Correction of the isotopic composition (δ13C and δ15N) of preserved Baltic and North Sea macrozoobenthos and their trophic interactions

Marine ecology progress series

Joachim W. Dippner^1¹  Jacqueline Umbricht^1²  Brian Fry^2³ 

[1] Australian Rivers Institute, Griffith University Brisbane, Queensland, Australia^2;Leibniz Institute for Baltic Sea Research Warnemünde, Seestr. 15, 18119 Rostock, Germany^1;Senckenberg am Meer, Dept. for Marine Research, 26382 Wilhelmshaven, Germany^3

关键词: Macrozoobenthos;    Preservation effects;    Stable isotopes;    Phenotype model;    North Sea;    Baltic Sea;   

DOI  :  10.3354/meps12543

学科分类：海洋学与技术

来源: Inter-Research

【 摘 要 】

To better understand food webs and the trophic relationships of marine animals studied by means of preserved material requires knowledge of the effects of preservation on the organic materials of interest. We examined the effects of formalin and ethanol preservation on the stable isotope values of carbon and nitrogen in the bivalves Mya arenaria and Tellina fabula and in the polychaetes Magelona spp. and Hediste diversicolor. Samples of these organisms were collected in the southern North Sea and the southern Baltic Sea, and were preserved with formalin, ethanol, and by freezing. The stable isotope patterns of carbon and nitrogen in the chemically preserved samples were related to those in the frozen samples. The influence of different preservation methods on the stable isotope composition was analyzed using a correction model that is independent of the molar C:N ratio. For most samples from the North Sea, significant correction factors were obtained. In contrast, none of the samples from the Baltic Sea were impacted by the preservatives with respect to their δ15N values, and, for H. diversicolor, also with respect to the δ13C values. In these cases, corrections of the δ13C and the δ15N values were not necessary. Quantitative metrics using a phenotype-based approach were computed to characterize aspects of the trophic structure of the benthic community. Phenotypic clustering in isotopic diversity indicates no competition for food between the dominant species. Our results indicate that a representative dominant mollusk and polychaete species have a higher trophic position in the Baltic Sea than in the North Sea.

【 授权许可】

Unknown