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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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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 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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Nitrogen Isotopes in Palaeolimnology
2002Nitrogen is a small but essential constituent of all organisms and as such can be regarded as a key nutrient. Together with phosphorous and silicon, it is commonly viewed as one of the nutrients that ultimately limit organic productivity. Indeed, in many lakes, N is probably the limiting nutrient.
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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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Geochimica et Cosmochimica Acta, 2013
Abstract The 15 N/ 14 N isotopic ratio of marine particulate organic matter usually increases as a consequence of preferential 14 N-remineralization (ammonification) during decay in the oxic water-column and at the oxic seafloor. However, a fractionation factor 15 e of sediment ammonification in natural environments has not been determined yet ...
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Abstract The 15 N/ 14 N isotopic ratio of marine particulate organic matter usually increases as a consequence of preferential 14 N-remineralization (ammonification) during decay in the oxic water-column and at the oxic seafloor. However, a fractionation factor 15 e of sediment ammonification in natural environments has not been determined yet ...
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