p. 89 - 106 EVOLUTION DES PRINCIPALES COMMUNAUTES BENTHIQUES DU SECTEUR MARIN SITUE DEVANT LES EMBOUCHURES DU DANUBE PENDANT LA PERIODE 1977-1980 Victoria Tiganus Institut Roumain de Recherches Marines Constanta Abstract Quantitative and qualitative changes in bethic communities situated close to the Danube mouths are discussed. Comparative with previous references there is a general simplification concerning structure and reduction of densities within communities such as Corbula sands transitory to muds with Spisula, the muds with Corbula-Syndesmia-Cardium association, and the muds with Mytilus.the muds