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Interannual variation in stable carbon and nitrogen isotope biogeochemistry of the Mattaponi River, Virginia
Interannual variation stable carbon nitrogen isotope biogeochemistry Mattaponi River Virginia
2014/5/5
Seasonal and interannual variation of the stable carbon (C) and nitrogen (N) isotope composition of suspended particulate organic matter (POM) was measured in the brackish and tidal freshwater regions...
Probing the microenvironment of freshwater sediment macrofauna: Implications of deposit-feeding and bioirrigation for nitrogen cycling
freshwater sediment macrofauna bioirrigation for nitrogen cycling
2014/5/5
The effect of sediment-dwelling macrofauna on nitrifying bacteria was investigated by direct probing in their
overlapping habitat, i.e., the upper few millimeters of freshwater sediments. Microsensor...
The influence of nitrogen limitation on d15N and carbon : nitrogen ratios in sediments from sockeye salmon nursery lakes in British Columbia, Canada
nitrogen limitation on d15N and carbon nitrogen ratios in sediments sockeye salmon nursery lakes British Columbia Canada
2014/5/5
Carbon (C) and nitrogen (N) elemental and nitrogen isotopic ratios were determined for bulk organic matter in surface sediments of 11 sockeye salmon (Onchorynchus nerka) nursery lakes in British Colum...
Phytoplankton trapped within seagrass (Posidonia oceanica) sediments are a nitrogen source: An in situ isotope labeling experiment
Phytoplankton trapped within seagrass sediments nitrogen source: An in situ isotope labeling experiment
2014/5/4
We examined the retention of nitrogen associated with sedimented planktonic material trapped within a Mediterranean seagrass (Posidonia oceanica) meadow with the use of 15N-enriched algal material inj...
Nitrogen sources and cycling in the San Francisco Bay Estuary: A nitrate dual isotopic composition approach
Nitrogen sources cycling San Francisco Bay Estuary nitrate dual isotopic composition
2014/5/4
We used the dual isotopic composition of nitrate (δ15N and δ18O) within the estuarine system of San Francisco (SF) Bay, California, to explore the utility of this approach for tracing sources and cycl...
Contributions of carbon and nitrogen from the Andes Mountains to the Amazon River: Evidence from an elevational gradient of soils, plants, and river material
carbon and nitrogen Andes Mountains Amazon River elevational gradient of soils plants river material
2014/5/9
We determined the carbon (C) and nitrogen (N) elemental and stable isotopic composition of riverine and terrestrial organic matter (OM), as well as the concentration of dissolved organic C (DOC), δ15N...
Role of wetlands and developed land use on dissolved organic nitrogen concentrations and DON/TDN in northeastern U.S. rivers and streams
Role of wetlands developed land dissolved organic nitrogen concentrations DON/TDN northeastern U.S. rivers and streams
2014/5/19
Previous studies have shown that watersheds with significant human development (i.e., urban and agricultural land use) generally have higher concentrations and fluxes of dissolved inorganic nitrogen (...
Benthic nitrogen fluxes along a depth gradient in a microtidal fjord: The role of denitrification and microphytobenthos
Benthic nitrogen fluxes depth gradient microtidal fjord denitrification microphytobenthos
2014/5/19
In littoral sediments, microphytobenthic (MPB) nitrogen assimilation often exceeds nitrogen removal by denitrification, partly because MPB activity suppresses denitrification. Little is known about th...
Tissue carbon, nitrogen, and sulfur stable isotope turnover in transplanted Bathymodiolus childressi mussels: Relation to growth and physiological condition
Tissue carbon nitrogen sulfur stable isotope turnover transplanted Bathymodiolus childressi mussels growth and physiological condition
2014/5/19
The growth and physiological condition of the methanotrophic hydrocarbon seep mussel Bathymodiolus childressi reflects the habitat quality of the sites it occupies on the seafloor of the upper Louisia...
Seasonal variation of the d13C and d15N of particulate and dissolved carbon and nitrogen in Lake Lugano: Constraints on biogeochemical cycling in a eutrophic lake
Seasonal variation d13C and d15N particulate and dissolved carbon and nitrogen Lake Lugano biogeochemical cycling a eutrophic lake
2014/5/14
We determined the δ13C and δ15N of water-column particulate organic matter (POM), dissolved inorganic carbon, and nitrate, together with water chemistry and phytoplankton biomass and species compositi...
Evidence for terrigenous dissolved organic nitrogen in the Arctic deep sea
Arctic deep sea terrigenous dissolved organic nitrogen
2014/5/14
To trace the fate of terrigenous dissolved organic nitrogen (DON) in the Arctic Ocean, principal-components
analyses (PCA) was used on a data set of 13 amino acids released via hydrolyses from a tota...
The effect of water velocity on stable carbon and nitrogen isotope signatures of periphyton
water velocity stable carbon nitrogen isotope signatures
2014/5/22
Water movement affects carbon and nitrogen isotopic signatures of algae, possibly through effects on boundarylayer thickness. We describe a laboratory experiment carried out in artificial streams, whi...
Iron requirements for dinitrogen- and ammonium-supported growth in cultures of Trichodesmium (IMS 101): Comparison with nitrogen fixation rates and iron:carbon ratios of field populations
Iron requirements nitrogen- and ammonium-supported growth cultures of Trichodesmium nitrogen fixation rates and iron field populations
2014/5/21
We quantified the relationships among the specific growth rate, intracellular iron content, and steady state iron uptake rate for cultures of the marine diazotrophic cyanobacterium Trichodesmium (IMS ...
Predicting the response of Gulf of Mexico hypoxia to variations in Mississippi River nitrogen load
Gulf of Mexico hypoxia Mississippi River nitrogen load
2014/5/20
The effects of nutrient loading from the Mississippi River basin on the areal extent of hypoxia in the northern Gulf of Mexico were examined using a novel application of a dissolved oxygen model for a...
Relationship of nitrogen isotope fractionation to phytoplankton size and iron availability during the Southern Ocean Iron RElease Experiment (SOIREE)
nitrogen isotope fractionation phytoplankton size iron availability the Southern Ocean Iron RElease
2014/5/20
The 15N composition of sediments has been used as a proxy for nitrate utilization in surface waters to assess the role of Southern Ocean export production in glacial/interglacial changes in atmospheri...