RECENT DATA CONCERNING EVOLUTION OF THE EUTROPHICATION LEVEL INDICATORS IN ROMANIAN SEAWATER

摘要

Eutrophication, the most sever pollution form referring to the Romanian marine waters, began in the early 70's and reached the upper limit in the 80's. During this period, all environmental factors suffered important changes with disastrous effects on the entire ecosystem. The increasing of the nutrients and organic matter inputs by major rivers and wastewaters resulted in the increase of primary plankton production, of frequency and magnitude of the blooms' phenomenon, released chain disturbances in the ecosystem with impact on biodiversity, resources and balneal qualities. After 1990, particularly after 1995, due to the decreased nutrients input, marine waters quality was considerably improved as a proof being the diminishing of frequency and magnitude of the blooms phenomenon and the diminishing of the hypoxic areas found that the ecosystem get better. During last years, the main physical and chemical parameters of the marine ecosystem from the sampled area, recorded natural fluctuation limits for their concentrations proving a net tendency of stabilisation. The paper presents recent data as for level of the general and state indicators of the eutrophication phenomenon in Constantza area sea water, reference area for the Romanian coast. Data concerning temperature, salinity, nutrients and chlorophyll 'a' for the year 2006 were processed and compared with those for the last ten years. Data analysis demonstrated the improvement of the eutrophication phenomenon and of the Romanian sea water quality.