Dissertations / Theses on the topic 'Nitrogen stable isotopes'
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Nilsson, Lino. "Nitrogen transformations at the Kiruna mine : The use of stable nitrogen isotopes to trace nitrogen-transforming processes." Thesis, Uppsala universitet, Luft-, vatten och landskapslära, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-209419.
Full textCurtis-Summers, Shirley. "Stable Isotopes of Carbon and Nitrogen and Diet." Society of Antiquaries of Scotland, 2016. http://hdl.handle.net/10454/17856.
Full textSweeting, Christopher J. "Carbon and nitrogen stable isotopes as descriptors of fish trophodynamics." Thesis, University of Newcastle Upon Tyne, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.405361.
Full textLee, Vanessa Eileen. "Characterising dissolved nitrate in precipitation using stable nitrogen and oxygen isotopes /." Internet access available to MUN users only, 2005. http://collections.mun.ca/u?/theses,18576.
Full textWebb, Sarah Christine. "Stable carbon and nitrogen isotopes in insects : the influence of diet." Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389063.
Full textSouthworth, R. E. "The behaviour of the stable isotopes of nitrogen during diamond formation." Thesis, University College London (University of London), 2016. http://discovery.ucl.ac.uk/1478224/.
Full textTrandel, Marlee Anne. "Nitrogen and Carbon Stable Isotopes in Organically and Conventionally Grown Tomatoes." OpenSIUC, 2016. https://opensiuc.lib.siu.edu/theses/2013.
Full textVaiglova, Petra. "Neolithic agricultural management in the Eastern Mediterranean : new insight from a multi-isotope approach." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:c8824136-da35-43b2-a700-f458d0cc2fdf.
Full textWilson, J. M. "Natural abundance of '1'5N in soils : temporal and spatial variation in organic and inorganic N pools." Thesis, University of Newcastle Upon Tyne, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265428.
Full textNair, Richard Kiran Francis. "Using stable isotopes to investigate interactions between the forest carbon and nitrogen cycles." Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/10573.
Full textStrange, Malinda Range. "The effect of pathology on the stable isotopes of carbon & nitrogen." Diss., Online access via UMI:, 2006.
Find full textHARRISON, Sofie, and sofieh@student ecu edu au. "The influence of seabird-derived nutrients on island ecosystems in the oligotrophic marine waters of south-western Australia." Edith Cowan University. Computing, Health And Science: School Of Natural Sciences, 2006. http://adt.ecu.edu.au/adt-public/adt-ECU2007.0010.html.
Full textBostic, Joshua Neilson. "Stable Isotope Variability in the American Food Supply: Implications for Dietary Reconstruction Applications." Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/73870.
Full textMaster of Science
Cabana, Gilbert. "A comparative study of food-web processes in aquatic systems using stable isotopes." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0026/NQ29900.pdf.
Full textAssis, Cecília Kruszynski de. "Diet and ecosystem services of insectivorous bats assessed with stable isotopes." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/64/64135/tde-07032019-103440/.
Full textServiços ecossistêmicos são funções dos ambientes naturais e dos processos ecológicos dos quais humanos se beneficiam. Esses benefícios podem ser acessados por uma perspectiva econômica e ecológica. No presente estudo, nós destacamos um dos serviços ambientais fornecidos por morcegos: controle de pragas agrícolas. No Brasil, os estudos com morcegos insetívoros como potenciais supressores de pragas ainda são escassos, apesar de o país ser um dos maiores produtores agrícolas do mundo e abrigar uma alta diversidade desses animais. O uso de paisagens heterogêneas, formadas por vegetação nativa e lavouras agrícolas, otimiza o investimento aplicado nessa busca. Para tanto, descrevemos, pela primeira vez, a assembleia de morcegos em um ambiente heterogêneo de Piracicaba, o campus \"Luiz de Queiroz\", que possui desde áreas urbanizadas a agrícolas, disponibilizando