Wyniki wyszukiwania - Biblioteka Nauki

Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl

Ograniczanie wyników

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: stable isotope analysis

Sortuj według:

Ogranicz wyniki do:

Correlation between δ13C and δ15N in flying fish (Exocoetus volitans) muscle and scales from the South China Sea

100%

Wu L. , Xu L. , Sun J. , Wang X. , Wei Y. , Li Y. , Liu X.

tom Vol. 46, No. 3

307--313

We collected flying fish (Exocoetus volitans) from the South China Sea to determine whether fish scale isotope values correlate with those from muscle, and discuss relevant eco-environmental implications. A significant positive correlation was determined between fish scales and muscle δ13C and δ15N, rendering a fish scale an alternative to muscle tissue for stable isotope analysis. However, muscle and scale isotopic offsets should be fully considered when using δ13C and δ15N to analyze the actual trophic level of fish and their food source. The average offsets of δ13C and δ15N between muscles and scales are -2.1 ± 0.5‰ and 2.3 ± 0.6‰, respectively, though these values vary slightly with fish mass. Weak correlations were found between δ13C and δ15N, both in the flying fish muscle and scales, suggesting that other factors are influencing δ13C and δ15N. Fish δ15N also correlates with the size of individuals, while δ13C reflects the marine habitat. Based on our data, it appears that more eco-environmental processes can be revealed from modern or ancient flying fish scales.

The use of stable isotope analyses in freshwater ecology: current awareness

58%

Grey J.

nr 4

Ecological research using stable isotopes has progressed rapidly during the last 20 years and although more studies are including the addition of isotopically labelled compounds at tracer levels, the overwhelming majority rely on measurements of natural abundance ratios. Access to isotope ratio mass spectrometry has increased, spurred on by awareness of the techniques and increasing demand, and consequently cost of sample analysis has dropped. Today stable isotopes of carbon (¹³C/¹²C), nitrogen (¹⁵N/¹⁴N), sulphur (³⁴S/³²S), oxygen (¹⁸O/¹⁶O), and hydrogen (²H/¹H) can be determined routinely. Perhaps one of the most appealing attributes of isotopic signatures is their potential use to find patterns and determine mechanisms across a range of scales from the molecular level through to characterising whole food webs, reconstructing palaeoenvironments, tracing nutrient fluxes between ecosystems and identifying subsidies, or migrations of organisms. Ecologists from every discipline who are unlikely to have been trained as isotope chemists have added stable isotope analysis (SIA) to their “toolbox”, but often increasing use leads to increasing abuse. The usefulness of SIA arises from predictable physical and enzymatic-based discrimination between biological and non-biological materials leading to different isotopic compositions. Without some ecological understanding of these, interpretation of isotope-derived data can often be flawed. Here, I explore how SIA recently has been used for research in aquatic ecology, reviewing how some of these techniques have allowed elucidation of key processes in aquatic systems such as the contribution of allochthony to lake food webs, and discuss the “state of the art”. Included are some thoughts on where our knowledge in aquatic ecology remains deficient and how continued development and future application of SIA and interdisciplinary methodologies may be applied.