Seasonal variation in mercury and food web biomagnification in Lake Ontario, Canada.

摘要: Seasonal variation in mercury (Hg) concentrations and food web structure was assessed for eastern Lake Ontario. Hg concentrations, measured 6 species of invertebrates 8 fishes, tended to be highest the spring lowest summer most biota. Yellow perch (Perca flavescens) exhibited significant ontogenetic shifts diet Hg, although such patterns were not evident other species. Food structure, as indicated by stable isotope values (δ(15)N, δ(13)C) static. Log-transformed data strongly consistently correlated with δ(15)N whole each three seasons (slopes, 0.17-0.24) across entire year (slope, 0.2). While significantly different between seasons, regression slope are still consistent published global biomagnification rates. Our results indicate that assessment trends Great Lakes must take into account seasonal time sampling.