SOME SPECULATIONS ON THE NATURE OF THE PELAGIC MUCILAGE COMMUNITY OF THE NORTHERN ADRIATIC SEA

The mucilaginous material which sometimes accumulates in the northern Adriatic Sea appears to originate in marine snow. This becomes modified by progressive aggregation and consolidation with an accompanying succession of microbial associations to produce a self-maintaining community. A crucial stage must be the aggregation of marine snow in larger flocs, conditions promoting this perhaps being provided at pycnoclines or fronts. It is not clear which micro-organisms are responsible for production of the polysaccharides which form the matrix supporting the community but both diatoms and bacteria may be involved. The community shows high metabolic activity in which phototrophic and heterotrophic processes are mutually supportive and it may be regarded as a largely self-contained unspecific symbiotic system.