diversos recursos alimentares para os morcegos. Ademais, testamos se há diferenças nos valores isotópicos (?13C e ?15N) entre as espécies de morcegos em relação à dieta, comportamento espacial de forrageamento, sexo ou classificação taxonômica para identificar quais grupos são os melhores supressores de pragas agrícolas. Utilizamos redes de neblina para a captura dos morcegos e análises de isótopos estáveis de carbono e nitrogênio (?13C e ?15N, respectivamente) para acessar sua fonte de dieta. Por meio das análises, determinamos a proporção de plantas com ciclos fotossintéticos do tipo C3 e C4 na dieta dos morcegos, bem como seu nível trófico. Capturamos 90 morcegos de 11 espécies, três famílias e quatro classes de dieta, correspondendo a 66% da riqueza estimada para o local. Destas, cinco são espécies classificadas insetívoras. Molossus molossus foi a espécie mais abundante, seguida por Artibeus lituratus e Glossophaga soricina. Valores de ?13C mostraram que insetívoros, frugívoros e nectarívoros consomem insetos, inclusive pragas, em diferentes proporções por espécie e grupo de dieta. O grupo mais efetivo no controle de pragas agrícolas foi M. molossus, seguido por A. planirostris. Os valores de ?15N mostraram que o nível trófico dos diferentes grupos alimentares de morcegos foi similar, de modo que eles são mais generalistas que previsto na literatura. Nosso estudo aponta a necessidade de quantificação desse importante serviço ecossistêmico promovido por morcegos, que podem reduzir doenças e prejuízos nas lavouras, além de combater vetores de doenças
Anderson, Kelly C. "Stable carbon and nitrogen isotope analyses of subfossil rats from Liang Bua (Flores, Indonesia)." Master's thesis, University of Central Florida, 2011. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4837.
Full textID: 030423461; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Thesis (M.A.)--University of Central Florida, 2011.; Includes bibliographical references.
M.A.
Masters
Anthropology
Sciences
Addison, Sarah Louise. "15N stable isotope probing of pulp and paper wastewaters." The University of Waikato, 2008. http://hdl.handle.net/10289/2399.
Full textSernagiotto, Erica Regina [UNESP]. "Rastreabilidade da farinha de vísceras de aves em codornas submetidas a longo período de criação utilizando a técnica dos isótopos estáveis 'delta' 'intpot. 13 c' e 'delta' 'intpot. 15 N'." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/95279.
Full textCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Universidade Estadual Paulista (UNESP)
O presente trabalho teve por objetivo avaliar a capacidade da técnica dos isótopos estáveis em rastrear a farinha de vísceras de aves (FVA), na alimentação de codornas de corte criadas por longo período, após a substituição da dieta com 8% de FVA por dieta vegetal. Foram utilizadas 320 codornas, distribuídas aleatoriamente em oito tratamentos: dieta vegetal (T1) e sete tratamentos com inclusão de 8% de FVA na dieta, um mantendo a dieta até o final do período experimental (T2), e nos demais a dieta foi substituída aos 42; 56; 70; 84; 98; 112 dias; respectivamente, por dieta vegetal. Para coleta das amostras de músculo peitoral foram sacrificadas ao acaso, quatro aves (n = 4) por tratamento, a cada 14 dias, sendo que no T1 e T2 tiveram início aos 42 dias e nos demais a partir da troca das dietas. Os resultados isotópicos obtidos foram submetidos à análise multivariada de variância (MANOVA) com auxílio do procedimento GLM do programa estatístico SAS. Os tratamentos diferiram do vegetal quando as aves foram sacrificadas duas semanas após a troca da dieta; após esse período os tratamentos experimentais tiveram comportamento semelhante ao vegetal, exceto o T3, que se mostrou semelhante ao T1 no abate 14 dias após a troca da dieta; e do T2 que em todos os períodos de comparação diferiu do T1. Conclui-se que a aplicação da técnica dos isótopos estáveis de carbono e nitrogênio na rastreabilidade da FVA, na alimentação de codornas de corte criadas por longo período é possível nas aves abatidas 14 dias após a troca de dieta, com exceção das aves sacrificadas aos 56 dias de idade.
