Journal of the Marine Biological Association of India

Volume 13 Issue 2

Hydrography of the Coringa River of the Gautami-Godavari estuarine system.

D. V. Rama Sarma and P. N. Ganapathi

The Coringa River is an important part of the Godavari estuarine system connecting the Gautami- Godavari and the Kakinada bay. The river is flanked by extensive mangrove swamps whch are traversed by a number of tidal creeks. The variations in the physical and chemical parameters such as transparency, temperature, salinity, dissolved oxygen, nitrite, inorganic phosphate and silicate were found to be primarily influences by the tidal currents from the Gautami- Godavari and Kakinda Bay ends of the river. In addition, the drainage from the irrigation canals emptying into the middle portion of the river was also found to affect the hydrological conditions.

The Coringa River is characterised by low transparency of the water through a greater part of the year; prolonged period of freshwater in undation; salt-water incursion from both the ends beginning from November; steep horizontal and vertical gradients in salinity and temperature, high nutrient concentration during the summer season; and inflow and outflow of water during the flood and ebb phases of the tides respectively.

The possible role of mangrove swamps in the regeneration and replenishment o fthe nutrients is commented on.

Date : 30-12-1971