Résumé
The size, composition and distribution of particles in the water column were surveyed in a shallow area (1 m depth) of a tropical lagoon (Côte d'Ivoire) during a sequence of wind-induced resuspension. Water samples were collected hourly near the surface during one tidal cycle. Three characteristic periods were distinguished: a calm period with low wind speed (average 1.2 m s−1 a windy period with wind speed >3 m−1 s (range between 4 and 6 m s−1) inducing sediment resuspension and a relaxation period during the decrease of wind velocity. From the analysis of several parameters (particle size and volume, bacteria. pico- and nanophytoplankton, ciliates and detritus), sediment resuspension caused a regular injection of particles from the bed. The finest particles (1.5–6 μm: chlorophytes such as Chiorella spp., picocyanobacteria such as Synechococcus) were the first to be affected by wind-induced turbulence, whereas large particles (6–12 μm: diatoms. cyanobacteria such as Lyngbia spp.) were dispersed into the water column at the highest wind speed. The fate of the different seston components differed according to their size. Therefore, wind-induced resuspension could greatly influence the food web organization through the quantity, quality and size of edible particles available at a given time.