Food Chain Relationships of Copper and Cadmium in Contaminated Grassland Ecosystems

Abstract

An analysis of the distribution of copper and cadmium between components of a contaminated grassland ecosystem has established a much greater food chain transfer potential for cadmium than for copper. Almost regardless of the degree of environmental contamination, the retention of copper in mammalian systems is regulated by absorption-excretion equilibria that adapt to maintain a homeostatic situation. However, accumulation of copper does occur in some groups of terrestrial invertebrates in relation to dietary concentrations of the metal. No body retention control mechanisms were evident in mammals or invertebrates in respect of cadmium, a non-essential trace element whose distribution is characterised by preferential accumulation in the liver and kidney target organs of mammals, and by food chain concentration through predator-prey relationships.