Trophic levels of small mammals: Multi-elemental composition and toxic load

The chemical compositions (25 elements) of the diet and carcass of two sympatric small mammal species (Clethrionomys glareolus and Sorex caecutiens) inhabiting near a large copper smelter and in unpolluted area (Middle Ural, Russia) have been analyzed and compared. The group of phytophages is shown to play a special role in the translocation of chemical elements over the trophic levels of mammals. Specific features of the diet and a barrier at the gastrointestinal level limit accumulation of chemical elements in the animal body. Under the same conditions, carnivores act in the mammal community as concentrators of several elements (Pb, Cd, Cr, and As), displaying increased their concentrations in the body as compared with the diet. On the other hand, the toxic load on the animal organism is independent of trophic specialization.