Tuesday 1 March 2011

The Tsesis Oil Spill: Its Impact on the Coastal Ecosystem of the Baltic Sea

Linden, O | Elmgren, R | Boehm, P
Ambio Vol 8, No 6, p 244-253, 1979. 13 Fig, 26 Ref. 

The Tsesis study describes an attempt to investigate the full spectrum of effects of an oil spill on the ecosystem of a rather sheltered coastal archipelago in the atidal brackish Baltic Sea. The study demonstrated a number of effects of oil on various types of organisms. In general, however, the impact seems to have been of relatively short-term nature in the pelagic system, a conclusion supported also by the results of the investigations following the Torrey Canyon and Argo Merchant accidents. Increases in primary production among phytoplankton in impacted areas have been observed earlier. The stimulation of primary production in the area affected by the Tsesis oil spill is probably related primarily to the higher phytoplankton biomass in the area. The observed decrease of zooplankton in the vicinity of the ship was undoubtedly due to the acute toxic effects of the oil. The results of the investigations of the effects of the Tsesis oil on littoral communities indicate severe acute effects on all major faunal groups. These results together with results from a study of a very similar spill in the Stockholm archipelago suggest that complete recovery of a littoral community under these circumstances will take two to three years. (Sinha - OEIS)

Descriptors: Oil spills | Water pollution effects | Ecosystems | Outer Continental Shelf | Baltic Sea | Coasts | Environmental effects | Tsesis oil spill | Soviet tankers