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Journal articles on the topic 'Carbon Isotopes; Isotopic analysis; Organic residues'

Author: Grafiati

Published: 4 June 2021

Last updated: 5 February 2022

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1

Witt, Bradd. "Century-scale environmental reconstruction by using stable carbon isotopes: just one method from the big bag of tricks." Australian Journal of Botany 50, no. 4 (2002): 441. http://dx.doi.org/10.1071/bt02006.

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The field of 'historical ecology' is coming to maturity at a time when we, in Australia, are reflecting on our relationship with, and place in, the land. After an essentially ahistorical approach to land use we are now attempting to place land management into the context of environmental change since and immediately preceding Western European settlement. This volume reflects an emerging concern that, collectively, non-indigenous Australians have no 'environmental history'. One component of 'living in' rather than 'battling against' the land is developing a sense of our history. Without an oral

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Magioncalda, Roberto, Christian Dupuis, Dominique Blamart, et al. "L'excursion isotopique du carbone organique (delta 13 C org ) dans les paleoenvironnements continentaux de l'intervalle Paleocene/Eocene de Varangeville (Haute-Normandie)." Bulletin de la Société Géologique de France 172, no. 3 (2001): 349–58. http://dx.doi.org/10.2113/172.3.349.

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Abstract The late Palaeocene carbon isotope excursion (C.I.E.) is often regarded as the best means of correlating marine and continental deposits. The few isotopic studies carried out in continental environments were based on pedogenic carbonate [Koch et al., 1992], or on organic matter. Sinha [1997] took up this subject starting from the outcrops on the coast of the English Channel at Varangeville, where marine sequences biostratigraphically constrain the isotopic excursion. His work documents a negative delta 13 C org excursion value approximately -27 per mil PDB. The present work points out

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Hanke, U. M., L. Wacker, N. Haghipour, M. W. I. Schmidt, T. I. Eglinton, and C. P. McIntyre. "Comprehensive radiocarbon analysis of benzene polycarboxylic acids (BPCAs) derived from pyrogenic carbon in environmental samples." Radiocarbon 59, no. 4 (2017): 1103–16. http://dx.doi.org/10.1017/rdc.2017.44.

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ABSTRACTCompound-specific radiocarbon analysis (CSRA) of benzene polycarboxylic acids (BPCAs) yields molecular-level, source-specific information necessary to constrain isotopic signatures of pyrogenic carbon. However, the purification of individual BPCAs requires a multistep procedure that typically results in only microgram quantities of the target analyte(s). Such small samples are highly susceptible to contamination by extraneous carbon, which needs to be minimized and carefully accounted for in order to yield accurate results. Here, we undertook comprehensive characterization and quantifi

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Fuller, Mark E., Linnea Heraty, Charles W. Condee, et al. "Relating Carbon and Nitrogen Isotope Effects to Reaction Mechanisms during Aerobic or Anaerobic Degradation of RDX (Hexahydro-1,3,5-Trinitro-1,3,5-Triazine) by Pure Bacterial Cultures." Applied and Environmental Microbiology 82, no. 11 (2016): 3297–309. http://dx.doi.org/10.1128/aem.00073-16.

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ABSTRACTKinetic isotopic fractionation of carbon and nitrogen during RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) biodegradation was investigated with pure bacterial cultures under aerobic and anaerobic conditions. Relatively large bulk enrichments in15N were observed during biodegradation of RDX via anaerobic ring cleavage (ε15N = −12.7‰ ± 0.8‰) and anaerobic nitro reduction (ε15N = −9.9‰ ± 0.7‰), in comparison to smaller effects during biodegradation via aerobic denitration (ε15N = −2.4‰ ± 0.2‰).13C enrichment was negligible during aerobic RDX biodegradation (ε13C = −0.8‰ ± 0.5‰) but larger

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Ramnarine, R., C. Wagner-Riddle, K. E. Dunfield, and R. P. Voroney. "Contributions of carbonates to soil CO2 emissions." Canadian Journal of Soil Science 92, no. 4 (2012): 599–607. http://dx.doi.org/10.4141/cjss2011-025.

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Ramnarine, R., Wagner-Riddle, C., Dunfield, K. E. and Voroney, R. P. 2012. Contributions of carbonates to soil CO 2 emissions. Can. J. Soil Sci. 92: 599–607. Carbon dioxide (CO2) is released in soil as a by-product of microbial and root respiration, but soil carbonates may also be a source of CO2 emissions in calcareous soils. Global estimates of inorganic carbon range from 700 to 900 Pg as carbonates stored in soils, representing a significant potential source of CO2 to the atmosphere. While previous studies have focused on the total CO2 efflux from the soil, our goal was to identify the vari

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Barešić, Jadranka, Sanja Faivre, Andreja Sironić, et al. "The Potential of Tufa as a Tool for Paleoenvironmental Research—A Study of Tufa from the Zrmanja River Canyon, Croatia." Geosciences 11, no. 9 (2021): 376. http://dx.doi.org/10.3390/geosciences11090376.

