Journal of the Marine Biological Association of the United Kingdom

Research Article

A study on phytoplankton following ‘Volgoneft-248’ oil spill on the north-eastern coast of the Sea of Marmara

Seyfettin Taşa1 c1, Erdoğan Okuşa1, Selma Ünlüa1 and Hüsne Altioka1

a1 Institute of Marine Sciences and Management, University of Istanbul, Muskule Sok. No: 1 34116 Vefa-Istanbul, Turkey

Abstract

Following the ‘Volgoneft-248’ oil spill, phytoplankton distribution within the affected area was investigated for two years. Simultaneously measured physical variables such as salinity, temperature, Secchi disc, current speed and direction, and total petroleum hydrocarbons (TPH) were evaluated together with phytoplankton data. At the time of the accident, the TPH concentration in surface water was measured as 2.17 mg l−1 and decreased to 88.5 µg l−1 after five days. In the first sampling period, no diatoms were detected in surface water, while dinoflagellates were dominant in the phytoplankton community. The species composition of phytoplankton changed rapidly in two months and the diatoms increased in terms of abundance and diversity. This indicated that the diatoms might be more sensitive to oil pollution than the dinoflagellates. In comparison with the historical datasets, the low phytoplankton abundance following the oil spill should be considered as the small effect of oil on the phytoplankton rather than natural variability of the ecosystem. High oil concentration in the water column caused stress on the phytoplankton and influenced the species composition negatively depending on the sensitivity of groups and the natural variability of the ecosystem.

(Received May 19 2009)

(Accepted September 25 2009)

(Online publication June 30 2010)

Correspondence:

c1 Correspondence should be addressed to: S. Taş, Institute of Marine Sciences and Management, University of Istanbul, Muskule Sok. No: 1 34116 Vefa-Istanbul, Turkey email: stas@istanbul.edu.tr