Influence of ontogeny on stable isotope ratios and trophic discrimination factors of African penguin (Spheniscus demersus) tissues

Abstract Carbon and nitrogen stable isotope ratios are used widely to describe wildlife animal diet composition and trophic interactions. To reconstruct consumer diet, the isotopic differences between consumers and their diet items—called the trophic discrimination factor (TDF)—must be known. Proxies of diet composition are sensitive to the accuracy of TDFs. However, specific TDFs are still missing for many species and tissues because only a few controlled studies have been carried out on captive animals. The aim of this study was to estimate TDFs for hair and blood for carbon and nitrogen stable isotopes for caribou, moose, white-tailed deer, eastern coyote, and black bear. We obtained stable isotope ratios for diet items, hair, and blood samples, of 21 captive adult mammals. Diet–tissue discrimination factors for carbon in hair (∆ 13CLE) ranged from 0.96‰ to 3.72‰ for cervids, 3.01‰ to 3.76‰ for coyote, and 5.15‰ to 6.35‰ for black bear, while nitrogen discrimination factors (∆ 15N) ranged from 2.58‰ to 5.95‰ for cervids, 2.90‰ to 3.13‰ for coyote, and 4.48‰ to 5.44‰ for black bear. The ∆ 13CLE values in coyote blood components ranged from 2.20‰ to 2.69‰ while ∆ 15N ranged from 3.30‰ to 4.41‰. In caribou serum, ∆ 13CLE reached 3.34 ± 1.28‰ while ∆ 15N reached 5.02 ± 0.07‰. The TDFs calculated in this study will allow the evaluation of diet composition and trophic relationships between these five mammal species and will have important implications for the study of endangered caribou populations for which the use of noninvasive tissue sampling is highly relevant.

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How protein quality drives incorporation rates and trophic discrimination of carbon and nitrogen stable isotope ratios in a freshwater first‐feeding fish

Freshwater Biology ◽

10.1111/fwb.13578 ◽

2020 ◽

Vol 65 (11) ◽

pp. 1870-1882

Author(s):

Sarah Nahon ◽

Sarah Séité ◽

Sébastien Lefebvre ◽

Joanna Kolasinski ◽

Pierre Aguirre ◽

...

Keyword(s):

Stable Isotope ◽

Protein Quality ◽

Isotope Ratios ◽

Stable Isotope Ratios ◽

Nitrogen Stable Isotope ◽

Carbon And Nitrogen ◽

First Feeding ◽

Trophic Discrimination

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TRANSFER EFFICIENCY FROM PRIMARY PRODUCERS TO RUDITAPES PHILIPPINARUM ON AN INTERTIDAL FLAT IN HIROSHIMA BAY, JAPAN

Proceedings of International Conference "Managinag risks to coastal regions and communities in a changinag world" (EMECS'11 - SeaCoasts XXVI) ◽

10.31519/conferencearticle_5b1b93b4af8c32.73166623 ◽

2017 ◽

Author(s):

Sosuke Otani ◽

Akira Umehara ◽

Haruka Miyagawa ◽

...

Keyword(s):

Stable Isotope ◽

Secondary Production ◽

Isotope Ratios ◽

Ruditapes Philippinarum ◽

Transfer Efficiency ◽

Food Sources ◽

Stable Isotope Ratios ◽

Primary Producers ◽

Nitrogen Stable Isotope ◽

Carbon And Nitrogen

Fish yields of Ruditapes philippinarum have been decreased and the resources have not yet recovered. It needs to clarify food sources of R. philippinarum, and relationship between primary and secondary production of it. The purpose on this study is to reveal transfer efficiency from primary producers to R. philippinarum and food sources of R. philippinarum. The field investigation was carried out to quantify biomass of R. philippinarum and primary producers on intertidal sand flat at Zigozen beach in Hiroshima Bay, Japan. In particular, photosynthetic rates of primary producers such as Zostera marina, Ulva sp. and microphytobenthos were determined in laboratory experiments. The carbon and nitrogen stable isotope ratios for R. philippinarum and 8 potential food sources (microphytobenthos, MPOM etc) growing in the tidal flat were also measured. In summer 2015, the primary productions of Z. marina, Ulva sp. and microphytobenthos were estimated to be 70.4 kgC/day, 43.4 kgC/day and 2.2 kgC/day, respectively. Secondary production of R. philippinarum was 0.4 kgC/day. Contribution of microphytobenthos to R. philippinarum as food source was 56-76% on the basis of those carbon and nitrogen stable isotope ratios. Transfer efficiency from microphytobenthos to R. philippinarum was estimated to be 10-14%. It was suggested that microphytobenthos might sustain the high secondary production of R. philippinarum, though the primary production of microphytobenthos was about 1/10 compared to other algae.

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Stable Isotope Ratios of Herbs and Spices Commonly Used as Herbal Infusions in the Italian Market

ACS Omega ◽

10.1021/acsomega.1c00274 ◽

2021 ◽

Author(s):

Purna K. Khatri ◽

Roberto Larcher ◽

Federica Camin ◽

Luca Ziller ◽

Agostino Tonon ◽

...

Keyword(s):

Stable Isotope ◽

Isotope Ratios ◽

Stable Isotope Ratios ◽

Italian Market ◽

Herbal Infusions ◽

Herbs And Spices

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Are stable isotope ratios suitable for describing niche partitioning and individual specialization?

Ecological Applications ◽

10.1002/eap.2392 ◽

2021 ◽

Author(s):

Philip Matich ◽

Joseph J. Bizzarro ◽

Oliver N. Shipley

Keyword(s):

Stable Isotope ◽

Niche Partitioning ◽

Isotope Ratios ◽

Stable Isotope Ratios ◽

Individual Specialization

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Elemental and Isotopic Characterization of Tobacco from Umbria

Metabolites ◽

10.3390/metabo11030186 ◽

2021 ◽

Vol 11 (3) ◽

pp. 186

Author(s):

Luana Bontempo ◽

Daniela Bertoldi ◽

Pietro Franceschi ◽

Fabio Rossi ◽

Roberto Larcher

Keyword(s):

Stable Isotope ◽

Economic Value ◽

Isotope Ratios ◽

Stable Isotope Ratios ◽

Umbria Region ◽

Geographical Regions ◽

Isotopic Characterization ◽

First Time ◽

Micro Elements

Umbrian tobacco of the Virginia Bright variety is one of the most appreciated tobaccos in Europe, and one characterized by an excellent yield. In recent years, the Umbria region and local producers have invested in introducing novel practices (for production and processing) focused on environmental, social, and economic sustainability. Due to this, tobacco from Umbria is a leading commodity in the global tobacco industry, and it claims a high economic value. The aim of this study is then to assess if elemental and isotopic compositions can be used to protect the quality and geographical traceability of this particular tobacco. For the first time the characteristic value ranges of the stable isotope ratios of the bio-elements as a whole (δ2H, δ13C, δ15N, δ18O, and δ34S) and of the concentration of 56 macro- and micro-elements are now available, determined in Virginia Bright tobacco produced in two different areas of Italy (Umbria and Veneto), and from other worldwide geographical regions. The ranges of variability of elements and stable isotope ratios had slightly different results, according to the three geographical origins considered. In particular, Umbria samples presented significantly lower content of metals potentially dangerous for human health. The results of this first exploratory work highlight the possibility of characterizing tobacco from Umbria, and suggest widening the scope of the survey throughout Italy and foreign regions, in order to be used to describe the geographical origin of tobacco in general and verify the origin of the products on the market.

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