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Tufa is a fresh-water surface calcium carbonate deposit precipitated at or near ambient temperature, and commonly contains the remains of macro- and microphytes. Many Holocene tufas are found along the Zrmanja River, Dalmatian karst, Croatia. In this work we present radiocarbon dating results of older tufa that was found for the first time at the Zrmanja River near the Village of Sanaderi. Tufa outcrops were observed at different levels, between the river bed and up to 26 m above its present level. Radiocarbon dating of the carbonate fraction revealed ages from modern, at the river bed, up to

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Choy, Kyungcheol, Ben A. Potter, Holly J. McKinney, Joshua D. Reuther, Shiway W. Wang, and Matthew J. Wooller. "Chemical profiling of ancient hearths reveals recurrent salmon use in Ice Age Beringia." Proceedings of the National Academy of Sciences 113, no. 35 (2016): 9757–62. http://dx.doi.org/10.1073/pnas.1606219113.

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Current approaches to reconstruct subsistence and dietary trends in ancient hunter-gatherer societies include stable isotope analyses, but these have focused on human remains, cooking pottery, and food residues, which are relatively rare in the archaeological record. In contrast, short-term hearths are more ubiquitous worldwide, and these features can provide valuable evidence for ancient subsistence practices, particularly when faunal remains are not preserved. To test the suitability of hearths for this purpose, we conducted multiple chemical analyses: stable carbon and nitrogen isotope anal

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Megens, Luc, Johannes Van Der Plicht, and Jan W. De Leeuw. "Molecular, Radioactive and Stable Carbon Isotope Characterization of Estuarine Particulate Organic Matter." Radiocarbon 40, no. 2 (1997): 985–90. http://dx.doi.org/10.1017/s0033822200018956.

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Organic matter in sediments and suspended matter is a complex mixture of constituents with different histories, sources and stabilities. To study these components in a suspended matter sample from the Ems-Dollard Estuary, we used combined molecular analysis with pyrolysis/gas chromatography/mass spectrometry and stable and radioactive carbon isotope analyses of the bulk and separated chemical fractions. Carbohydrates and proteins, ca. 50% of the total organic carbon (TOC), are much younger than the bulk sample and have a somewhat higher δ13C value. Lipids and the final residue are considerably

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Kayler, Z. E., M. Kaiser, A. Gessler, R. H. Ellerbrock та M. Sommer. "Application of δ<sup>13</sup>C and δ<sup>15</sup>N isotopic signatures of organic matter fractions sequentially separated from adjacent arable and forest soils to identify carbon stabilization mechanisms". Biogeosciences 8, № 10 (2011): 2895–906. http://dx.doi.org/10.5194/bg-8-2895-2011.

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Abstract. Identifying the chemical mechanisms behind soil carbon bound in organo-mineral complexes is necessary to determine the degree to which soil organic carbon is stabilized belowground. Analysis of δ13C and δ15N isotopic signatures of stabilized OM fractions along with soil mineral characteristics may yield important information about OM-mineral associations and their processing history. We anlayzed the δ13C and δ15N isotopic signatures from two organic matter (OM) fractions along with soil mineral proxies to identify the likely binding mechanisms involved. We analyzed OM fractions hypot

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Šoberl, Lucija, Andreja Žibrat Gašparič, Mihael Budja, and Richard P. Evershed. "Early herding practices revealed through organic residue analysis of pottery from the early Neolithic rock shelter of Mala Triglavca, Slovenia." Documenta Praehistorica 35 (December 31, 2008): 253–60. http://dx.doi.org/10.4312/dp.35.19.

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A collection of pottery from the early Neolithic site of Mala Triglavca was analysed with the aim of obtaining insights into vessel use and early animal domestication and husbandry practices in the Adriatic region. Total lipid extracts were submitted to gas chromatography (GC), GC-mass spectrometry (GC-MS) and GC-combustion-isotope ratio MS (GC-C-IRMS) in order to obtain molecular and stable carbon isotope signatures as the basis for determining the nature and origins of the residues. The extracts were dominated by degraded animal fats. The majority (70%) of the total lipid extracts displayed

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Šoberl, Lucija, Milena Horvat, Andreja Žibrat Gašparič, Marko Sraka, Richard Evershed, and Mihael Budja. "Neolithic and Eneolithic activities inferred from organic residue analysis of pottery from Mala Triglavca, Moverna vas and Ajdovska jama, Slovenia." Documenta Praehistorica 41 (December 30, 2014): 149–79. http://dx.doi.org/10.4312/dp.41.9.

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The research discussed in this paper focused on the analysis and identification of organic residues either preserved as visible or absorbed organic remains on Neolithic and Eneolithic pottery from various archaeological and geographical contexts. These are connected with various food preparation strategies and past human activities, i.e. cave burials in Ajdovska jama (food as a grave good/offering), the rock shelter at Mala Triglavca (meat and dairy animal husbandry practices) and Moverna vas, which had a long occupation sequence (complex farming and animal management). The preservation of bio

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Horiuchi, Akiko, Yoshiki Miyata, Nobuhiko Kamijo, Lucy Cramp, and Richard P. Evershed. "A Dietary Study of the Kamegaoka Culture Population during the Final Jomon Period, Japan, Using Stable Isotope and Lipid Analyses of Ceramic Residues." Radiocarbon 57, no. 4 (2015): 721–36. http://dx.doi.org/10.2458/azu_rc.57.18455.

