EXPERIMENT TO DECIPHER THE EFFECT OF HEAVY METAL CADMIUM ON COASTALBENTHIC FORAMINIFER PARAROTALLANIPPONICA (ASANO)

摘要

The response of benthic foraminifer Pararotalia nipponica to heavy metal cadmium is observed in laboratory experiment., The results indicate that under a given set of conditions, heavy metal cadmium is deleterious to benthic foraminifera. Gradual increase in cadmium (Cd) concentration mainly affected normal growth and caused morphological abnormalities which were consistent from 4 μg/l to 14 μg/1. The intensity of deformation was severe exhibiting a peculiar change in coiling direction with increase in cadmium concentration. The presence of >50% deformed specimens at the lowest cadmium concentration (2 μg/l) indicates that the threshold of Cd concentration which is detrimental to P. nipponica is <2 μg/l.