Agriculture is the largest non-point source of pollutants in the Mediterranean (UNEP/MAP 2011). Agriculture-related nutrients enter the sea through groundwater, lakes, wetlands, and rivers. Nitrogen consumption per surface unit of arable land is highest in countries of the northern watershed, with the exception of Bosnia-Herzegovina and Albania. In contrast, point-source release is highest on the eastern coast of the Adriatic. Other point sources of nitrogen are concentrated in the Ebro watershed, the eastern coast of the Levantine Basin and the western coast of Tunisia.
From collection: State of the Mediterranean Marine and Coastal Environment