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The Jomon culture is an ancient Japanese society that existed during approximately 14,000 to 400 BC and which is characterized by Jomon (cord pattern) pottery. To investigate the paleodiet of the people of northeastern Tohoku in Japan during the Final Jomon period (about 1000–400 BC), we studied three sites in Aomori Prefecture, the center of the Kamegaoka culture. The Fubinashi site is on the coast and was supported by a rich fishing culture. Imazu was a coastal salt-making site. Sugisawa is a mountainous inland site on the banks of a river. We determined the 14C ages of the interior and exte

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Sánchez P., Maureen, Sally P. Horn, and Chad Steven Lane. "Stable carbon and nitrogen isotope ratios of surface food residues in pre-Columbian ceramics from the southern Pacific of Costa Rica as evidence of prehistoric human diets." UNED Research Journal 11, no. 2 (2019): 89–97. http://dx.doi.org/10.22458/urj.v11i2.2121.

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Introduction: to understand and interpret the consumption of plants and animals by humans in the past requires the investigation of different lines of evidence. Identifiable macroscopic remains of plants and animals, for example seeds and bones, are frequently found at archaeological sites and provide key data on food resources. Their analysis is complemented by the study of pollen grains or phytoliths of cultivated plants within archaeological horizons or in sediment cores recovered from lakes and wetlands near archaeological sites. Another important source of information on human diets in th

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Miljević, Nada, and Dušan Golobočanin. "Potential Use of Environmental Isotopes in Pollutant Migration Studies." Archives of Industrial Hygiene and Toxicology 58, no. 2 (2007): 251–62. http://dx.doi.org/10.2478/v10004-007-0015-5.

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Potential Use of Environmental Isotopes in Pollutant Migration StudiesThis article presents the use of natural abundance stable isotope (hydrogen, carbon, nitrogen, oxygen, chlorine) analysis data as a tool for providing important information about the origin of contaminants, the contribution of different sources to a multi-source plume, characterisation of their complex transport (rate and mechanisms) and for evaluating the success of contaminated site remediation. Isotopic signatures of contaminants are useful tracers of their sources, while isotopic fractionation can be used to quantitative

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Vimont, Isaac J., Jocelyn C. Turnbull, Vasilii V. Petrenko та ін. "An improved estimate for the <i>δ</i><sup>13</sup>C and <i>δ</i><sup>18</sup>O signatures of carbon monoxide produced from atmospheric oxidation of volatile organic compounds". Atmospheric Chemistry and Physics 19, № 13 (2019): 8547–62. http://dx.doi.org/10.5194/acp-19-8547-2019.

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Abstract. Atmospheric carbon monoxide (CO) is a key player in global atmospheric chemistry and a regulated pollutant in urban areas. Oxidation of volatile organic compounds (VOCs) is an important component of the global CO budget and has also been hypothesized to contribute substantially to the summertime urban CO budget. In principle, stable isotopic analysis of CO could constrain the magnitude of this source. However, the isotopic signature of VOC-produced CO has not been well quantified, especially for the oxygen isotopes. We performed measurements of CO stable isotopes on air samples from

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Gu, Binhe, Donald M. Schell, and Vera Alexander. "Stable Carbon and Nitrogen Isotopic Analysis of the Plankton Food Web in a Subarctic Lake." Canadian Journal of Fisheries and Aquatic Sciences 51, no. 6 (1994): 1338–44. http://dx.doi.org/10.1139/f94-133.

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Carbon and nitrogen stable isotopes (δ13C and δ15N) were used to track energy flow and nutrient cycling pathways in the plankton food web of a subarctic Alaskan lake. Results indicated that planktonic primary production was the major energy source fueling the zooplankton community. In spring, δ15N of Daphnia was strongly influenced by atmospheric nitrogen derived from a N2-fixing blue-green algal bloom. In winter, δ13C evidence suggested that phytoplankton comprised a small fraction (~15%) of particulate organic matter (POM) in the water column, largely due to low primary productivity. The dis

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Litvin, Steven Y., and Michael P. Weinstein. "Multivariate analysis of stable-isotope ratios to infer movements and utilization of estuarine organic matter by juvenile weakfish (Cynoscion regalis)." Canadian Journal of Fisheries and Aquatic Sciences 61, no. 10 (2004): 1851–61. http://dx.doi.org/10.1139/f04-121.

