The Anoxia Phenomena

How can the dissolved oxygen be consumed in the sea water? Hypo- anoxic waters are the result of two factors: an oxygen consumption and a segregation of the water body able to prevent a new oxygen supply. Oxygen consumption is due to biomass decomposition, often accumulated in the seawater because of its fertilization; segregation conditions are instead favoured by windless weather. This was the case of the 70's and 80's hypo-anoxic events, which involved the whole North Adriatic Basin.

The growing importance fertilisation loads and the strong influence of marine circulation, have led to the need for a detailed study on past and present hypo-anoxic events that affected that whole area. This aim has been achieved on EMMA manuals: "Manual of best monitoring practice" and "The design of the monitoring system".