissolved nutrients, phytoplankton and bacterial biomass, and phytoplankton community composition were monitored throughout the 26 d experiment. Uptake of (15)N-labeled ammonium and nitrate, and dual-labeled ((15)N and (13)C) urea and dissolved free amino acids (DFAA) was measured for phytoplankton and bacteria using 2 methods: size fractionation into 0.2-0.8 and …
Linkage Between Crustacean Zooplankton And Aquatic Bacteria, Kw Tang, V Turk, Hp Grossart
Linkage Between Crustacean Zooplankton And Aquatic Bacteria, Kw Tang, V Turk, Hp Grossart
VIMS Articles
Bacteria and metazoan zooplankton (mainly crustaceans) are often viewed as 2 separate functional groups in the pelagic food webs indirectly linked via nutrient cycling and trophic cascades. Yet a zooplankter's body carries a high abundance of diverse bacteria, often at an equivalent concentration orders of magnitude higher than the ambient bacterial concentration. Zooplankton bodies are organic-rich micro-environments that support fast bacterial growth. Their physical-chemical conditions differ from those in the surrounding water and therefore select for different bacterial communities, including anaerobic bacteria that otherwise may not thrive in a well-oxygenated water column. The zooplankton body provides protection to the associated …
High Particle Export Over The Continental Shelf Of The West Antarctic Peninsula, Ko Buesseler, Amp Mcdonnell, Ome Schofield, Dk Steinberg, Hw Ducklow
High Particle Export Over The Continental Shelf Of The West Antarctic Peninsula, Ko Buesseler, Amp Mcdonnell, Ome Schofield, Dk Steinberg, Hw Ducklow
VIMS Articles
Drifting cylindrical traps and the flux proxy Th-234 indicate more than an order of magnitude higher sinking fluxes of particulate carbon and Th-234 in January 2009 than measured by a time-series conical trap used regularly on the shelf of the west Antarctic Peninsula (WAP). The higher fluxes measured in this study have several implications for our understanding of the WAP ecosystem. Larger sinking fluxes result in a revised export efficiency of at least 10% (C flux/net primary production) and a requisite lower regeneration efficiency in surface waters. High fluxes also result in a large supply of sinking organic matter to …