The present work aimed to evaluate the capability of the stable isotope technique to trace poultry visceral meal (PVM) in the diet of meat quails raised for a long period after substitution of an 8% PVM diet for a vegetable diet. Three hundred and twenty poultries (320) were randomly distributed into eight treatments: vegetable diet (T1) and seven treatments containing 8% PVM in the diet: in one treatment, the same diet was kept until the end of the experimental period (T2), and in the remaining treatments, the diet was substituted at 42, 56, 70, 84, 98, and 112 days, respectively, for a vegetable diet. To collect chest muscle samples, four poultries (n = 4) per treatment were randomly sacrificed at every 14 days, starting at 42 days in T1 and T2 and from diet substitution in the remaining treatments. The obtained isotopic results were subjected to multivariate analysis of variance (MANOVA) using the GLM procedure of SAS statistical software. Treatments differed from the vegetable diet when poultries were sacrificed at two weeks following the diet substitution; after such period, the behavior of experimental treatments was similar to that of the vegetable diet, except for T3, which was similar to T1 at slaughtering at 14 days after the diet substitution, and T2 which, in all comparison periods, differed from T1. In conclusion, the technique of stable isotopes of carbon and nitrogen can be used to trace PVM in the diet of meat quails slaughtered at 14 days after diet substitution, except for poultries sacrificed at 56 days.
Dean, Susan. "Tracking sea lice : Lepeophtheirus salmonis, between host fish populations using stable carbon and nitrogen isotopes." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/31433.
Full textLand and Food Systems, Faculty of
Graduate
Afat, Abobaker Ali. "Reconstructing the Paleodiet of the Punic inhabitants at the site of Kerkouane (Tunisia)." Master's thesis, Universidade de Évora, 2021. http://hdl.handle.net/10174/31707.
Full textMcCall, Ashley E. "The Relationship of Stable Isotopes to Late Woodland and Fort Ancient Agriculture, Mobility, and Paleopathologies at the Turpin Site." University of Cincinnati / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1367924972.
Full textMinick, Kevan J. "Belowground Carbon and Nitrogen Cycling in a Loblolly Pine Forest Managed for Bioenergy Production." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/50587.
Full textPh. D.
Chen, Ruirui. "A study on apparent added nitrogen interactions and priming effects of soil organic matter using stable isotopes /." Kiel : Inst. für Pflanzenernährung und Bodenkunde, 2009. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=018975471&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
Full textMorin, Samuel. "Analyse de la composition isotopique de l'ion nitrate dans la basse atmosphère polaire et marine." Phd thesis, Université Paris-Est, 2008. http://tel.archives-ouvertes.fr/tel-00326229.
Full textJohnson, Laurie. "Assessing the effect of feather wear on carbon and nitrogen stable isotope ratios, and the use of stable isotopes to determine predator diets in the Namibian Islands marine protected area." Master's thesis, Faculty of Science, 2019. http://hdl.handle.net/11427/31248.
Full textMalkin, Elon M. "The Economically Important Nitrogen Pathways of Southwest Florida." Scholar Commons, 2010. http://scholarcommons.usf.edu/etd/3635.
Full textFahlman, John W. "Stable nitrogen isotopes as a method to source groundwater nitrate, field study of a municipal wastewater lagoon site." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0003/MQ45320.pdf.
Full textHarrison, Sofie A. "The influence of seabird-derived nutrients on island ecosystems in the oligotrophic marine waters of south-western Australia." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2006. https://ro.ecu.edu.au/theses/68.
Full textReitsema, Laurie Jean. "Stable Carbon and Nitrogen Isotope Analysis of Human Diet Change in Prehistoric and Historic Poland." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1330969837.
Full textPerkins, Matthew James. "Quantifying the effects of biodiversity on food web structure : a stable isotope approach." Thesis, University of Exeter, 2013. http://hdl.handle.net/10871/13941.
Full textLeda, Lucyna. "The Permian-Triassic boundary in the NW-Iranian Transcaucasus and in Central Iran." Doctoral thesis, Humboldt-Universität zu Berlin, 2020. http://dx.doi.org/10.18452/21106.
