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HELCOM Indicator Fact Sheets 2004

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HELCOM indicators provide information that is considered to be crutial for mitigating environmental problems. They try to simplify complex reality and are mainly based on data obtained by HELCOM PLC and COMBINE monitoring programmes.

The indicators are presented in HELCOM Indicator Fact Sheets which are compiled by responsible institutions and approved by the  HELCOM Monitoring and Assessment Group.  The Indicator Fact Sheets for 2004 are listed in the navigation menu on the left and older ones can be found in the Indicator Fact Sheet archive.

 

The Baltic Sea continues to suffer the impacts of human activities

Baltic Sea habitats and species are threathened by eutrophication and elevated amounts of hazardous substances as a result of long-lasting human activities in the surrounding catchment area and in the sea.

Life pulsates according to water inflows

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The present state of the Baltic Sea is not only the result of the anthropogenic pressures but is also influenced hydrographic forces, such as water exchange between the Baltic Sea and the North Sea. After the major Baltic inflow in January 2003, which renewed most of the deep water in the Baltic Sea, no new major inflow has taken place and the near-bottom water in the Bornholm and eastern Gotland Basin returned back to anoxic conditions in the middle of 2004.

Eutrophication intensifies phytoplankton blooms

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Concentrations of dissolved inorganic nutrients are highest in coastal waters from the southern Belt Sea to  the inner Gulf of Finland due to land run-off. The present ratio between dissolved inorganic nitrogen and phosphorus concentrations favours blooms of nitrogen-fixing cyanobacteria.

There is no clear trend in the intensity of spring blooms since the beginning of the 1990s, although in 2004, spring blooms were more intensive in the Gulf of Finland than in the northern Baltic Proper and the Arkona Basin.

The summer blooms of cyanobacteria are highly variable both in space and time. In 2004, they were more intensive in the Gulf of Finland and Baltic Proper than in 2003. High surface water temperatures are a prerequisite for intensive blooms of toxic Nodularia species.

Heavy metals and organic pollutant still persistent in marine environment

The concentrations of heavy metals and organic pollutants in sea water are several times higher in the Baltic Sea compared to waters of the North Atlantic. As a result of efforts to reduce pollution, annual emissions of heavy metals to the air have decreased since 1990 and consequently their annual deposition onto the Baltic Sea has also halved since 1990.

Concentrations of contaminants in fish vary according to substance, species and location, but in general, the concentrations of lead and PCBs have decreased. Still the content of dioxins in the fish muscle may exceed the authorized limits set by the European Commission.

The amount of Chernobyl derived Caesium-137 in the Baltic Sea remains largely unchanged, with highest concentrations in the sediments of the Bothnian Sea and the Gulf of Finland.

Decrease in observed illegal oil spills

An increase in the number of maritime transportation during the past decade has increased the potential for an increased numbers of illegal oil discharges. Since the late 1990s ships have been required to deliver oil or oily water from the machinery spaces as well as from ballast or cargo tanks to reception facilities in ports. As of 1999, the number of observed illegal oil discharges has gradually been decreasing every year, but in 2003, still almost 300 illegal spills were detected.