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Showing 1 to 13 of 13 for “"Marine productivity"”.
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POPULATION DYNAMICS AND GEOCHEMISTRY OF BENTHIC AND PLANKTONIC FORAMINIFERA TO INTERPRET THE PALEOCEANOGRAPHIC CHANGES ACROSS THE CENOMANIAN-TURONIAN OCEANIC ANOXIC EVENT 2 AT LOW AND HIGH LATITUDES
… tolerant of high organic fluxes, indicating high marine productivity preceding the OAE 2. At low latitudes, a stratified water column indicating meso-oligotrophic regimes and low organic fluxes at the seafloor have been observed. A decrease in ΔpH in surface waters supports enhanced volcanic …
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An investigation of basin-scale controls on upper ocean export and remineralization
… of POC were examined across large gradients in productivity, upwelling, community structure, and dissolved oxygen in the southeastern tropical Pacific Ocean. Although low oxygen zones are traditionally thought to have decreased POC flux attenuation relative to other regions of the global ocean …
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Microbial cycling of marine high molecular weight dissolved organic matter
… mediating biogeochemical cycles in the ocean. Marine dissolved organic matter (DOM) – a reservoir of organic solutes and colloids derived from plankton is a major source of carbon, nutrients, and energy to microbial communities. The biological transformation and remineralization of DOM sustains …
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An investigation of basin-scale controls on upper ocean export and remineralization
… of POC were examined across large gradients in productivity, upwelling, community structure, and dissolved oxygen in the southeastern tropical Pacific Ocean. Although low oxygen zones are traditionally thought to have decreased POC flux attenuation relative to other regions of the global ocean …
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Microbial cycling of marine high molecular weight dissolved organic matter
… mediating biogeochemical cycles in the ocean. Marine dissolved organic matter (DOM) - a reservoir of organic solutes and colloids derived from plankton is a major source of carbon, nutrients, and energy to microbial communities. The biological transformation and remineralization of DOM sustains …
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Greenlandic ice archives of North Atlantic Common Era climate
… changes, illuminating a 10 ± 7% decline in marine productivity over the Industrialera. I next present a new climate record from a previously-unexplored coastal ice cap in west-central Greenland. Using a physically-constrained ice cap flowline inversion model, I identify marked …
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Latitudinal variation in plankton size spectra along the Atlantic Ocean
… rates and pathways of material transfer in the marine pelagic food web, and consequently the oceanic carbon cycle. The transfer of energy between trophic levels can be inferred from regular patterns in population size structure, where plots of abundance within size classes, also known as …
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N2 fixation by subsurface populations of Trichodesmium : an important source of new nitrogen to the North Atlantic Ocean
… is an important contributor to the marine nitrogen (N) and carbon (C) cycles. The extent to which Trichodesmium dinitrogen (N2) fixation contributes to the marine N cycle has been modeled based on abundance data and rate estimates from surface populations. However, recent data show …
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Physical controls on spring bloom dynamics in the Irminger Basin, North Atlantic
… cruises to the region carried out under the UK Marine Productivity programme. This data set is extended with six years of SeaWiFS satellite chlorophyll-a concentration (chl-a) data, together with the corresponding model net heat flux (NCEP reanalysis) and satellite measured wind speed …
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Iron limitation and the role of siderophores in marine Synechococcus
Marine cyanobacteria in the genus Synechococcus are widely distributed and contribute significantly to global primary productivity. In many parts of the ocean their growth is limited by a lack of iron, an essential nutrient that is virtually insoluble in seawater. To overcome this, Synechococcus …
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Exploring the Spatial Distribution of Marine Nitrogen Fixation Through Statistical Modeling, High-Resolution Observations and Molecular Level Characterization
<p>Marine productivity is limited by nitrogen in a large portion of the global ocean. Marine nitrogen fixation, catalyzed by a select group of microorganisms called diazotrophs, converts nitrogen gas (N2) into bioavailable nitrogen that can support the growth of marine phytoplankton. By supplying …
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The relationship between iron and nitrogen fixation in Trichodesmium spp.
… in situ, the importance of Fe to the marine N cycle.