Evaluation of the pollution status after the rehabilitation works and the anthropogenic pressure factors of the Golden Horn Estuary (Sea of Marmara)

Evaluation of the pollution status after the rehabilitation works and the anthropogenic pressure factors of the Golden Horn Estuary (Sea of Marmara)

Hüsne Altıok, Ahsen Yüksek, Seyfettin Taş, Fuat Dursun, Selma Ünlü, Nuray Çağlar, Abdullah Aksu, Ömer S.Taşkın, Yaprak Gürkan, İ. Destan Öztürk, Fatih M. Adatepe

ORCID ID(s): H.A.0000-0003-0362-4938; A.Y. 0000-0001-7949-3001; S.T. 0000-0002-4660-3937; F.D. 0000-0002-7729-5893; S.Ü. 0000-0002-9156-4332; N.Ç. 0000-0001-7608-6339; A.A. 0000-0003-1368-5689. Ö.S.T. 0000-0002-6284-1337; Y.G. 0000-0002-9076-1828; İ.D.Ö. 0000-0001-8915-6236; F.M.A. 0000-0002-9523-6301

Institute of Marine Sciences and Management, Istanbul University, 34134 Istanbul, TÜRKİYE


In this review article, the oceanographic and ecosystem characteristics and pollution status of the Golden Horn Estuary (GHE) was evaluated during and after remediation in terms of physicochemical parameters, nutrients, phytoplankton blooms, ichthyoplankton and pollutants. The changes in the Golden Horn ecosystem and the distribution trends of the toxic and persistent pollutants have been revealed by assessing the information obtained from various research and projects carried out in the Golden Horn for about 20 years. As a result of the rehabilitation works, the secchi disc depth, total suspended sediments, dissolved oxygen, nutrients and partially petroleum hydrocarbon values improved and the GHE started to show the characteristics of “coastal transition water”. Accordingly, it was determined that the pollution continued in the shallow inner part of the Valide Sultan station, while a significant improvement has been reported between Galata and Unkapanı Bridges. Recently, GHE has started to display “marine water” characteristics in terms of fish eggs and larvae composition. Oceanographic and ecosystem characteristics of the GHE and current pollution assessment have revealed that the most important pressure factors on the area are the metropolitan region, geographical features and dredging activities. In order to reduce the effect of these pressures, some precautions have been suggested like advanced treatment of discharges, prevention of leakage water discharges, and dredging of bottom sediment material.

 Keywords: Persistent pollutants, phytoplankton blooms, toxins, ichthyoplankton, water quality, Golden Horn Estuary

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