Full textPermian-Triassic boundary sections in the Julfa (NW Iran) and Abadeh (Central Iran) regions display a succession of three characteristic rock units, (1) the Paratirolites Limestone with the end-Permian mass extinction horizon at its top, (2) the Boundary Clay, and (3) the Early Triassic Elikah Formation with the conodont Permian-Triassic boundary at its base. The carbonate microfacies reveals a change, in the sections near Julfa, within the Paratirolites Limestone with an increasing number of intraclasts, Fe-Mn crusts, and biogenic encrustation. A decline in carbonate accumulation occurs towards the top of this unit, finally resulting in a complete demise of the carbonate factory. The skeletal carbonate factory was restored with the deposition of microbial carbonates at the base of the Elikah Formation at Julfa. At Baghuk Mountain (Abadeh region) large- and small-scale, arborescent microbialite buildups with conspicuous morphology and internal structure occur. In the Julfa and Abadeh regions, a prominent and globally traceable negative carbon isotope excursion indicates major perturbations of the carbon cycle around the P-Tr boundary. The sudden carbonate carbon isotope decrease below the extinction horizon is triggered by stratigraphic condensation that mirrors a deficit of the carbonate production/accumulation and/or a rapid geochemical change towards carbonate undersaturation. The negative carbon isotope trend before extinction horizon is gradual, suggesting that a longer lasting mechanism, such as thermal metamorphism of organic-rich sediments, and/or enhanced weathering on the continents may have caused the negative Permian-Triassic stable carbon isotope excursion. The bulk nitrogen isotope values in the sections of the Julfa region do not show any trend below the extinction horizon, pointing to rather mixing of different processes (nitrogen fixation and an equilibrium state between nitrate assimilation, nitrogen fixation, and denitrification).
Raymond, Jay E. "Use of Stable Isotopes to Trace the Fate of Applied Nitrogen in Forest Plantations to Evaluate Fertilizer Efficiency and Ecosystem Impacts." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/78738.
Full textPh. D.
Ghaui, Mark. "Identifying long term patterns and drivers of vegetation structure in an African savanna using stable carbon and nitrogen isotopes." Bachelor's thesis, University of Cape Town, 2010. http://hdl.handle.net/11427/26381.
Full textPointeau, Virginie M. "Water-use efficiency and productivity in native Canadian populations of Populus trichocarpa and Populus balsamifera." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/587.
Full textConsolmagno, Luiza Camargo. "Estimativa da taxa de turnover e fator de discriminação isotópico em espécies de quelônios." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/91/91131/tde-11102018-114205/.
Full textThe use of tracers such as stable carbon and nitrogen isotopes is crescent and complements the conventional techniques used in the studies referring to the diet in wild animals. This is possible because the isotopic value of the items used in the diet reflects their isotopic values on the tissues. The resulting isotopic difference called the discrimination factor or fractionation is associated with the metabolic processes required for nutrient incorporation to occur. The object of the study was to measure the incorporation time of isotopes into plasma and blood cells, components of re-portable non-lethal \"tissue\", and to determine the discriminant factor of five species of freshwater chelonians: Podocnemis expansa (Amazonia tortoise), Podocnemis unifilis (tracajá), Phrynops geofroanus (geoffroy´s side necked turtle), Trachemys scripta (red-eared slider turtle) and Trachemys dorbigni (d\'orbigny\'s slider). The isotopic differences of 10 adult individuals of each species kept in captivity were measured through shifting diets with different isotopic values. With the diet variation, carbon and nitrogen turnover was estimated between 7 and 185 days by non-linear exponential regression, when the new fractionation factors were estimated. The turnover time for the chelonians species varied from 72 to 337 days for carbon, and from 29 to 270 days for the plasma nitrogen. In blood cells, the turnover ranged from 3 to 373 days for carbon, and from 51 to 216 days for nitrogen. Discrimination factors that were, in average, close to zero for carbon and between 3 and 4‰ for nitrogen ranged from 1.01 to 3.28‰ for 13C and -0.76 to 0.49‰ for 15N in plasma, and from 1.49 to 3.98‰ for 13C and 0.99 to 4.69 for 15N in blood cells, with a decrease of 3.7‰ and an increase of 6.2‰, respectively for carbon and nitrogen in the new diet. The difference found between the discrimination factors calculated before and after the diet shift, showed that stable isotopes incorporation probably occurs in a heterogenous way in tissues. According to the literature it was possible to analyze that factors such as isotopic memory, metabolic routes and reptiles characteristic elements are possibly linked to slower turnover, different from endothermic animals in which this process is faster.
Sernagiotto, Erica Regina 1983. "Rastreabilidade da farinha de vísceras de aves em codornas submetidas a longo período de criação utilizando a técnica dos isótopos estáveis 'delta' 'intpot. 13 c' e 'delta' 'intpot. 15 N' /." Botucatu : [s.n.], 2009. http://hdl.handle.net/11449/95279.
