The effects of nitrogen and phosphorus nutrients on the bioremediation of oil-contaminated waters by Gracilariopsis persica in the coastal areas of Bandar Abbas

This study investigated the influence of nitrogen and phosphorus on the bioremediation of crude oil by Gracilariopsis persica in littoral zone waters. In order to determine the role of nitrogen in bioremediation, urea, ammonium, and nitrate were used with and without phosphorus, with the result that nitrogen had no significant effect on the degradation of oil by Gracilariopsis persica in the littoral zone. Nearly 90 % of the crude oil used in this study was degraded by treatments with added phosphorus and nitrogen. A significant increase in the degradation of oil-contaminated water was observed after the application of phosphorus. Comparatively to the application of phosphorus alone, nitrogen and phosphorus together increased the rate of biodegradation by the algal species. Based on the results of the study, nitrogen and phosphorus have complementary effects on the bioremediation of oil by Gracilariopsis persica. [Display omitted] •The nitrogen concentration in the littoral zone did not significantly affect the degradation of oil by G. persica.•Oil-contaminated water was significantly degraded with the addition of phosphorus.•The application of phosphorus alone, simultaneous application of nitrogen and phosphorus increased the rate of biodegradation of oil by G. persica.•About 90 % of the crude oil in the spill was decomposed by treatments containing phosphorus and nitrogen.•Nitrogen and phosphorus have complementary effects on G. persica's ability to degrade oil.