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Showing 1 to 14 of 14 for “"d15N"”.
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Nitrogen isotope variation in the environment: Implications for interpretation
… limits the use of N isotope natural abundance (d15N) in tracing the flow and fate of N in environments. Recent investigations have, however, revealed consistent and repeatable patterns of 15N in some ecosystem components. These patterns suggest that d15N may yet provide a tool to investigate and …
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Multi-isotope analysis and the reconstruction of prey species palaeomigrations and palaeoecology
… oxygen (d18O), carbon(d13C), nitrogen (d15N) and sulphur (d34S). Teeth (enamel and dentine) were sequentially-sampled in order to reconstruct time-series isotopic profiles at an intra- and inter-individual scale, allowing an assessment of the applicability of these methods to …
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Veränderung von Waldökosystemen aufgrund historischer Nutzung im Schwarzwald und in den Vogesen
… (wie pH-Wert, Basensättigung, C/N-Verhältnis und d15N) zu untersuchen und aufzuzeigen, wie die ehemalige Landnutzung diese Bodenparameter verändert sowie auf die Artenzusammensetzung und die Struktur der Waldbestände eingewirkt hat. <br>Hierfür wurden in fünf Untersuchungsgebieten im Schwarzwald …
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Assessing Thule Inuit impacts on High Arctic lakes and ponds : a paleolimnological approach
… assemblages coinciding with 1.5 - 2‰ shifts in d15N, during the period of Thule occupation (ca. 1000 – 1670 AD). Increases in the relative abundance of Amphora ovalis, indicate nutrient concentrations above average for the High Arctic. Elevated levels of nitrogen and phosphorus were observed in …
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Characterization of Mercury Transport and Fate in the Truckee River, NV, USA
… and Hg concentrations with the reach above, fish d15N and d13C varied. Below SBC all sites were impacted most notably in nitrogen, phosphorous, sulfate, and Hg concentrations that increased in all abiotic and biotic components. The latter reach varied Hg concentrations by components. Derby Dam is …
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How availability and quality of nectar and honeydew shape an Australian rainforest ant community
… from the study site. Nitrogen isotope ratios (d15N) of ants were not correlated with those of plant foliage from which the ants were collected. Instead, d15N may represent a powerful indicator of trophic position of omnivorous ants like in other foodweb studies, suggesting that members of the …
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The Use of Biomarker and Stable Isotope Analyses in Palaeopedology / Reconstruction of Middle and Late Quaternary Environmental and Climate History, with examples from Mt. Kilimanjaro, NE Siberia and NE Argentina
… stable carbon and nitrogen isotopes (d13C and d15N) in bulk soil organic matter (SOM) and on compound-specific isotope analysis (CSIA) of n-alkanes. The respective methods were partly optimized and then applied in multi-proxy analytical approaches to three selected palaeosol records, …
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Soil-plant dynamics of water, nitrogen and sulfur: A study on indigenous and exotic tree species in Munessa Forest, Ethiopia
… soil N and low natural-abundance d15N indicated an intense, conservative N cycling in the upper 60 cm, which was also evenly exploited by the roots of P. falcatus. Nitrogen uptake by E. globulus was concentrated in the deeper layers. A preferential stabilization of N was observed …
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Organic geochemical biosignatures in alkaline Hydrothermal ecosystems
… organic material and have end-member d15N values near 0 0/00, suggesting active nitrogen fixation is occurring.Biomass and lipids from Yellowstone hot springs also showed surprising enrichments in 13C. The common factor is high pH; unusual 13C enrichment may be common in alkaline …
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Holocene guano influences on eutrophication and lacustrine ecology at Kettle Lake, North Dakota
… are based on environmental changes reflected in d15N, I create a model to understand diagenetic changes in the sediment record. I use this “𝛿15N diagenesis model” to assess the degree of diagenetic change from remineralization in the sediment and then correct the original 𝛿15N record accordingly. …
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Hydrogeologie, Hydrogeochemie und Isotopie der Grund- und Grubenwässer im Einzugsgebiet des Burgfeyer Stollens bei Mechernich/Eifel
… environmental isotopes (d34S, d13C, d2H, d18O, d15N, 3H) and trace gases (CFC) of the upper and middle bunter sandstone groundwaters and of the mine waters have been performed in order derive a genetic model for the outflow waters of the Burgfeyer Stollen and identify the main chemical and …
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Composição da matéria orgânica no gradiente estuarino da Baía de Sepetiba/RJ
… marcadores elementares (C/N), isotópicos (d13C e d15N) e moleculares (lignina, esteróis e hidrocarbonetos) em amostras de sedimento e de material particulado em suspensão, sendo que neste último compartimento só foi possível a análise da composição elementar e isotópica da matéria orgânica. Os …
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The Potential of Bulk and Amino-Acid Specific Isotope Ratio Mass Spectrometry of Human Hair in Forensic and Clinical Applications
… was used to analyze bulk isotope ratio of d13C, d15N and d34S values of human hair. Finally, we have applied LC-IRMS to measure amino acid in 20 different females from Jordan between the ages of 17 and 50 years. The preliminary studies suggest that for a relatively small sample size of 20 …
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Positive and negative dynamics of plant-plant interactions along environmental gradients: Effects at individual and community level
… auftraten. So konnten wir die Abnahme der d15N Werte mit abnehmender N-Versorgung und zunehmender Artenzahl, die unserem Wissen nach bisher ausschließlich in Feldversuchen nachgewiesen wurde, in Mikrokosmen feststellen. Ebenso konnten wir zum Feld vergleichbare positive Effekte zunehmender …