Full textBanca: Carlosw Ducatti
Banca: Valquíria Cação da Cruz
Resumo: O presente trabalho teve por objetivo avaliar a capacidade da técnica dos isótopos estáveis em rastrear a farinha de vísceras de aves (FVA), na alimentação de codornas de corte criadas por longo período, após a substituição da dieta com 8% de FVA por dieta vegetal. Foram utilizadas 320 codornas, distribuídas aleatoriamente em oito tratamentos: dieta vegetal (T1) e sete tratamentos com inclusão de 8% de FVA na dieta, um mantendo a dieta até o final do período experimental (T2), e nos demais a dieta foi substituída aos 42; 56; 70; 84; 98; 112 dias; respectivamente, por dieta vegetal. Para coleta das amostras de músculo peitoral foram sacrificadas ao acaso, quatro aves (n = 4) por tratamento, a cada 14 dias, sendo que no T1 e T2 tiveram início aos 42 dias e nos demais a partir da troca das dietas. Os resultados isotópicos obtidos foram submetidos à análise multivariada de variância (MANOVA) com auxílio do procedimento GLM do programa estatístico SAS. Os tratamentos diferiram do vegetal quando as aves foram sacrificadas duas semanas após a troca da dieta; após esse período os tratamentos experimentais tiveram comportamento semelhante ao vegetal, exceto o T3, que se mostrou semelhante ao T1 no abate 14 dias após a troca da dieta; e do T2 que em todos os períodos de comparação diferiu do T1. Conclui-se que a aplicação da técnica dos isótopos estáveis de carbono e nitrogênio na rastreabilidade da FVA, na alimentação de codornas de corte criadas por longo período é possível nas aves abatidas 14 dias após a troca de dieta, com exceção das aves sacrificadas aos 56 dias de idade.
Abstract: The present work aimed to evaluate the capability of the stable isotope technique to trace poultry visceral meal (PVM) in the diet of meat quails raised for a long period after substitution of an 8% PVM diet for a vegetable diet. Three hundred and twenty poultries (320) were randomly distributed into eight treatments: vegetable diet (T1) and seven treatments containing 8% PVM in the diet: in one treatment, the same diet was kept until the end of the experimental period (T2), and in the remaining treatments, the diet was substituted at 42, 56, 70, 84, 98, and 112 days, respectively, for a vegetable diet. To collect chest muscle samples, four poultries (n = 4) per treatment were randomly sacrificed at every 14 days, starting at 42 days in T1 and T2 and from diet substitution in the remaining treatments. The obtained isotopic results were subjected to multivariate analysis of variance (MANOVA) using the GLM procedure of SAS statistical software. Treatments differed from the vegetable diet when poultries were sacrificed at two weeks following the diet substitution; after such period, the behavior of experimental treatments was similar to that of the vegetable diet, except for T3, which was similar to T1 at slaughtering at 14 days after the diet substitution, and T2 which, in all comparison periods, differed from T1. In conclusion, the technique of stable isotopes of carbon and nitrogen can be used to trace PVM in the diet of meat quails slaughtered at 14 days after diet substitution, except for poultries sacrificed at 56 days.
Mestre
Pastershank, Georgine M. "Unifying ecosystem concepts and mercury biomagnification in an estuarine environment using stable isotopes (delta-carbon-13 and delta nitrogen-15)." Thesis, University of Ottawa (Canada), 2001. http://hdl.handle.net/10393/9387.
Full textAl-Reasi, Hassan Ali. "Tracking mercury biomagnification in fish from the Gulf of Oman using stable isotopes (carbon-13carbon-12 and nitrogen-15nitrogen-14)." Thesis, University of Ottawa (Canada), 2005. http://hdl.handle.net/10393/26836.
Full textWeber, Sarah C. "From rivers to natural gas: The influence of allochthonous inputs on marine nitrogen fixation and the carbon cycle." Thesis, Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54470.
Full textBlaszczyck, D., Julia Beaumont, A. Krzyszowski, D. Poliński, and A. Drozd-Lipińska. "Social status and diet. Reconstruction of diet of individuals buried in some early medieval chamber graves from Poland by carbon and nitrogen stable isotopes analysis." Science Direct, 2021. http://hdl.handle.net/10454/18572.
