Hydrographic conditions and nutrient requirements during red tide in the Kaštela Bay (middle Adriatic)

Abstract

       Under the conditions of persistent and substantial input of nutrients and organic matter of anthropogenic origin to a semi-enclosed middle Adriatic basin (Kaštela Bay), summer red tide with the dominance of the species Lingulodinium polyedra (Stein) comb. nov., has become quite ordinary phenomenon in its most heavily loaded part.

      An analysis of hydrographic, chemical and biological parameters recorded at four stations during monitoring in 1989 shows surface temperature to be of great importance controlling bloom intensity. Their correlation could be described by an exponential equation applicable to all studied stations.

      Of nutrients, nitrate was an important bloom factor in the vicinity of input sources, whereas no correlation could be established at the most offshore station.