Effects of environmental stresses on the responses of mangrove plants to spent lubricating oil

► Salinity of 5‰ and 35‰ significantly reduced growth, but stimulated O2− release and SOD activity of oil-treated Bruguiera gymnorrhiza and Aegiceras corniculatum. ► Extended flooding (24/24 h H/L tidal regime) also enhanced O2− and MDA content in both species; however, it had negligible effects on biomass reduction. ► Nutrient addition (1-6 times background levels of nitrogen and phosphorus) had no beneficial or even posed harmful effects to the seedlings.