Full textThe study presents results of the investigations of diet based on carbon and nitrogen stable isotope ratios (δ13C and δ15N) of the bone collagen of individuals buried in medieval elite chamber graves from the territory of the state of the first Piasts, Poland (the second half of the 10th and the first half of the 11th century). The aim of the research was to determine the diet of individuals buried in such funerary structures, to compare this with commoners buried in ordinary graves, and investigate any sex-related patterns. Rib bone samples were taken from individuals buried in chamber graves at Bodzia, Dziekanowice, Pień and Sowinki. Results indicate that the elite male diet was based on C3 plants with possible contribution of some C4 plants (millet) and substantial consumption of animal proteins including fish. The bone collagen δ13C and δ15N of male chamber burials suggested consumption of higher trophic level foodstuffs (meat and fish) whilst the female diet, and that of the juveniles, was similar to the commoners in the rest of the population.
Husic, Admin. "NUMERICAL MODELING AND ISOTOPE TRACERS TO INVESTIGATE KARST BIOGEOCHEMISTRY AND TRANSPORT PROCESSES." UKnowledge, 2018. https://uknowledge.uky.edu/ce_etds/70.
Full textMontey, Nicole R. "Investigation of pygmy sperm whale (Kogia breviceps ) populations in the southeastern United States using stable isotopes of carbon, nitrogen, and oxygen in teeth." Thesis, College of Charleston, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1587301.
Full textThe pygmy sperm whale (Kogia breviceps) is currently the second-most commonly stranded cetacean in the Southeastern United States (SEUS), but information concerning their population structure is severely limited. This study utilized stable isotope analysis to investigate the possible migratory patterns and population structure of K. breviceps among six different regions in the SEUS. Combined growth layers from different regions of the teeth were subsampled via dental drill and analyzed representing four different age classes: calf, juvenile, sub-adult, and adult, as well as four yearlings that had stranded with their mothers. Stable isotope ratios of carbon and nitrogen were measured in the organic component of 46 teeth, and oxygen isotope ratios were measured in the inorganic (hydroxyapatite) component of 21 teeth obtained from stranded individuals. There was a high degree of individual variability in δ13C, δ 15N, and δ18O resulting in no significant differences between the six different regions: South Carolina, Georgia, Northern, Central, and Southern Florida, and the Gulf of Mexico. Differences between the age classes were significant for δ13C and δ 15N. Adults exhibited significantly more negative δ13 C than subadults. These results support a previously hypothesized inshore-offshore migration for Kogia breviceps. Yearlings displayed significantly higher δ15N values than all other age classes due to nursing. A slight increase in δ15N from juvenile to adult supports a possible ontogenetic shift in the trophic level of prey. Results from this study provide the first carbon and nitrogen isotope values from different age classes of pygmy sperm whales as well as the first reported oxygen isotopes values for this species.
Hooker, Toby D. "Consequences of Vegetation Change on the Dynamics of Labile Organic Matter and Soil Nitrogen Cycling in a Semiarid Ecosystem." DigitalCommons@USU, 2009. https://digitalcommons.usu.edu/etd/411.
Full textBoehme-Terrana, Linae Marie. "Trace metals and stable isotopes as tracers of life history and trophic connections in estuarine-dependent fish from Tampa Bay, Florida." [Tampa, Fla.] : University of South Florida, 2007. http://purl.fcla.edu/usf/dc/et/SFE0002241.
Full textMamontov, Alexander. "Hydroxylation et halogénation directe et sélective des composés azotés en milieu superacide." Thesis, Poitiers, 2018. http://www.theses.fr/2018POIT2267.
Full textLate-stage functionalization can now be considered as a synthetic tool of choice to create molecular diversity, especially in a medicinal chemistry context. For example, aromatic C-H bonds can be regarded as functional groups and points of potential diversification to generate new analogs of a lead structure without resorting to de novo synthesis.The direct functionalization of elaborated compounds can also be done using superacid chemistry as demonstrated by the previous work of professor Jacquesy. One of the best examples of this strategy is certainly the direct transformation of vinorelbine (Navelbine®) by fluorination in superacid conditions to lead to its difluorinated analogue (Vinflunine), marketed by Pierre Fabre laboratories as an anticancer agent Javlor®.In this context, these studies focused on the development of new methods for the direct functionalization of aromatic nitrogen containing compounds.In particular, this work aimed at developing new synthetic tools in superacid for:1. the direct hydroxylation of aromatic compounds;2. the halogenation of aromatic nitrogen compounds from simple anilines to naturally occurring or synthetic compounds;3. the synthesis of labelled compounds with stable isotopes
Cleary, Daniel Martin. "A Bat-Guano-Derived δ15N and δ13C Record of Paleoenvironmental Change: Zidită Cave, Romania." Scholar Commons, 2015. http://scholarcommons.usf.edu/etd/5928.
