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| Registros recuperados: 118 | |
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| Portail, Marie; Brandily, Christophe; Cathalot, Cecile; Colaco, Ana; Gelinas, Yves; Husson, Berengere; Sarradin, Pierre-marie; Sarrazin, Jozee. |
| The assessment and comparison of food webs across various hydrothermal vent sites can enhance our understanding of ecological processes involved in the structure and function of biodiversity. The Menez Gwen, Lucky Strike and Rainbow vent fields are located on the Azores triple junction of the Mid-Atlantic Ridge. These fields have distinct depths (from 850 to 2320 m) and geological contexts (basaltic and ultramafic), but share similar faunal assemblages defined by the presence of foundation species that include Bathymodiolus azoricus, alvinocarid shrimp and gastropods. We compared the food webs of 13 faunal assemblages at these three sites using carbon and nitrogen stable isotope analyses (SIA). Results showed that photosynthesis-derived organic matter is a... |
| Tipo: Text |
Palavras-chave: Mid-Atlantic Ridge; Hydrothermal vents; Food webs; Stable isotopes; Functional traits. |
| Ano: 2018 |
URL: http://archimer.ifremer.fr/doc/00414/52551/53732.pdf |
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| Chalk,Phillip Michael. |
| Abstract Brazilian scientists have played a pioneering role in developing and applying stable isotope methodologies, in terms of natural abundance and enriched levels, to trace carbon and nutrient flows in terrestrial ecosystems, including natural and agroecosystems. Significant contributions have been made in the areas of biological N2 fixation, carbon dynamics in soil, synthesis and evaluation of labeled fertilizers, and food science. These contributions have originated from several decentralized units of Embrapa, from research institutions, and from federal or state universities. In order to capitalize the existing Brazilian expertise, it is necessary to provide, at an institutional level, analytical facilities for stable isotope research, aiming to... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Biological N2 fixation; Fertilizer use efficiency; Food science; Labeled fertilizer; Soil carbon; Stable isotopes. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2016000901039 |
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| Chaalali, Aurelie; Brind'Amour, Anik; Dubois, Stanislas; Le Bris, Herve. |
| Through their tissues or activities, engineer species create, modify, or maintain habitats and alter the distribution and abundance of many plants and animals. This study investigates key ecological functions performed by an engineer species that colonizes coastal ecosystems. The gregarious tubiculous amphipod Haploops nirae is used as a biological model. According to previous studies, the habitat engineered by H.nirae (i.e., Haploops habitat) could provide food and natural shelter for several benthic species such as benthic diatoms belonging to the gender Navicula, the micrograzer Geitodoris planata, or the bivalve Polititapes virgineus. Using data from scientific surveys conducted in two bays, this study explored whether (1) the Haploops sandy-mud... |
| Tipo: Text |
Palavras-chave: Coastal nurseries; Fish community; Haploops nirae; Isotopic diversity indices; Stable isotopes. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00396/50722/51431.pdf |
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| Voelker, A. H. L.; De Abreu, L.; Schoenfeld, J.; Erlenkeuser, H.; Abrantes, F.. |
| The surface water hydrography along the western Iberian margin, as part of the North Atlantic's eastern boundary upwelling system, consists of a complex, seasonally variable system of equatorward and poleward surface and subsurface currents and seasonal upwelling. Not much information exists to ascertain if the modern current and productivity patterns subsisted under glacial climate conditions, such as during marine isotope stage (MIS) 2, and how North Atlantic meltwater events, especially Heinrich events, affected them. To help answer these questions we are combining stable isotope records of surface to subsurface dwelling planktonic foraminifer species with sea surface temperature and export productivity data for four cores distributed along the western... |
| Tipo: Text |
Palavras-chave: Iberian margin; Last Glacial Maximum; Heinrich events; Planktonic foraminifer; Stable isotopes; Productivity. |
| Ano: 2009 |
URL: https://archimer.ifremer.fr/doc/00218/32906/31419.pdf |
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| Respschläger, Janne. |
| The Atlantic meridional overturning circulation (AMOC) transports warm saline water from low to high northern latitudes where it cools, sinks down and returns southward as deepwater flow. By the heat transfer from low to high latitudes, AMOC contributes in balancing the global energy budget and thus is an important part of global climate system. Within this study the impact of AMOC changes on surface and deepwater hydrography of the subtropical North Atlantic is investigated by the use of high-resolution sediment cores from a coring site located south of the Azores at the eastern flank of the Mid Atlantic Ridge. The Azores coring site is situated in the subtropical eastern North Atlantic (NA) at the boundary between warm Subtropical Gyre Water (STG) and... |