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Canonical discriminant analysis of the natural carbon, nitrogen, and sulfur stable isotopes in tissues of young weakfish (Cynoscion regalis) captured in Delaware Bay was used to infer movements of juveniles and to estimate the utilization of estuarine organic matter in this marine transient species. Two gradients emerged in the data. The first was associated with contributions from tidal salt marsh macrophytes, Spartina alterniflora in the polyhaline lower Bay and Phragmites australis in the brackish upper Bay. The second was associated with the expected change in phytoplankton carbon-isotope

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Currie, L. A., J. E. Dibb, G. A. Klouda, et al. "The Pursuit of Isotopic and Molecular Fire Tracers in the Polar Atmosphere and Cryosphere." Radiocarbon 40, no. 1 (1997): 381–90. http://dx.doi.org/10.1017/s0033822200018269.

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We present an overview of recent multidisciplinary, multi-institutional efforts to identify and date major sources of combustion aerosol in the current and paleoatmospheres. The work was stimulated, in part, by an atmospheric particle “sample of opportunity” collected at Summit, Greenland in August 1994, that bore the 14C imprint of biomass burning. During the summer field seasons of 1995 and 1996, we collected air filter, surface snow and snowpit samples to investigate chemical and isotopic evidence of combustion particles that had been transported from distant fires. Among the chemical trace

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Jessberger, Elmar K., and Jochen Kissel. "Chemical Properties of Cometary Dust and A Note on Carbon Isotopes." International Astronomical Union Colloquium 116, no. 2 (1991): 1075–92. http://dx.doi.org/10.1017/s0252921100012823.

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AbstractOn board the space probes Giotto and VEGAs and 2, which were sent through the coma of comet Halley, were the mass spectrometers PIA and PUMAs 1 and 2 for the in situ analysis of cometary dust. This paper summarizes the results obtained up to now, about four years after the flybys. It is sought to make the reader aware of the significance, but also of the limitations, of these unprecedented data gathered within a few hundred seconds with an innovative instrument about 1.5 x 108 km away from Earth. The first part of this paper shows how the bulk properties of the dust are derived—the mai

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Rustiah, Wa Ode, Alfian Noor, Maming, and Muhammad Lukman. "ANALYSIS OF THE SEASONAL IMPACT ON ISOTOPIC BASELINES OF DISSOLVED INORGANIC CARBON (DIC) IN COASTAL WATERS SPERMONDE, SOUTH SULAWESI." Jurnal Ilmu dan Teknologi Kelautan Tropis 11, no. 1 (2019): 141–49. http://dx.doi.org/10.29244/jitkt.v11i1.24778.

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Stable carbon isotopes have been commonly used as indicators for assessing environmental changes in aquatic ecosystems. They can be used to study the dynamics of organic matter as for understanding the overall functioning of the ecosystem, the connectivity of estuaries with terrestrial and marine coastal habitats. The objective of this study is determining the seasonal natural effects over isotopic (13C/12C) baselines in monitoring CO2 storage in dissolved inorganic materials in Spermonde waters on the west coast of South Sulawesi to some outermost island. The results show that the stable carb

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Watson, Elizabeth Burke, Alejandro Hinojosa-Corona, Johannes R. Krause, et al. "Lagoon Biogeochemical Processing is Reflected in Spatial Patterns of Sediment Stable Isotopic Ratios." Journal of Marine Science and Engineering 8, no. 11 (2020): 874. http://dx.doi.org/10.3390/jmse8110874.

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The spatial analysis of biota, particulate organic matter, and sediments for stable isotopes of carbon (δ13C), nitrogen (δ15N), and sulfur (δ34S) have proved useful for identifying patterns in productivity, nutrient pollution, and relationships between biological and physiochemical variables at the local and global scales. Yet such approaches are rarely applied to studies of lagoon or estuarine metabolism. Focusing on Bahía San Quintín, a heterotrophic seagrass-dominated lagoon on the Pacific coast of Baja California, México, we report on spatial patterns in surficial sediment CNS stable isoto

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Golubkov, Mikhail S., Vera N. Nikulina, Alexei V. Tiunov, and Sergey M. Golubkov. "Stable C and N Isotope Composition of Suspended Particulate Organic Matter in the Neva Estuary: The Role of Abiotic Factors, Productivity, and Phytoplankton Taxonomic Composition." Journal of Marine Science and Engineering 8, no. 12 (2020): 959. http://dx.doi.org/10.3390/jmse8120959.

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Knowledge of carbon and nitrogen isotopic ratios in organic matter and their changes is important when studying nutrient cycles in aquatic ecosystems. Relationships between δ13C and δ15N values of suspended particulate organic matter (POM), water temperature, salinity, pH, redox potential, chlorophyll a concentration, primary production, and biomasses of different taxonomic groups of phytoplankton in the Neva Estuary were statistically analyzed. We tested the hypothesis that the studied physicochemical and biogeochemical characteristics, as well as the species composition of phytoplankton and

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Niu, Yong, Hui Yu, Yuan Niu, et al. "Isotopic fractionation of particulate organic matter and its biogeochemical implication in the littoral zone of Lake Taihu, China." Water Science and Technology 76, no. 10 (2017): 2690–97. http://dx.doi.org/10.2166/wst.2017.439.

