The effects of Solaklı river discharge on coastal pelagic ecosystem

The Effects of Solaklı River Discharge on Coastal Pelagic Ecosystem The main aim of this study was to investigate the local ecological effects of Solaklı River discharge, South-eastern Black Sea, on coastal ecosystem. Temporal and spatial variations in primary parameters (temperature, salinity, Secchi depth values), nutrients (NO3-N, NO2-N, PO4-P, NH4-N, SİO2, Fe) and pigments (chlorophyll-a, phaeopigment, carotenoid pigment) were investigated. Samplings were conducted at 14 stations and 4 different depths and lasted around one year, August 1996 and July 1997. Effects of the freshwater run off from the Solaklı last up to 4-6 km and depth of 15 m and the influence seems to be more profound on the west part of the discharge area. Nutrient values at river discharge centre station were significantly higher than other stations. According to observed variations in study parameters it seems that it is possible to recognise four different areas from the shore through reference station at discharge centre. As a conclusion, it can be concluded that the local effects of Solaklı River discharge on coastal pelagic ecosystem seem to detrimental. Potential future changes at similar areas have been predicted establishing a simple ecological model. The region's high tendency for eutrophication was also noticed. Key Words: Nutrients, Pigments, Freshwater discharge, Antropogenic Effects, Solaklı River, Black Sea. VI