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The Origin of ‘Mare Sporco’


MASSES of a yellowish or greenish-brown gelatinous substance floating at the surface of the sea and at times colouring large areas are the cause of the phenomenon known as ‘mare sporco’. It is especially noticeable in the Adriatic, but may occur also in many other places. Numerous authorities have written on the subject, and Dr. Vito Zanon has reviewed the literature in the paper before us (“Esame di un campione di ‘Mare Sporco’ del Golfo di Fiume”. Memorie delta Pont. Accademia delle scienze—i nuovi Lincei. Series 2, vol. 15. 1931). His conclusions, based on his own observations, show that these curious masses in the water have their origin at the bottom where innumerable diatoms, usually a few definite bottom-living species, in certain circumstances by rapid reproduction give rise to a large amount of a gelatinous substance impregnated with much oxygen.

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The Origin of ‘Mare Sporco’. Nature 129, 660 (1932).

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