Determination of salinity and some pollution levels with geographic information systems in akyatan lagoon

In this study, Akyatan lagoon, which is among the largest wetland systems in Turkey, was characterised based on temperature, dissolved oxygen (DO), pH, alkalinity, electrical conductivity (EC), salinity, total dissolved solids (TDS), chloride (Cl-), total suspended solids (TSS), sulphate, chemical oxygen demand (COD), total phosphate (TP), ammonium, nitrite, nitrate, total coliform(TC) and fecal coliform (FC) a period between December 2007-August 2008. Seasonal and local variation were determined on a monthly basis in terms of these physical, chemical and bacteriological parameters at fifteen sampling stations previously determined. İn order to determine spatial distribution of these parameters around the lagoon, Geographic İnformation System (GIS) were used and the distribution maps were formed. Finally, these values obtained were compared to the previous studies carried out in Akyatan lagoons. As a result, pH increased, DO values did not differ significantly. Lagoon is defined as hypersalinity lagoon, because of the salinity, EC, TDS and Cl- values 1,5-2 times higher than sea water. However TSS and sulphate values were much higher those observation the drainage channels. COD was found high levels towards the west of teh lagoons as well as where the drainage channels discharge. Ammonium values observed in the drainage channel were low, however, ammonium was high in the west of the lagoon in the spring months and east of the lagoon, in the summer months. TP, nitrite, nitrate values were found generally high in the west and the drainage channal discharge point with decreasing trent in the summer months with GIS maps, the variation in the water quality of the lagoon in terms of climatic; hydrological; hydrogeological; hydrodinamic and human factors were summarized.