EUTROPHICATION IN IZMIR BAY, EASTERN AEGEAN

The polluted waters of Izmir Bay were studied to measure the variations of biochemical and physical characteristics monthly or three monthly. The spatial and temporal changes of nutrients (nitrate, nitrite, and ortho phosphate) and chlorophyll-a, in the bay were monitored during the period of February 1990-December 1992. Eutrophication of the inner bay has already started, spreading progressively to the rest of the Bay. The degree of eutrophication in the Bay was assessed. The concentration of nutrients ranged between 0.21-2.51, 0.44-4.20, 0.11-3.50 mug-at/l for PO4-P, NO3-N, NO2-N respectively. Chlorophyll-a concentration is between 0.7-39.1 mug/l and estimated primary productivity in the bay is 7-10 time higher than the offshort production in the region. Tha main reason for high primary production is the high terrestrial input. As expected total suspended solids concentrations is high, so that the water is turbidit having extremely low penetration, the average depth of secchi disk is between 2-10 m