the coefficient of correlation of different groups with temperature, salinity,
dissolved oxygen, C/N ratio and phosphorus revealed that representatives of the families Arnpelis-
cidae, Gammaridae and Photidae are negatively correlated with salinity. Members of the family
Corophidae showed some positive correlation with salinity. None of the groups exhibited significant
correlation with temperature or with dissolved oxygen. The effect of temperature, salinity and
dissolved oxygen on the production of gammarid amphipods was studied by multiple regression
analysis. Salinity was found to be the prominent factor controlling the abundance of gammarid
amphipods, followed by temperature and dissolved oxygen. The fitted regression was found to be
significant at the l % level (P < 0.01) only for Station 1.