Seasonal dynamics of the phytoplankton community in the Bay of Blanes, NW Mediterranean Sea

XXXII Trobades Científiques de la Mediterrània, Planeta Oceà - Planet Ocean, celebradas del 5 al 7 de octubre de 2016 en Maó, Menorca.-- Homenatge als Drs. Marta Estrada, Jordi Font i Jordi Salat, pioners de l'oceanografia mediterrània moderna. A tribute to Drs. Marta Estrada, Jordi Font and Jordi Salat, pioneers of modern Mediterranean oceanography.-- 1 pageThe seasonal variations of phytoplankton dynamics in surface waters of the Bay of Blanes (NW Mediterranean) were characterized during 14 years (2000 - 2014), based on biomarker pigment determinations. Pigment concentrations were determined by means of the HPLC method and the contribution of the main phytoplankton groups to total Chlorophyll a (Chla) was assessed through the application of the CHEMTAX (CHEMical TAXonomy) program. The most abundant phytoplankton groups were: Diatoms, prasinophytes, haptophytes >group 6+7>, haptophytes >group 8> and Synechococcus. Other detected groups were: core chlorophytes, dinoflagellates, cryptomonads, pelagophytes and Prochlorococcus. On average, diatoms dominated during some winter and spring months, and were abundant again in November. Prasinophytes presented the highest concentrations from December to March, decreased gradually between April and September, and increased again at the beginning of October. Synechococcus, which was practically absent during the winter period, was abundant between June and October, accounting for 39% of the total Chla in September. Haptophytes >group 6+7> showed their greatest concentration between April and October, while haptophytes >group 8> were more abundant in late autumn and winter. The variability of the phytoplankton community is discussed in relationship with the seasonal changes of environmental factors such as temperature, stratification and nutrient availability. The data showed also substantial interannual variation, highlighting the importance of time series for understanding coastal environment dynamics in a context of global changePeer Reviewe