The seas surrounding Istanbul exposes to serious pollution problems caused by domestic and industrial wastes. Especially, pathogenic microorganisms and chemical materials, which found in domestic and industrial wastes that introduce to the sea via Ayamama stream forms a potential risk for humans and living organisms inhabiting marine environment. In this sense, in the current study seawater samples were taken from Ayamama stream’s discharge point and from around of its six different areas every 15 days, and were examined in terms of bacteria such as faecal coliform, total coliform, faecal streptococci, Salmonella spp. and total mezophilic aerobic heterotrophic bacteria from May 2007 to April 2008.
Furthermore, it has been investigated that whether there is a relationship between the existence of pollution indicator bacteria which were used in order to examine seawater quality and enviromental factors such as seawater temperature, salinity, pH, the amount of dissolved oxygen that the adaptation of bacteria to seawater and to each other.
It is found that in all of the seven areas from which samples were taken, five groups of bacteria proliferate simultaneously, and that numerical consequences found are over seawater quality standards. It is found that the area in the best condition is the 6th station and the worst one is 1st station. Also, it is determined that the number of indicator bacteria show difference depending on months and seasons. Although, along the study period, considerable changes has been done at climate condition and environmental parameters at Ayamama stream’s discharge point, it has been revealed that bacteriological pollution is constant. Furthermore, a hierarchical ascendant cluster analysis was used to classify the sampling stations into similar grups. Dendograms obtained from cluster analysis has revealed that 3th, 4th, 5th and 7th stations were similar at the first level in terms of the number of faecal coliform, total coliform, faecal streptococci and Salmonella spp. However, 6th station was similar at the second level with 3th, 4th, 5th and 7th stations.
Statistical analysis showed that there is no significant relationship among seawater temperature, dissolved oxygen amount and seawater salinity and the number of indicator bacteria. However, it has been determined that there is a significant relationship between the number of indicator bacteria and the presence of Salmonella spp.