Variation of phytoplankton community structure in Quang Ngai coastal waters during 2015–2019

Phytoplankton in coastal waters are important for the evaluation of either biodiversity or environmental impacts because this highly vulnerable ecosystem. Seasonal and annual changes phytoplankton community structure Quang Ngai during period 2015 to 2019 were analyzed assess diversity reveal possible causes these changes. A total 366 taxa belonging 10 classes identified throughout present study. The highest species number was found with 295 taxa, followed by those (247), 2017 (185), 2018 (99). Ly Son transect showed most stable communities both dry rainy seasons, whereas stations coast revealed high variability communities. All indices including Margalef, Pielou, Shannon, Simpson did not reflect well differences average values but a certain degree variances, indicating impacts. During study time, there blooms diatom Skeletonema spp. Pseudo-nitzschia 2019. Analysis diatoms index, Centric/Pennate ratio, indicated that eutrophic status decreasing trend from area island This research built up fundamental data on province. index would be used as indicators their provided warning eutrophication water surrounding island.