Post a comment on the text below

Excessive use of the fertilizers nitrogen and phosphorous create eutrophication of marine waters which is the accelerated, enhanced growth of phytoplankton and higher plant forms and an undesirable disturbance of the balance of organisms in the water. Land-based sources of nutrients both diffuse sources — from artificial fertilisers used in agriculture and from animal manure — and point sources from urban wastewater treatment plants, whilst reducing, are still the main sources of nutrients to waterways. Nitrogen is also released into the atmosphere and later deposited on the sea surface. Where estimates are available, they show that approximately 25 % of the nitrogen load to the sea surface is contributed as atmospheric deposition (HELCOM, 2009a).