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Chapter 5
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IntroductionThe Baltic Sea is the recipient of pollutants from the whole basin. Thus, it is of special concern for us in our efforts to improve the environment. There are many reasons to be concerned. First, the Baltic Sea is one the largest brackish water bodies in the world. This means that the Baltic Sea is neither marine nor fresh water but has salt concentrations between the two. Consequently this makes it difficult both for marine and fresh water organisms to survive and the number of species in the Baltic Sea is comparatively low. The low biodiversity probably makes it more sensitive to impacts, environmental or others. Second, the Baltic Sea is shallow, the average water depth is only about 50 m. Therefore, pollutants are not diluted as in the oceans. Moreover, the exchange of water with the ocean through the Danish straits is restricted and the half-life of the water is about 25 years. Third, the turnover of pollutants is affected by the northerly position of the Baltic Sea. A cold climate slows down the processes that degrade pollutants. On the other hand, the Baltic Sea is one of the more productive seas in the world. Fishing has always been important. Due to its short geological history it includes one of the largest archipelagoes in the world. In total there are about 25,000 island between Finland and Sweden with many dramatic and beautiful sceneries. The Baltic Sea is also one of the best monitored water bodies in the world. It was also the object of the first environmental co-operation between the former Soviet Union and the West. In 1974 the Helsinki Convention and it its Commission for the protection of the Baltic Sea (HELCOM) were created. Today there is a large investment program in the drainage area to protect the Baltic Sea. Authors of this chapter are: Lars Håkansson |
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