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Abstract Signatures of stable isotope ratios have previously been used to trace the source and transport of particulate organic matter (POM) in freshwater and marine ecosystems. In this study, water columns were collected at 22 sites in the littoral zone of Lake Taihu in 2014 to investigate the distribution and concentration of nutrients and the stable isotope signatures of POM, and their potential interrelation. Generally, mean concentration of nitrogen forms (NH4+-N) showed substantial variation, probably because they had received large amounts of wastewater from various local industrial ent

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Krasnova, Elizaveta A., Anna Yu Yurchenko, Anton G. Kalmykov, and Maria M. Fomina. "Isotopic-geochemical peculiarities of distribution of gas hydrocarbons in the Bazhenov formation section (South part of the Western Siberia)." Georesursy 21, no. 2 (2019): 153–58. http://dx.doi.org/10.18599/grs.2019.2.153-158.

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In this work we describe the distribution of stable carbon isotopes in hydrocarbon gases from four wells located in the southern and central parts of the Western Siberia. The main goal was to understand the influence of the lithological composition and geological settings on isotopic composition of gases and their formation. Two genetically different groups of hydrocarbon gases were identified based on the author’s research, as well as analysis of archival and literature materials on the isotope composition of hydrocarbons. We estimated the close relationship between the main factors of the mi

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Nadeu, E., A. A. Berhe, J. de Vente, and C. Boix-Fayos. "Erosion, deposition and replacement of soil organic carbon in Mediterranean catchments: a geomorphological, isotopic and land use change approach." Biogeosciences 9, no. 3 (2012): 1099–111. http://dx.doi.org/10.5194/bg-9-1099-2012.

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Abstract. Determination of whether soil erosion can constitute a net terrestrial carbon dioxide (CO2) sink continues to suffer from lack of sufficient focused studies and field data. Two of the major gaps in our understanding of the erosion induced terrestrial carbon sink issue include rate of eroded soil organic carbon replacement by production of new photosynthate and stability of eroded organic carbon (OC) post deposition. Here we examined the effect of erosion processes and land use change on the stock, type, and stability of OC in two medium-sized subcatchments (18 and 50 ha in size) in S

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Nadeu, E., A. A. Berhe, J. de Vente, and C. Boix-Fayos. "Erosion, deposition and replacement of soil organic carbon in Mediterranean catchments: a geomorphological, isotopic and land use change approach." Biogeosciences Discussions 8, no. 4 (2011): 8351–82. http://dx.doi.org/10.5194/bgd-8-8351-2011.

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Abstract. The assessment of the net effect of soil erosion on the global carbon budget is still incomplete because of lack of enough focused studies and field data. Two of the major gaps on our understanding of the erosion induced terrestrial carbon sink issue include rate of eroded soil organic carbon (OC) replacement by production of new photosynthate and stability of eroded OC post deposition. Here we examine the effect of erosion processes and land use change on the stock, type and stability of OC in two medium-sized subcatchments (18 and 50 ha in size) in SE Spain. We analysed soil sample

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Schmittner, A., N. Gruber, A. C. Mix, R. M. Key, A. Tagliabue та T. K. Westberry. "Biology and air–sea gas exchange controls on the distribution of carbon isotope ratios (<i>δ</i><sup>13</sup>C) in the ocean". Biogeosciences Discussions 10, № 5 (2013): 8415–66. http://dx.doi.org/10.5194/bgd-10-8415-2013.

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Abstract. Analysis of observations and sensitivity experiments with a new three-dimensional global model of stable carbon isotope cycling elucidate the processes that control the distribution of δ13C in the contemporary and preindustrial ocean. Biological fractionation dominates the distribution of δ13CDIC of dissolved inorganic carbon (DIC) due to the sinking of isotopically light δ13C organic matter from the surface into the interior ocean. This process leads to low δ13CDIC values at dephs and in high latitude surface waters and high values in the upper ocean at low latitudes with maxima in

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Cawley, Kaelin M., Yan Ding, James Fourqurean, and Rudolf Jaffé. "Characterising the sources and fate of dissolved organic matter in Shark Bay, Australia: a preliminary study using optical properties and stable carbon isotopes." Marine and Freshwater Research 63, no. 11 (2012): 1098. http://dx.doi.org/10.1071/mf12028.

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Low latitude, seagrass-dominated coastal bays, such as Shark Bay, Australia, are potential sources of chromophoric dissolved organic matter (CDOM) to coastal regions. Dissolved organic matter (DOM) is known to influence aquatic nutrient dynamics, microbial community structure, and depth of light penetration in estuarine systems. Shark Bay is a sub-tropical ecosystem with limited freshwater inputs and restricted tidal flushing. As such, much of the DOM is expected to be seagrass-derived. However, combining excitation/emission fluorescence spectroscopy and parallel factor analysis (EEM-PARFAC) w

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Elshayeb, Monalisa, Michael D. MacKinnon, D. George Dixon, and Michael Power. "The Use of Carbon and Nitrogen Stable Isotope Analysis to Characterize Food Web Changes in Aquatic Systems for Reclamation of Oil Sands Process-Affected Materials." Water Quality Research Journal 44, no. 4 (2009): 313–22. http://dx.doi.org/10.2166/wqrj.2009.032.

