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- Biological Sciences Peer-Reviewed Articles (3)
- Physical Sciences Peer-Reviewed Articles (3)
- Circumpolar Deep-Water; Crab-Eater Seals; Continental-Shelf; Spatiotemporal Variability (1)
- Denitrification; dissolved organic carbon; grass clippings; lipid biomarkers; nitrogen; organic carbon; stable isotopes; stream restoration (1)
- Western Weddell Sea; Algae; Evolution (1)
Articles 1 - 6 of 6
Full-Text Articles in Physical Sciences and Mathematics
Influence Of Natural And Novel Organic Carbon Sources On Denitrification In Forest, Degraded Urban, And Restored Streams, Ta Newcomer, Ss Kaushal, Pm Mayer, Ar Shields, Elizabeth A. Canuel, Et Al
Influence Of Natural And Novel Organic Carbon Sources On Denitrification In Forest, Degraded Urban, And Restored Streams, Ta Newcomer, Ss Kaushal, Pm Mayer, Ar Shields, Elizabeth A. Canuel, Et Al
VIMS Articles
Organic carbon is important in regulating ecosystem function, and its source and abundance may be altered by urbanization. We investigated shifts in organic carbon quantity and quality associated with urbanization and ecosystem restoration, and its potential effects on denitrification at the riparian-stream interface. Field measurements of streamwater chemistry, organic carbon characterization, and laboratory-based denitrification experiments were completed at two forested, two restored, and two unrestored urban streams at the Baltimore Long-Term Ecological Research site, Maryland, USA. Dissolved organic carbon (DOC) and nitrate loads increased with runoff according to a power-law function that varied across sites. Stable isotopes and molar C:N …
Impact Of Diatom-Diazotroph Associations On Carbon Export In The Amazon River Plume, Ly Yeung, Wm Berelsen, Et Al, Deborah K. Steinberg, Et Al
Impact Of Diatom-Diazotroph Associations On Carbon Export In The Amazon River Plume, Ly Yeung, Wm Berelsen, Et Al, Deborah K. Steinberg, Et Al
VIMS Articles
Offshore tropical river plumes are associated with areas of high N-2 fixation (diazotrophy) and biological carbon drawdown. Episodic blooms of the diatom Hemiaulus hauckii and its diazotrophic cyanobacterial symbiont Richelia intracellularis are believed to dominate that carbon drawdown, but the mechanism is not well understood. We report primary productivity associated with blooms of these diatom-diazotroph assemblages (DDAs) in the offshore plume of the Amazon River using simultaneous measurements of O-2/Ar ratios and the triple-isotope composition of dissolved O-2. In these blooms, we observe peaks in net community productivity, but relatively small changes in gross primary productivity, suggesting that DDA blooms …
Near-Synchronous And Delayed Initiation Of Long Run-Out Submarine Sediment Flows From A Record-Breaking River Flood, Offshore Taiwan, L. Carter, Jd Milliman, Pj Talling, R Gavey, Rb Wynn
Near-Synchronous And Delayed Initiation Of Long Run-Out Submarine Sediment Flows From A Record-Breaking River Flood, Offshore Taiwan, L. Carter, Jd Milliman, Pj Talling, R Gavey, Rb Wynn
VIMS Articles
Subsea fiber-optic telecommunication cables can break under fast sediment flows that travel 100s of kilometers through the deep ocean in response to earthquakes and submarine landslides. Similar flows are inferred to form from major river floods whose sediment-laden waters plunge and travel along the seabed. However, the complex initiation of flood-related flows and their hazard potential have not been observed until now. Here we use cable fault data from the Gaoping Canyon/Manila Trench off Taiwan to show that a major river flood, formed during Typhoon Morakot (2009), generated two, long run-out, destructive sediment flows; one during peak flood and the …
Chlorophyll A In Antarctic Sea Ice From Historical Ice Core Data, Km Meiners, M Vancoppenolle, S Thanassekos, Gs Dieckmann, Dn Thomas, .. .., Walker O. Smith Jr., Et Al
Chlorophyll A In Antarctic Sea Ice From Historical Ice Core Data, Km Meiners, M Vancoppenolle, S Thanassekos, Gs Dieckmann, Dn Thomas, .. .., Walker O. Smith Jr., Et Al
VIMS Articles
Sea ice core chlorophyll a data are used to describe the seasonal, regional and vertical distribution of algal biomass in Southern Ocean pack ice. The Antarctic Sea Ice Processes and Climate - Biology (ASPeCt - Bio) circumpolar dataset consists of 1300 ice cores collected during 32 cruises over a period of 25 years. The analyses show that integrated sea ice chlorophyll a peaks in early spring and late austral summer, which is consistent with theories on light and nutrient limitation. The results indicate that on a circum-Antarctic scale, surface, internal and bottom sea ice layers contribute equally to integrated biomass, …
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, …
Isotopic Characterization Of Aerosol Organic Carbon Components Over The Eastern United States, A. S. Wozniak, James E. Bauer, Rebecca M. Dickhut, Li Xu, Ann P. Mcnichol
Isotopic Characterization Of Aerosol Organic Carbon Components Over The Eastern United States, A. S. Wozniak, James E. Bauer, Rebecca M. Dickhut, Li Xu, Ann P. Mcnichol
VIMS Articles
Carbon isotopic signatures (delta C-13, Delta C-14) of aerosol particulate matter total organic carbon (TOC) and operationally defined organic carbon (OC) components were measured in samples from two background sites in the eastern U. S. TOC and water-soluble OC (WSOC) delta C-13 values (-27 to -24 parts per thousand) indicated predominantly terrestrial C-3 plant and fossil derived sources. Total solvent extracts (TSE) and their aliphatic, aromatic, and polar OC components were depleted in delta C-13 (-30 to -26 parts per thousand) relative to TOC and WSOC. Delta C-14 signatures of aerosol TOC and TSE (-476 to +25 parts per thousand) …