| Tipo: Text |
Palavras-chave: Paleoceanography; AMOC; Subtropical gyre; Deglacial; Multiproxy SST; BWT; Stable isotopes; Planktonic and benthic foraminifera. |
| Ano: 2013 |
URL: https://archimer.ifremer.fr/doc/00493/60444/63889.pdf |
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| Ritt, Benedicte; Duperron, Sebastien; Lorion, Julien; Lazar, Cassandre; Sarrazin, Jozee. |
| Recently, small Idas-like mussels have been discovered living on carbonate crusts associated with cold-seeps in the Marmara Sea. These mussels, here referred to as Idas-like nov. sp., differ morphologically and genetically from another species identified as Idas aff. modiolaeformis, living in the same type of ecosystem in the Nile Deep-Sea Fan (eastern Mediterranean Sea). A phylogenetic analysis confirms the distinction between the two species, which belong to highly divergent lineages. Carbon stable isotope values, as well as the detection of thiotroph-related bacteria in the gill tissue, support the presence of a symbiotic, thiotroph-derived nutrition. In contrast, Idas aff. modiolaeformis displays six different types of symbionts. Finally our... |
| Tipo: Text |
Palavras-chave: Mytilidae; Idas-like; Cold-seeps; Marmara Sea; Phylogeny; Symbiosis; Stable isotopes. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00098/20915/19672.pdf |
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| Issac, Pierre; Robert, Marianne; Le Bris, Hervé; Rault, Jonathan; Pawlowski, Lionel; Kopp, Dorothee. |
| We used stable isotope ratio and gut content analyses to determine and compare the feeding ecology of two commercially important predator species, Lophius piscatorius and Lophius budegassa in the Celtic sea, where data concerning their trophic ecology remain sparse. This study included two areas and two size-classes, showing that anglerfish in the Celtic sea are mainly piscivorous top predators as observed in other marine waters. However, a substantial part of the diet of the fish in the small size classes consists of benthic macro-invertebrates, mainly Crustaceans. Despite the common knowledge that they are opportunistic predators that display a low degree of prey selectivity, our results suggest that the two species have different trophic niches when... |
| Tipo: Text |
Palavras-chave: Lophius; Gut content; Stable isotopes; Trophic niche; Trophic segregation; Top predator. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00395/50614/51326.pdf |
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| Toner, Brandy M.; Rouxel, Olivier; Santelli, Cara M.; Bach, Wolfgang; Edwards, Katrina J.. |
| Hydrothermal sulfide chimneys located along the global system of oceanic spreading centers are habitats for microbial life during active venting. Hydrothermally extinct, or inactive, sulfide deposits also host microbial communities at globally distributed sites. The main goal of this study is to describe Fe transformation pathways, through precipitation and oxidation-reduction (redox) reactions, and examine transformation products for signatures of biological activity using Fe mineralogy and stable isotope approaches. The study includes active and inactive sulfides from the East Pacific Rise 9 degrees 50'N vent field. First, the mineralogy of Fe(III)-bearing precipitates is investigated using microprobe X-ray absorption spectroscopy (RXAS) and X-ray... |
| Tipo: Text |
Palavras-chave: Hydrothermal; East Pacific Rise; X-ray absorption spectroscopy; Stable isotopes; Micro-environment; Mineral alteration; Iron; Biosignature. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00337/44810/44375.pdf |
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| Djeghri, Nicolas; Pondaven, Philippe; Stockenreiter, Maria; Behl, Stephan; Huang, Jessica Y. T.; Hansen, Thomas; Patris, Sharon; Ucharm, Gerda; Stibor, Herwig. |
| Mixotrophic organisms are increasingly recognized as important components of ecosystems, but the factors controlling their nutrition pathways (in particular their autotrophy–heterotrophy balance) are little known. Both autotrophy and heterotrophy are expected to respond to density‐dependent mechanisms but not necessarily in the same direction and/or strength. We hypothesize that the autotrophy–heterotrophy balance of mixotrophic organisms might therefore be a function of population densities. To investigate this relationship, we sampled mixotrophic jellyfish holobionts (host, Mastigias papua etpisoni; symbiont, Cladocopium sp.) in a marine lake (Palau, Micronesia) on six occasions (from 2010 to 2018). Over this period, population densities varied ~100... |
| Tipo: Text |
Palavras-chave: Density dependence; Jellyfish; Marine lakes; Mixotrophy; Stable isotopes; Symbiosis; Zooxanthellae. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00663/77469/79159.pdf |
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| Oliveira,R.P.; Ducatti,C.; Carrijo,A.S.; Pezzato,A.C.; Denadai,J.C.; Sartori,J.R.; Cruz,V.C.. |