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Abstract One strategy for reclamation of oil sands leases in northern Alberta is the construction of lakes and wetlands by capping oil sands process-affected material (OSPM) with water. To assess this approach, experimental sites containing a range of OSPM have been constructed to monitor the evolution of the resulting aquatic habitats. Stable isotopes of carbon and nitrogen were used to assess the effects of OSPM on aquatic food webs. Carbon and nitrogen isotopic signatures of sediment, dissolved inorganic and organic carbon, particulate organic matter, periphyton, plants, plankton, aquatic i

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Grocholska, Paulina, and Remigiusz Bąchor. "Trends in the Hydrogen−Deuterium Exchange at the Carbon Centers. Preparation of Internal Standards for Quantitative Analysis by LC-MS." Molecules 26, no. 10 (2021): 2989. http://dx.doi.org/10.3390/molecules26102989.

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The application of internal standards in quantitative and qualitative bioanalysis is a commonly used procedure. They are usually isotopically labeled analogs of the analyte, used in quantitative LC-MS analysis. Usually, 2H, 13C, 15N and 18O isotopes are used. The synthesis of deuterated isotopologues is relatively inexpensive, however, due to the isotopic effect of deuterium and the lack of isotopologue co-elution, usually they are not considered as good internal standards for LC-MS quantification. On the other hand, the preparation of 13C, 15N and 18O containing standards of drugs and their m

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Schmittner, A., N. Gruber, A. C. Mix, R. M. Key, A. Tagliabue та T. K. Westberry. "Biology and air–sea gas exchange controls on the distribution of carbon isotope ratios (δ<sup>13</sup>C) in the ocean". Biogeosciences 10, № 9 (2013): 5793–816. http://dx.doi.org/10.5194/bg-10-5793-2013.

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Abstract. Analysis of observations and sensitivity experiments with a new three-dimensional global model of stable carbon isotope cycling elucidate processes that control the distribution of δ13C of dissolved inorganic carbon (DIC) in the contemporary and preindustrial ocean. Biological fractionation and the sinking of isotopically light δ13C organic matter from the surface into the interior ocean leads to low δ13CDIC values at depths and in high latitude surface waters and high values in the upper ocean at low latitudes with maxima in the subtropics. Air–sea gas exchange has two effects. Firs

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de Lecea, Ander M., Rachel Cooper та Albertus J. Smit. "Identifying the drivers of the pelagic ecosystem of an oligotrophic bight (KwaZulu–Natal, South Africa) using stable isotopes (δ13C, δ15N) and C : N ratio analysis". Marine and Freshwater Research 67, № 11 (2016): 1750. http://dx.doi.org/10.1071/mf15256.

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The international literature highlights the importance of understanding the role and fate of terrestrial organic matter (OM) in the marine system, yet little is known about this on the oligotrophic east coast of South Africa. Within the Bight, three important processes make OM biologically available: (1) a topographically induced upwelling cell (north), (2) a Cyclonic Eddy (south), and (3) riverine input. We hypothesise that: (i) these OM sources differ substantially in their isotope ratios, and (ii) zooplankton at the inshore region has an isotope signature linked to localised fluvial fluxes.

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Bieleń, Wojciech, and Marek Janiga. "Spektrometria masowa i analiza izotopowa biomarkerów frakcji nasyconej." Nafta-Gaz 77, no. 8 (2021): 512–28. http://dx.doi.org/10.18668/ng.2021.08.02.

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GC-IRMS analysis extends and confirms (or not) the interpretation based on the results of GC-MS analyses. For example, it is very useful in determining the sedimentation environment of organic matter. GC-MS analysis of biomarkers and the results are reliable, but only GC-IRMS studies can confirm it. In this study, the origin of BNH (28,30-bisnorhopane from chemoautotrophic bacteria) and origin of higher carotenoids and their derivatives from Chlorobiaceae or Chromotiaceae bacteria were confirmed through isotopic analyzes. Biomarkers were analyzed using the GC-IRMS and EA-IRMS apparatus. The ob

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Jeffreys, R. M., E. H. Fisher, A. J. Gooday, K. E. Larkin, G. A. Wolff, and D. S. M. Billett. "The trophic and metabolic pathways of foraminifera in the Arabian Sea: evidence from cellular stable isotopes." Biogeosciences Discussions 11, no. 12 (2014): 18145–88. http://dx.doi.org/10.5194/bgd-11-18145-2014.

