Resumen de Proliferacions algals nocives a la costa catalana
This chapter reviews a problem – that of harmful algal bloom (HAB) occurrence onthe Catalan coast – which has been gaining prominence in recent decades. Some generalconcepts related to HAB formation and effects are explained and the main harmfulphenomena registered on the Catalan coast are discussed. Among the most frequenttoxic species are some dinoflagellates of the genus Dinophysis, producers of diarrheticshellfish poisoning, which may be responsible for closures of exploitation areas ofbivalves (which accumulate toxins when they consume the microalgae). Alexandriumminutum and A. pacificum give rise to recurrent blooms in confined areas such as theports of Arenys (A. minutum) or of Tarragona (A. pacificum) and produce toxins thatcause the so-called paralytic shellfish poisoning. Another Alexandrium species, A.taylori, is not toxic but its accumulation causes brownish spots on several Catalanbeaches, with the consequent economic and aesthetic damage. Ostreopsis cf. ovataforms mucilaginous aggregates on macroalgae and marine phanerogams, corals, orabiotic substrates (sand, rocks) and their summer proliferations have been associatedwith respiratory and skin irritation in people exposed to marine aerosols on somebeaches of Catalonia and elsewhere in the Mediterranean. There has been an increase inPAN records both in the Catalan countries and in other parts of the world. There areseveral causes, including natural and anthropogenic changes that have originated a realincrease of these phenomena, and the greater use and occupation of the coast togetherwith the improvement of detection and monitoring systems. In the case of Catalonia,one of the main factors that seems to have contributed to the increase of PAN,especially with regard to the genus Alexandrium, has been the multiplication ofconfined water areas associated with the building of ports and other maritimeinfrastructures.
