Marine biodiversity: life in seas under threat
Published: 17 Mar 2010
Climate change, pollution, acidification, over-exploitation of fish stocks, invasive alien species all threaten life in our seas and consequently the services we obtain from them. The European Environment Agency”™s (EEA) new short assessment of marine biodiversity takes a closer look at the “˜less known half”™ of EU territory.
It is not only about seafood or a romantic sunset, our oceans are essential to us both ecologically and economically. They regulate our climate, produce oxygen and remove carbon from the atmosphere through processes such as photosynthesis. They are also home to an incredible number of species, with many new ones discovered on a regular basis, living in almost unimaginable settings. Today, biodiversity in Europe”™s seas and oceans faces an unprecedented range of pressures and require urgent action.
The key threats are known
.Â Â Â eutrophication “” increased concentrations of chemical nutrients, resulting mainly from intensive agriculture on land, continue to be a major problem affecting most European seas;
.Â Â Â pollution “” although concentrations of hazardous substances are decreasing, their persistence and the large amounts already released mean that negative effects will continue for decades;
.Â Â Â climate change “” impacts on marine biodiversity and ecosystems are becoming more and more obvious: sea surface temperatures and sea levels are rising; sea-ice cover is decreasing; and the chemical, physical and biological characteristics of the sea are changing;
.Â Â Â invasive alien species “” combined with other pressures such as overfishing, acidification and climate change, introduction of invasive alien species can alter entire ecosystems.
Marine protected areas are effective
European marine biodiversity is primarily protected by establishing Natura 2000 sites under the Habitats and Birds Directives but there are serious delays in identifying areas and even longer delays in assessing their status. Evidence suggests that marine protected areas support marine biodiversity and fisheries, and that the extent of recovery increases with the age and size of the protected area.