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Fertilizer nitrogen isotope signatures
Isotopes in Environmental and Health Studies, 2007There has been considerable recent interest in the potential application of nitrogen isotope analysis in discriminating between organically and conventionally grown crops. A prerequisite of this approach is that there is a difference in the nitrogen isotope compositions of the fertilizers used in organic and conventional agriculture.
Bateman, Alison S., Kelly, Simon D.
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Nitrogen Isotopes in the Ocean [PDF]
, 2019 This article outlines the isotope systematics of processes in the ocean nitrogen (N) cycle and their impact on the isotopic compositions of the major N forms, with an eye toward how the N isotopes may record current N fluxes and past changes.
Sigman, Daniel M, Fripiat, François
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Anomalous Nitrogen Isotope Ratio in Comets
Science, 2003High-resolution spectra of the CN B 2 ∑ + – X 2 ∑ + (0,0) band at 390 nanometers yield isotopic ratios for comets C/1995 O1 (Hale-Bopp) and C/2000 WM1 (LINEAR) as follows: 165 ± 40 and 115 ± 20 for 12
Arpigny, Claude +7 more
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Mercury and Stable Isotopes of Carbon and Nitrogen in Mink
Environmental Toxicology and Chemistry, 2007Abstract Total Hg concentrations and values of stable isotopes (δ15N, δ13C) in tissues of mink (Mustela vison) captured in Rhode Island (USA) during winters of 1999 to 2004 were statistically distinct based on location. Mink captured in salt marsh environments (salt marsh group mink [SMGM]) had significantly lower mean Hg concentrations ...
James L, Lake +4 more
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Isotopic Analysis of Dissolved Organic Nitrogen in Soils
Analytical Chemistry, 2010Determination of the isotopic signature of dissolved organic nitrogen (DON) is important to assess its dynamics in terrestrial ecosystems. Analysis of (15)N-DON, however, has been hindered by the lack of simple, reliable, and established methods. We evaluate three off-line techniques for measuring the (15)N signature of DON in the presence of inorganic
Ros, G.H. +2 more
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Nitrogen and Oxygen Isotopic Studies of the Marine Nitrogen Cycle
Annual Review of Marine Science, 2016The marine nitrogen cycle is a complex web of microbially mediated reactions that control the inventory, distribution, and speciation of nitrogen in the marine environment. Because nitrogen is a major nutrient that is required by all life, its availability can control biological productivity and ecosystem structure in both surface and deep-ocean ...
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Stable Carbon and Nitrogen Isotopic
Aquatic Geochemistry, 2004The perennially ice-covered lakes in the McMurdo Dry Valleys, Antarctica, are part of the coldest and driest ecosystem on earth. To understand lacustrine carbon and nitrogen cycling in this end-member ecosystem, and to define paleolimnological proxies for ice-covered lakes, we measured the stable carbon and nitrogen isotopic composition of particulate ...
Jennifer Lawson +4 more
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Nitrogen isotopes in the Allende meteorite
Earth and Planetary Science Letters, 1981Nitrogen in the Allende meteorite consists of at least two components, partially resolvable in a stepwise heating experiment. L-nitrogen, released below 1000 C, has a low delta N-15 (-60 to -90 per mil), and is associated with neon-A and CCF-xenon and may reside in a carbonaceous carrier.
Mark H. Thiemens, Robert N. Clayton
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Isotopic Variability of Nitrogen in Lunar Regolith
Science, 2001Hashizume et al . ([1][1]) claim that the distribution and isotopic composition of nitrogen in the lunar regolith can be explained by a two-component mixing model. Their report, however, fails to discuss the bulk of existing relevant data—data that show unequivocally that the conclusions in ([1 ...
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Nitrogen isotopes in the solar system
Geochimica et Cosmochimica Acta, 1982Measurements of the isotopic composition of nitrogen in the solar system are summarized. We show that the 30% change, during the last 3 to 4 billion years, of 15N14N in solar-wind-bearing lunar soils and breccias probably does not reflect changes in this ratio at the solar surface.
Johannes Geiss, Peter Bochsler
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