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Stable isotopes of carbon and nitrogen in soil ecological studies
Biology Bulletin, 2007The development of stable isotope techniques is one of the main methodological advances in ecology of the last decades of the 20th century. Many biogeochemical processes are accompanied by changes in the ratio between stable isotopes of carbon and nitrogen (12C/13C and 14N/15N), which allows different ecosystem components and different ecosystems to be
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Primary Consumer Stable Nitrogen Isotopes as Indicators of Nutrient Source
Environmental Science & Technology, 2005Non-point source loading of nitrogen and phosphorus is a primary cause of eutrophication of inland waters, although the diffuse and variable nature of nutrient inputs makes it difficult to trace and identify nutrient pathways. Stable nitrogen isotope values (delta15N) in aquatic biota are thought to reflect anthropogenic nutrient inputs, and they may ...
Zanden, M. J. Vander +3 more
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Effects of Preservation Method on Stable Carbon and Nitrogen Isotope Values
Physiological and Biochemical Zoology, 2008Some methods of tissue preservation have significant effects on values of stable isotopes of carbon (delta(13)C) and nitrogen (delta(15)N), but studies on this topic are scattered in the literature. The goals of this study were to (1) summarize the results from studies of preservation effects in the literature and (2) test the effects of four common ...
Lindy M, Barrow +2 more
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A novel tool for stable nitrogen isotope analysis in aqueous samples
Rapid Communications in Mass Spectrometry, 2016Rationale Bulk stable isotope analysis (BSIA) of dissolved matter (e.g. dissolved organic carbon, total nitrogen bound (TN b ), etc.) is of particular importance since this pool is a prime conduit in the cycling of N and C.
E. Federherr +9 more
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Stable carbon and nitrogen isotope analysis of avian uric acid
Rapid Communications in Mass Spectrometry, 2008Abstract We report results obtained using a new technique developed to measure the stable‐isotope composition of uric acid isolated from bird excreta (guano). Results from a diet‐switch feeding trial using zebra finches suggest that the δ 13 C of uric ...
Bird, Michael I. +3 more
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USING STABLE ISOTOPES TO MONITOR ANTHROPOGENIC NITROGEN INPUTS TO ESTUARIES
Ecological Applications, 2008Use of stable nitrogen isotope ratios is one method that has been proposed to indicate anthropogenic nutrient enrichment in estuarine systems. However, the role of stable isotopes as a tool in long-term ecosystem monitoring has not been fully developed.
Charles T Roman
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Tracing the Influence of Sewage Nitrogen in a Coastal Ecosystem Using Stable Nitrogen Isotopes
AMBIO: A Journal of the Human Environment, 2005This paper reviews the use of stable nitrogen isotopes (delta15N) to delineate the influence of sewage nitrogen (N) in coastal ecosystems, drawing extensively on the case of Himmerfjärden, a Baltic Sea bay that receives 15N-enriched tertiary treated sewage that is discharged mainly as dissolved inorganic N (DIN).
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Model of Nitrogen Source Allocations and Transformations Using Stable Nitrogen Isotopes
World Environmental and Water Resources Congress 2013, 2013Stream restoration for water quality and nutrient management relies on effective assessment methods that measure the before-and-after improvement of water quality, or lack thereof, from implementation. We present a water quality and nutrient modeling tool for potential use in such applications.
W. I. Ford, J. F. Fox
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Labelling Compounds with the Stable Isotopes of Nitrogen and Oxygen
2011In this chapter we consider the methods that have been used to introduce the stable isotopes of nitrogen and oxygen into organic compounds. These isotopes have played an important role both in the study of organic reaction mechanisms and in biosynthesis.
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Fractionation of nitrogen stable isotopes by ion exchange chromatography
Journal of Radioanalytical and Nuclear Chemistry, 2003The ion exchange chromatography displacement technique was used for the enrichment of 15N. The runs were conducted in laboratory and bench scales using two systems of columns filled with Wofatit KPS ion exchange resin (medium porosity type). Ammonia NH4+/NH3 aq. was chosen as the isotopic exchange system.
Aguilera Y +4 more
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