UPTAKE OF CADMIUM BY THE EELGRASS ZOSTERA-MARINA

The uptake of cadmium by the shoots of Zostera marina L. (eelgrass) was examined in the laboratory. Experiments were carried out in experimental chambers which allowed the separation of the leaves from the root-rhizome portions of intact shoots. Cadmium uptake by the root-rhizome portions over 24 h was directly related to substrate cadmium concentration (1.0, 5.0 and 10.0 μg Cd ml-1) and varied from 6.5 to 30.0 μg Cd g-1. Cadmium uptake by the root-rhizomes and the leaves in a substrate concentration of 1 μg Cd ml-1 was also related to exposure times (24, 48 and 72 h). Maximum uptake by the root-rhizomes and the leaves was observed after 72 h at a substrate concentration of 1 μg Cd ml-1 and was equivalent to 48 and 94 μg Cd g-1, respectively. Translocation of cadmium from the leaves to the root-rhizomes was observed after 24 h, and at the end of 72 h was equivalent to 27% of the total leaf uptake. No cadmium movement from the root-rhizomes to the leaves was detected. © 1979 Springer-Verlag.