| The inclusion of poultry viscera meal (VM) in broiler diets to possibly replace it with strictly vegetable diet (VE) and vice-versa, using the technique of carbon and nitrogen stable isotopes in different tissues was traced. One hundred ninety-two one-day-old chicks that had been distributed randomly were used in twelve experimental treatments with four replications of four chicks each. The treatments consisted of vegetable diet (VG) for diets containing FV going after a certain age or the reverse, in which the birds began feeding VM on diet and then switched to VE diet. At 42 days of age, samples of pectoral muscle (Pectoralis major), keel and tibia were collected, with later determination of isotopic ratios (13C/12C and 15N/14N). The stable isotopes... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Broiler; Poultry viscera meal; Stable isotopes; Carbon-13; Nitrogen-15. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352012000500033 |
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| Augusto,Fernanda Gaudio; Tassoni Filho,Mauricio; Ferreira,Anderson; Pereira,Alexandre Leandro; Camargo,Plínio Barbosa de; Martinelli,Luiz Antonio. |
| Terrestrial invertebrates link terrestrial systems to aquatic ones, making vegetal material produced in the watershed available to aquatic food webs. In this study, using carbon and nitrogen stable isotopes, we evaluated the importance of introduced C4 grasses as a source of carbon in aquatic food webs of headwater streams of the coastal Atlantic Forest located on the north coast of the State of São Paulo, in the southeastern region of Brazil. Terrestrial invertebrates were collected in two streams: one where the main land cover was pristine montane Atlantic Forest (forest stream) and another where the main land cover was introduced C4 forage grasses for livestock (pasture stream). The average δ13C of terrestrial invertebrates collected in the forest... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Atlantic Forest; Land use; Streams; Stable isotopes; Terrestrial invertebrate. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032015000200104 |
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| Fontanier, Christophe; Dissard, D.; Ruffine, Livio; Mamo, B.; Ponzevera, Emmanuel; Pelleter, Ewan; Baudin, F.; Roubi, Angelique; Cheron, Sandrine; Boissier, Audrey; Gayet, Nicolas; Bermell-fleury, S.; Pitel, M.; Guyader, Vivien; Lesongeur, Francoise; Savignac, F.. |
| In this preliminary study, we investigate living (stained) foraminifera from the Sea of Marmara. We focus on the faunal composition and geochemical signatures (trace elements, carbon and oxygen stable isotopes) in foraminiferal tests at two deep-sea sites (329 and ~1240 m depth respectively). Documented by ROV observations and sampling, both study areas are heterogeneous (including bacterial mats and carbonate concretions), proximal to cold seeps and consist of dysoxic bottom water (O2<20 µmol/L). The prevailing dysoxia at both study areas restricts foraminiferal diversity to very low values (S<9, H’<0.97). Stress-tolerant species Bolivina vadescens and Globobulimina affinis dominate living faunas at both sites. The highest foraminiferal standing... |
| Tipo: Text |
Palavras-chave: Living (stained) benthic foraminifera; Sea of Marmara; Extreme ecosystems; Trace elements; Stable isotopes. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00416/52774/53646.pdf |
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| Risebrobakken, Bjorg; Andersson, Carin; De Schepper, Stijn; Mcclymont, Erin L.. |
| The Pliocene (5.3-2.6Ma) is often described as a relatively stable climatic period, with warm temperatures characterizing high latitudes. New suborbital resolved stable isotope records from Ocean Drilling Program Hole 642B in the eastern Nordic Seas document that the Pliocene was not a stable period characterized by one climate. Rather, seven distinct climate phases, each lasting between 150,000 and 400,000years, are identified and characterized in the time interval 5.1-3.1Ma. Four of the transitions between the defined climate phases occurred close to an eccentricity minimum and a minimum in amplitude of change for Northern Hemisphere summer insolation, while two occurred around an eccentricity maximum and a maximum in amplitude in insolation change.... |
| Tipo: Text |
Palavras-chave: Pliocene; Nordic Seas; Stable isotopes; Diagenetic calcite; Paleogeography; External and internal forcing. |
| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00504/61599/65864.pdf |
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| Trystram, Clément; Roos, David; Guyomard, David; Jaquemet, Sébastien. |
| Understanding drivers of trophic partitioning at the community level is an essential prerequisite to the establishment of ecosystem-based management of fisheries. In this study, we identify drivers of trophic partitioning within a community of epipelagic fish and a community of deep-water fishes off Reunion Island. Effects of intrinsic (species identity, etc.) and environmental variables (fishing zone, month) on stomach content composition and stable isotope ratios were tested using regression trees and linear models respectively. Our results demonstrated firstly an independence of both communities, with very few common prey although they occurred in similar localities, and secondly, very different patterns of resources partitioning among each community.... |
| Tipo: Text |
Palavras-chave: Trophic partitioning; Deep-sea; Epipelagic; Predator; Stable isotopes; Stomach contents. |
| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00353/46440/46184.pdf |
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| Registros recuperados: 118 | |
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