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Abstract. The Arabian Sea is a region of elevated productivity with the highest globally recorded fluxes of particulate organic matter (POM) to the deep ocean, providing an abundant food source for fauna at the seafloor. However, benthic communities are also strongly influenced by an intense oxygen minimum zone (OMZ), which impinges on the continental slope at bathyal depths. We compared the trophic ecology of foraminifera on the Oman and Pakistan margins of the Arabian Sea (140–3185 m water depth). Organic carbon concentrations of surficial sediments were higher on the Oman margin (3.32 ± 1.4

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Jeffreys, R. M., E. H. Fisher, A. J. Gooday, K. E. Larkin, D. S. M. Billett, and G. A. Wolff. "The trophic and metabolic pathways of foraminifera in the Arabian Sea: evidence from cellular stable isotopes." Biogeosciences 12, no. 6 (2015): 1781–97. http://dx.doi.org/10.5194/bg-12-1781-2015.

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Abstract. The Arabian Sea is a region of elevated productivity with the highest globally recorded fluxes of particulate organic matter (POM) to the deep ocean, providing an abundant food source for fauna at the seafloor. However, benthic communities are also strongly influenced by an intense oxygen minimum zone (OMZ), which impinges on the continental slope from 100 to 1000 m water depth. We compared the trophic ecology of foraminifera on the Oman and Pakistan margins of the Arabian Sea (140–3185 m water depth). These two margins are contrasting both in terms of the abundance of sedimentary or

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Iverach, Charlotte P., Sabrina Beckmann, Dioni I. Cendón, Mike Manefield, and Bryce F. J. Kelly. "Biogeochemical constraints on the origin of methane in an alluvial aquifer: evidence for the upward migration of methane from underlying coal measures." Biogeosciences 14, no. 1 (2017): 215–28. http://dx.doi.org/10.5194/bg-14-215-2017.

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Abstract. Geochemical and microbiological indicators of methane (CH4) production, oxidation and migration processes in groundwater are important to understand when attributing sources of gas. The processes controlling the natural occurrence of CH4 in groundwater must be understood, especially when considering the potential impacts of the global expansion of coal seam gas (CSG) production on groundwater quality and quantity. We use geochemical and microbiological data, along with measurements of CH4 isotopic composition (δ13C-CH4), to determine the processes acting upon CH4 in a freshwater allu

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Macko, Stephen A., Michael H. Engel, Vladimir Andrusevich, Gert Lubec, Tamsin C. O'Connell, and Robert E. M. Hedges. "Documenting the diet in ancient human populations through stable isotope analysis of hair." Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 354, no. 1379 (1999): 65–76. http://dx.doi.org/10.1098/rstb.1999.0360.

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Fundamental to the understanding of human history is the ability to make interpretations based on artifacts and other remains which are used to gather information about an ancient population. Sequestered in the organic matrices of these remains can be information, for example, concerning incidence of disease, genetic defects and diet. Stable isotopic compositions, especially those made on isolates of collagen from bones, have been used to help suggest principal dietary components. A significant problem in the use of collagen is its long–term stability, and the possibility of isotopic alteratio

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Cabanillas-Terán, Nancy, Héctor A. Hernández-Arana, Miguel-Ángel Ruiz-Zárate, Alejandro Vega-Zepeda, and Alberto Sanchez-Gonzalez. "Sargassum blooms in the Caribbean alter the trophic structure of the sea urchin Diadema antillarum." PeerJ 7 (August 30, 2019): e7589. http://dx.doi.org/10.7717/peerj.7589.

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The arrival of large masses of drifting Sargassum since 2011 has caused changes in the natural dynamics of Caribbean coastal ecosystems. In the summer of 2015, unprecedented and massive mats of S. fluitans and S. natans have been observed throughout the Mexican Caribbean including exceptional accumulations ashore. This study uses stable isotopes to assess the impact of Sargassum blooms on the trophic dynamics of the Diadema antillarum sea urchin, a keystone herbivore on many Caribbean reefs. Bayesian models were used to estimate the variations in the relative proportions of carbon and nitrogen

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McInerney, Francesca A., Caroline A. E. Strömberg, and James W. C. White. "The Neogene transition from C3 to C4 grasslands in North America: stable carbon isotope ratios of fossil phytoliths." Paleobiology 37, no. 1 (2011): 23–49. http://dx.doi.org/10.1666/09068.1.

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C4 grasses form the foundation of warm-climate grasslands and savannas and provide important food crops such as corn, but their Neogene rise to dominance is still not fully understood. Carbon isotope ratios of tooth enamel, soil carbonate, carbonate cements, and plant lipids indicate a late Miocene-Pliocene (8–2 Ma) transition from C3 vegetation to dominantly C4 grasses at many sites around the world. However, these isotopic proxies cannot identify whether the C4 grasses replaced woody vegetation (trees and shrubs) or C3 grasses. Here we propose a method for reconstructing the carbon isotope r

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Berdnikov, I. M., O. I. Goriunova, A. G. Novikov, et al. "Chronology of the Neolithic Ceramics of Baikal-Yenisei Siberia: Basic Ideas and New Data." Bulletin of the Irkutsk State University. Geoarchaeology, Ethnology, and Anthropology Series 33 (2020): 23–53. http://dx.doi.org/10.26516/2227-2380.2020.33.23.

