Abstract
Cation-exchange capacity (CEC), ignition loss, clay fraction and heavy metal content were measured in bottom sediments from the Nagara River, and the data were subjected to multiple regression analysis.
The average CEC of sediments in the middle and lower reach of the river were 3.23 and 10.5 meq/100 g respectively. Good correlations were found between CEC and ignition loss or clay fraction, and multiple correlation coefficients were more than 0.92 among them. From regression equations it was possible to estimate the CEC of ignition loss and clay fraction, and they were 0.41-1.0 meq/g and 0.36-0.49 meq/g respectively. Relative contribution to CEC was comparatively more dependent on clay fraction than ignition loss. A good relationship was observed between CEC and heavy metal content at every sampling station.
