Abstract
Phytoplankton are important primary producers in tropical coastal lagoons, with a critical role in sustaining food webs. However, most studies conducted in tropical systems with high anthropogenic influence have focused only on biomass. Water samples were collected, for phytoplankton (pigments and microscopy) and other environmental parameters, from two mangrove lagoons in São Tomé Island. The highest nutrient concentrations were observed in the mangrove of Praia das Conchas, indicating stronger nutrient inputs in this catchment area. Bottom oxygen deficiency was observed in the mangrove of Malanza, which is likely to be associated with the existence of a bridge that constrains the water exchange with the sea. Pigment analyses showed that overall chlorophyll a concentrations were low, indicating low phytoplankton biomass. The highest values were found at Praia das Conchas. It is suggested that chlorophyll a can be used as an indicator of anthropogenic pressure in this tropical system. Microscopy reveales the presence of Dinophysis sp. and Ostreopsis sp. cells, which can be harmful even at low densities. Water quality could be improved by enhancing oxygen condition in Malanza and by monitoring the occurrence of algal blooms, with potential benefits for public health and tourism.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