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There are two main research areas in the Neolithic studies of the Baikal-Yenisei Siberia. One of them relates to research of mortuary traditions, another with a research of hunter-gatherer’s campsites. Ceramics is of the greatest importance for the cultural identification of campsites complexes. As a result of the Canadian-Russian project, for the Neolithic burials a clear chronological model based on AMS radiocarbon dates corrected for the freshwater reservoir effect (FRE) was created. There are several hypotheses for ceramic complexes that were proposed, but all of them predominantly were ba

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Verburg, Piet, Susan S. Kilham, Catherine M. Pringle, Karen R. Lips, and Dana L. Drake. "A stable isotope study of a neotropical stream food web prior to the extirpation of its large amphibian community." Journal of Tropical Ecology 23, no. 6 (2007): 643–51. http://dx.doi.org/10.1017/s0266467407004518.

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Rapid and massive amphibian population declines have been reported throughout upland areas of the Neotropics. The abundance and species richness of Neotropical amphibian communities suggest that losses of this magnitude are likely to have strong effects at the ecosystem level. To improve understanding of the implications of their loss we used stable isotope analysis to examine trophic relationships in an ecosystem in which amphibians are dominant in a second-order forest stream at 750 m asl in Parque Nacional Omar Torrijos Herrera, Panama. We analysed δ13C, δ15N and C:N ratios of major biotic

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Bestland, E., S. Milgate, D. Chittleborough, J. VanLeeuwen, M. Pichler, and L. Soloninka. "The significance and lag-time of deep through flow: an example from a small, ephemeral catchment with contrasting soil types in the Adelaide Hills, South Australia." Hydrology and Earth System Sciences 13, no. 7 (2009): 1201–14. http://dx.doi.org/10.5194/hess-13-1201-2009.

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Abstract. The importance of deep soil-regolith through flow in a small (3.4 km2) ephemeral catchment in the Adelaide Hills of South Australia was investigated by detailed hydrochemical analysis of soil water and stream flow during autumn and early winter rains. In this Mediterranean climate with strong summer moisture deficits, several significant rainfalls are required to generate soil through flow and stream flow [in ephemeral streams]. During autumn 2007, a large (127 mm) drought-breaking rain occurred in April followed by significant May rains; most of this April and May precipitation occu

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Bestland, E., S. Milgate, D. Chittleborough, J. VanLeeuwen, M. Pichler, and L. Soloninka. "The significance and lag-time of deep throughflow: an example from a small, ephemeral catchment with contrasting soil types in the Adelaide Hills, South Australia." Hydrology and Earth System Sciences Discussions 6, no. 2 (2009): 2599–632. http://dx.doi.org/10.5194/hessd-6-2599-2009.

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Abstract. The importance of deep throughflow in a small (3.4 km2) ephemeral catchment in the Adelaide Hills of South Australia was investigated by detailed hydrochemical analysis of soil water and stream flow during autumn and early winter rains. In this Mediterranean climate with strong summer moisture deficits, several significant rainfalls are required to generate soil throughflow and stream flow (in ephemeral streams). During Autumn 2007, a large (127 mm) drought-breaking rain occurred in April followed by significant May rains; most of this precipitation occurred prior to the initiation o

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Denimal, Sophie, Florent Barbecot, Laurent Dever, Nicolas Tribovillard, and Francis Meilliez. "Tracage chimique et isotopique des eaux souterraines en relation avec les eaux de lixiviation de terrils, bassin minier du Nord-Pas-de-Calais (France)." Bulletin de la Société Géologique de France 172, no. 1 (2001): 111–20. http://dx.doi.org/10.2113/172.1.111.

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Abstract Introduction. - In the Nord-Pas-de-Calais region (northern France), the mining activity linked to the coal extraction resulted in the existence of many mine spoils. Most of the time, the choice of the mine spoil location has been made without knowing the potential contamination of the aquifers contained in the underlying formations by substances which can be solubilized and released in relation with the weathering of these mine spoils. The aim of this study is to determine the possible role of the mine spoils in the sulfate mineralization of the chalk aquifer. Previous works [Bernard,

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Kejžar, Jan, Marta Jagodic Hudobivnik, Marijan Nečemer, Nives Ogrinc, Jasmina Masten Rutar, and Nataša Poklar Ulrih. "Characterization of Algae Dietary Supplements Using Antioxidative Potential, Elemental Composition, and Stable Isotopes Approach." Frontiers in Nutrition 7 (February 5, 2021). http://dx.doi.org/10.3389/fnut.2020.618503.

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Dietary supplements based on algae, known for their nutritional value and bioactive properties, are popular products among consumers today. While commercial algal products are regarded safe by numerous studies, information about the production and origin of such products is scarce. In addition, dietary supplements are not as strictly regulated as food and medicinal drugs. We characterized different algal products (kelps: Laminariales, Spirulina spp., Chlorella spp., and Aphanizomenon flos-aquae), obtained on Slovenian market, based on their elemental composition (X-ray fluorescence, inductivel

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