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Huhtamaki support the Clean Baltic Sea-project


The water of the Baltic Sea is permanently stratified according to the level of salinity. Salty seawater flowing from the North Sea is heavier and sinks to the bottom and deep basins of the Baltic Sea. The surface layer consists of water diluted by rainwater and numerous rivers flowing into the Baltic Sea.

The stratification hinders water turnover between the bottom and the surface layer. Oxygenic surface water cannot reach the deeper water layers and, and there are recurrent oxygenless periods in the deep basins of the Baltic Sea. The oxygen situation improves from time to time, about once per decade, with the help of pulses of saline water (infrequent currents of ocean water), when salty and oxygenic ocean water flows from the North Sea into the basins of the Baltic Sea, mixing with the Baltic Sea`s water layer near the bottom.

The population of the Baltic Sea is an exceptional combination of freshwater and ocean flora and fauna. The number of flora and fauna adapted to the brackish water life is small, but there may be large quantities of individual species. In comparison with the oceans, the food chains in the Baltic Sea are simple. The number of species decreases from the southern Baltic Sea to the North. The low salinity of the northern Baltic Sea, the cold winters and the sea freezing over set challenges for the adaptation of organisms. Many species in the Baltic Sea live on the extreme limits of their adaptability. The flora and fauna of the Baltic Sea is very sensitive to changes in the environment.

A total of 85 million people live in the catchment of the Baltic Sea. Over the years, the sea has been used as a dump for uncleaned community water, wastewaters from industries, agriculture and ship traffic, and different kinds of solid refuse. The bottom sediments of the Baltic Sea still contain large volumes of heavy metals and other environmental toxins. Since the 1990s, the amount of toxins and heavy metals in the fish population of the Baltic Sea decreased, but the concentrations still remain very high.

The ship traffic on the Baltic Sea is becoming more frequent all the time. This means that the risks related to oil damage increase as well. Minor cases of oil damage occur on the Baltic Sea each year, but major oil catastrophes have so far been avoided. The size of tankers operating on the Baltic Sea increases on a continuous basis. In order to prevent large-scale oil disasters, it is essential to invest in maritime safety and to improve the oil destruction readiness in case of damage.

As stowaways in ships, increased sea traffic has brought several foreign species into the Baltic Sea. Many of these invasive alien species are random visitors, but others naturalise in the Baltic Sea, and they may have substantial effects on the ecosystem and the existence of local species. Alien species are forced to compete for living space, and they might replace local species, which may change the balance between the organisms in the Baltic Sea. The spread of alien species is monitored, since they may also lead to unexpected financial effects.