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- Biological Sciences Peer-Reviewed Articles (4)
- Physical Sciences Peer-Reviewed Articles (2)
- Bacterioplankton; microbial foodweb; carbon cycle; Antarctica; Phaeocystis (1)
- DOC remineralization; bacterial respiration; TCO2; growth efficiency; carbon conversion factor (1)
- Ice-Edge Zone; Weddell Sea; Primary Productivity; Organic-Carbon; Bloom Dynamics (1)
Articles 1 - 6 of 6
Full-Text Articles in Physical Sciences and Mathematics
Seawifs Satellite Ocean Color Data From The Southern Ocean, Jk Moore, Mr Abbott, Rg Richman, Walker O. Smith Jr., Et Al
Seawifs Satellite Ocean Color Data From The Southern Ocean, Jk Moore, Mr Abbott, Rg Richman, Walker O. Smith Jr., Et Al
VIMS Articles
SeaWiFS estimates of surface chlorophyll concentrations are reported for the region of the U.S. JGOFS study in the Southern Ocean (similar to 170 degrees W, 60 degrees S). Elevated chlorophyll was observed at the Southern Ocean fronts, near the edge of the seasonal ice sheet, and above the Pacific-Antarctic Ridge. The elevated chlorophyll levels associated with the Pacific-Antarctic Ridge are surprising since even the crest of the ridge is at depths > 2000 m. This elevated phytoplankton biomass is likely the result of mesoscale physical-biological interactions where the Antarctic Circumpolar Current (ACC) encounters the ridge. Four cruises surveyed this region between …
Radiocarbon In Marine Bacteria: Evidence For The Ages Of Assimilated Carbon, J Cherrier, Je Bauer, Et Al
Radiocarbon In Marine Bacteria: Evidence For The Ages Of Assimilated Carbon, J Cherrier, Je Bauer, Et Al
VIMS Articles
It is generally accepted that marine bacteria utilize labile, recently produced components of bulk dissolved organic matter. This interpretation is based largely on indirect measurements using model compounds and plankton-derived organic matter. Here, we present an assessment of the relative proportions of modem and older dissolved organic carbon (DOC) utilized by marine bacteria. Bacterial nucleic acids were collected from both estuarine (Santa Rosa Sound, FL) and open-ocean (eastern North Pacific) sites, and the natural radiocarbon signatures of the nucleic acid carbon in both systems were determined. Bacterial nucleic acids from Santa Rosa Sound were significantly enriched in radiocarbon with respect …
Measurements Of The Shape Of Sand Ripples, Jerome P-Y Maa, S-H Ou, C-J Huang
Measurements Of The Shape Of Sand Ripples, Jerome P-Y Maa, S-H Ou, C-J Huang
VIMS Articles
Laboratory experiments have been conductef. for determining what would be the correct selection of acoustic devices for measuring the shape of sand ripples. The results reveal that a toneburst type signal generator with I or 2 watts will be sufficient to drive the transducer. A transducer with focus and reasonable size would be the best choice. While measuring, the ratio of measuring distance (between the transducer and sea floor) and the transducer's focus length should be maintained at a ratio between 90% and II 0% for best results.
Estimation Of Bacterial Respiration And Growth Efficiency In The Ross Sea, Antarctica, C. A. Carlson, N. R. Bates, H. W. Ducklow, D. A. Hansell
Estimation Of Bacterial Respiration And Growth Efficiency In The Ross Sea, Antarctica, C. A. Carlson, N. R. Bates, H. W. Ducklow, D. A. Hansell
VIMS Articles
Seawater cultures were conducted in large volume (36 l) gas impermeable tri-laminate bags for the purpose of empirically deriving bacterial growth efficiency (BGE) and carbon conversion factors (CCF) in the south central Ross Sea. This experimental design allowed for concomitant measurements of metabolic reactants (loss of total and dissolved organic carbon [TOC and DOG]) and products (gain of total carbon dioxide [TCO2] and bacterial biomass) to be made from a single incubation vessel. Some previous studies have relied on proxy measurements (e.g. O-2, H-3-thymidine incorporation and cell abundance) to determine BGE and CCF rather than direct carbon measurements. Our experimental …
Bacterial Growth In Experimental Plankton Assemblages And Seawater Cultures From The Phaeocystis Antarctica Bloom In The Ross Sea, Antarctica, H. W. Ducklow, C. Carlson, Walker O. Smith Jr.
Bacterial Growth In Experimental Plankton Assemblages And Seawater Cultures From The Phaeocystis Antarctica Bloom In The Ross Sea, Antarctica, H. W. Ducklow, C. Carlson, Walker O. Smith Jr.
VIMS Articles
A series of seawater culture experiments was carried out during the Phaeocystis antarctica bloom in the Ross Sea polynya (76.5 degrees S, 180 degrees W; November to December 1994 and December 1995 to January 1996) to examine bacterioplankton growth and derive empirical factors for estimating bacterial production rates. Bacterial growth was exponential over 3 to 10 d in all experiments, at rates of ca 0.1 to 0.7 d(-1), even in persistently cold waters (-2 to + 1 degrees C). Growth rates were lower in the early part of the bloom (early to mid-November) and highest during the period of peak …
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 …