Full textSigman, Daniel M. "The Role of Biological Production in Pleistocene Atmospheric Carbon Dioxide Variations and the Nitrogen Isotope Dynamics of the Southern Ocean." Ft. Belvoir : Defense Technical Information Center, 1997. http://handle.dtic.mil/100.2/ADA342811.
Full text"September 1997." "Funding was provided by National Science Foundation Grant OCE-9201286, National Science Foundation Graduate Fellowship Program, and the JOI/USSAC Ocean Drilling Graduate Fellowship Program." Includes bibliographical references (p. 152-153).
Wexler, S. K. "An investigation into the sources, cycling and attenuation of nitrate in an agricultural lowland catchment using stable isotopes of nitrogen and oxygen in nitrate." Thesis, University of East Anglia, 2010. https://ueaeprints.uea.ac.uk/24211/.
Full textNardoto, Gabriela Bielefeld. "Abundância natural de 15N na Amazônia e Cerrado - implicações para a ciclagem de nitrogênio." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/91/91131/tde-30012006-155758/.
Full textThe Amazon terra-firme forest and Cerrado occur in the Brazilian tropical region characterized by low soil fertility and a quite diverse climatological condition, mainly related to extend and intensity of the dry and wet seasons. Despite the differences in evolutionary character, water economy and strategies in nutrient cycling, these systems are known for a high number of woody legumes. Othe objective of this study was to investigate the nitrogen dynamics, with emphasis on the biological nitrogen fixation, on some types of natural vegetation from Brazil. Areas of terra-firme forest on plateau, terra-firme forest on baixio and campinarana, situated in the Brazilian Amazon region and areas of cerrado sensu stricto submitted to different fire regimes, situated in Central region of Brazil, were investigated. Total N concentration varied from 1.2 to 4.1 g kg-1 at the surface (0-5 cm) to ~ 0.5 g kg-1 at 50 cm depth. Regardless of the site, a large increase in δ15N was observed in the first 50 cm of the soil, although the soil profiles from terra-firme forest in Manaus and Santarém were more enriched in 15N than the other profiles. All terra-firme forests showed higher N, P and Ca concentrations, and δ15N, in the litter, as well as lower C:N ratio compared to the other studied sites. Within-site, foliar δ15N (~ 10 ) did not differ between legumes and non-legumes, but legumes had higher foliar N concentrations. Forests on fertile soils were enriched in 15N relative to those on poorer soils. Foliar δ15N was positively correlated with the length of the dry season in terra-firme forests along the Amazon while foliar N did not decrease as precipitation increases. Terra-firme forests are N-rich ecosystems (open N-cycle) compared to the Cerrado where the large range of δ15N reflects mechanisms to sustain such diversity in this nutrient-poor and water-stressed environment. Precipitation seasonality (dry versus wet season), fire frequency and ability to fix atmospheric N (legumes vs non-legumes), did not reflect significant differences in the δ15N values of Cerrado leaves. Both terra-firme forest and cerrado s.s. are limited more by P than by N, although N limitation is higher in the latter. Three aspects ought to be concerned describing the patterns found in this work. First, differences in plant versus soil δ15N; second, differences in the characteristic of the N cycle (the magnitude of inputs and outputs versus the quantity of N within systems); and third, variations on isotopic fractionation during N loss. Therefore, differences in the relative openness of the N cycle seems to contribute most strongly to fertility-related variation in N-15, while differences in fractionation during output contribute more strongly to rainfallassociated variation.
Edwards, Keith. "A proposed methodology for predicting the carbon and nitrogen stable isotope measures of K'inich Yax K'uk Mo', Copan dynastic founder." Master's thesis, University of Central Florida, 2011. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4887.
Full textID: 030423403; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Thesis (M.A.)--University of Central Florida, 2011.; Includes bibliographical references (p. 72-79).
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