Seasonal and spatial aspects of chlorophyll a distribution in Portuguese waters during the period 1985-1996
Bulletin of the Sea Fisheries Institute 2 (144) 1998, pp. 17-24

Maria Helena Cavaco
Instituto de Investigação das Pescas e do Mar (IPIMAR), Av. Brasilia, 1400 Lisboa, Portugal

Key words: chlorophyll, eutrophication, phytoplankton.

The data on chlorophyll a obtained along the Portuguese coast during the period 1985-1996 from 17 oceanographic cruises are synthesized and illustrated in this paper. An analysis of chlorophyll a data for the 1980s and 1990s reveals that the phytoplankton biomass did not increase and no problems associated with eutrophication are presented in the Portuguese coastal waters, despite the presence of toxic species of phytoplankton. Significant differences in chlorophyll a between coastal and oceanic stations were observed.