The State of the Mediterranean Marine and Coastal Environment

Fertilizer use and nitrogen release in the Mediterranean region

Fertilizer consumption

Slovenia

Kilograms per hectare of arable land, 2008

France

6 to 50

Croatia

50 to 100 100 to 200 More than 200 (Egypt 724) No data

Albania Bosnia and Herzegovina Montenegro

Italy

Spain

Turkey

Nitrogen release from point source

Thousand kilograms per year, 2003

Syria

Malta

Greece

Cyprus

0.3 7 240

Morocco

Lebanon

Algeria

Tunisia

Israel

Sources: UNEP Mediterranean Action Plan (MAP)/MED POL; World Bank online database

Libya

Egypt

Impacts of nutrient over-enrichment

Red tides are a problem for some Mediterranean fisheries. Fish- ing and mollusc farming in the northwestern Adriatic have been damaged by blooms of the dinoflagellate, Dinophysis spp., which causes Diarrhoetic Shellfish Poisoning (DSP). The occurrence of this organism has been responsible for temporary and pro- longed bans on the harvesting and sale of mussels in the coastal and lagoon areas of Emilia-Romagna (UNEP/MAP/MED POL 2005). Alexandrium tamarensis , a dinoflagellate that produces Paralytic Shellfish Poisoning (PSP) toxins has been observed in the northern Adriatic (UNEP/MAP/MED POL 2005). The Initial Integrated Assessment data suggest that eutrophica- tion is still a localised phenomenon in the Mediterranean Basin. Better monitoring regimes and analysis of resulting data to de- termine trends will, in the future, allow robust statements of the effect of eutrophication on the ecology, as well as on fisheries and other valuable ecosystem services (UNEP/MAP 2012).

There are numerous socio-economic impacts associated with eutrophication including: • toxicity or mortality in commercial fish and shellfish species leading to reduced catches; • loss of employment and income in fisheries related to re- duced resource base; • loss of aesthetic value resulting from algal blooms; • loss of tourism related to deteriorating water quality; • loss of employment and income related to tourism, especially sport fishing; and • loss of cultural heritage (UNEP/MAP/MED POL 2005). Most susceptible to the negative impacts of eutrophication are semi-enclosed basins, estuaries and lagoons, where excess nutri- ents are not easily dispersed (UNEP/MAP/MED POL 2005).

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HUMAN PRESSURE, STATE AND IMPACTS ON MEDITERRANEAN ECOSYSTEMS