Role of Sewage Discharge on the Diversity and Distribution of Zooplankton in the Mahanadi River,India

Abstract

Zooplankton forms an important component of fish fries and helps to transfer energy from primary to secondary and tertiary levels in a food chain. Realizing the paucity of patent literature on the zooplankton population of sewage-fed river Mahanadi, studies were undertaken to assess the seasonal dynamics of zooplankton populations and nutrient status of water for a period of one year covering three seasons. Zooplankton population and water analysis was performed using standard procedure. Maximum population density was observed in the winter season followed by summer and lastly rainy. Higher zooplankton populations were encountered in Sikharpur (site IV). They corresponded to the fluctuation of prevailing conductivity, turbidity, dissolved oxygen, better organic load and chemical oxygen demand content of the said habitat. A total of 14 species belonging to six different groups were recorded during the study period. Lower concentration of zooplankton at Sikharpur site indicates polluted zone of the river. Our findings highlighted the deterioration of water quality in the river due to industrialization and human activities. Proper biological and chemical treatment of domestic sewage and industrial effluents before discharge to river system is suggested.