Stable Isotope Analyses in Aquatic Ecology (a review)

Abstract

Theory and practice of analyses of stable isotopes of carbon and nitrogen for food trophic studies in aquatic ecology are regarded basing on literature, published primarily in the last decade. Methods of measuring of the stable isotope ratios, δ13 C and δ15 N, are described including those of compound specific isotope analyses. Differences in isotopic signatures between terrestrial and aquatic organisms as well as between taxa and life forms and habitats are generalized. Trophic fractionation of 15 N as the basis of quantitative estimation of trophic positions of organisms is described. Environmental factors affecting values of isotope ratios and limitations of the stable isotope method are discussed. Novel conceptions of aquatic ecology, developed on the basis of the stable isotope analyses are listed. As concluded, the stable isotopes are becoming a standard analytical tool in food web ecology. Careful use must be made of this tool, however.