Role of Salinity on Phosphorous Removal by <em>Chaetoceros muelleri</em>

The present work aims to verify the growth (estimated with optical density) of the dry biomass after proper flocculation and weighing, and removal of phosphorus by the mi-croalga Chaetoceros muelleri (Mediophyceae) at six different salinities. Cultivations were carried out with constant volume, for a period of eight days, consisting of six treatments with three repetitions each, at different salinities (30, 25, 20, 15, 10 and 5) (seawater=34). We observed that the best results were obtained when the microalgae were grown at salinity 30, that is, we observed better performances for this microalga at higher salini-ties. At this same salinity, the microalgae presented the best results of phosphorus re-moval (46.08 ± 0.67%). Regarding biomass recovery by microalgae, after drying the flocculate, the best result was obtained at salinity 25, with a final value of 3.47 ± 0.04 g dry mass L-1. Therefore C. muelleri is a promising solution for increasing demand by the blue economy with association circular economy, promoting rehabilitation of ecological sites with economic output. Thus, this work aims to evaluate the effect of salinity on phos-phorus removal using C. muelleri.