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Showing 1 to 11 of 11 for “"Marine nitrogen"”.
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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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Mechanistic models of oceanic nitrogen fixation
Oceanic nitrogen fixation and biogeochemical interactions between the nitrogen, phosphorus and iron cycles have important implications for the control of primary production and carbon storage in the ocean. The biological process of nitrogen fixation is thought to be particularly important where the …
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Protein regulation in Trichodesmium and other marine bacteria: observational and interpretive biomarkers of biogeochemical processes
Marine microbes play key roles in global biogeochemistry by mediating chemical transformations and linking nutrient cycles to one another. A major goal in oceanography is to predict the activity of marine microbes across disparate ocean ecosystems. Towards this end, molecular biomarkers are …
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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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FLOW INJECTION INSTRUMENTATION FOR THE IN SITU MONITORING OF NUTRIENTS IN SEA WATER
… waters. Chapter One describes the role of nitrogen in the global and marine nitrogen cycles and provides an overview of laboratory and in situ methods for its determination. Chapter Two describes the key parameters for a field instrument and culminates with the overall design specification …
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Marine Deoxygenation Predates the End-Triassic Mass Extinction Within the Equatorial Panthalassa and its Influence on Marine Ecosystems Before the Biotic Crisis
… of both CAMP and the ETME. Here, we present nitrogen isotope (δ15N) and iron speciation data from a sedimentary succession located in Grotto Creek, Alaska in order track changes in the marine nitrogen cycle and redox across the upper Norian Stage of the Triassic through lower Hettangain Stage …
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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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History, Ecology and Restoration Potential of Salmonid Fishes in the Umpqua River, Oregon
… lethal limits in months of July and August. Marine nitrogen (δN15) signals were highest in the Main Umpqua River, and may be compounded by agriculture, however further studies are necessary to determine agricultural influence. Restoration recommendations for salmonids in the Umpqua River …
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History, Ecology and Restoration Potential of Salmonid Fishes in the Umpqua River, Oregon
… lethal limits in months of July and August. Marine nitrogen (δN15) signals were highest in the Main Umpqua River, and may be compounded by agriculture, however further studies are necessary to determine agricultural influence. Restoration recommendations for salmonids in the Umpqua River …
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The Marine Cyanate Cycle
<p>Cyanate (OCN-) is a reduced nitrogen compound with the potential to serve as a nitrogen and carbon source for marine microbes. Evidence from genomes and culture studies indicated that several marine cyanobacterial groups, including representatives of the globally important genera Synechococcus …
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Controls on nitrogen fixation and nitrogen release in a diazotrophic endosymbiont of shipworms
Nitrogen fixation is an ecologically important microbial process that can contribute bioavailable combined N to habitats low in N. Shipworms, or wood-boring bivalves, host N2-fixing and cellulolytic symbiotic bacteria in gill bacteriocytes, which have been implicated as a necessary adaptation to an …