Chemical and biological analyses of bay sediment where magnesium oxide compounds are applied

Abstract

Three magnesium compounds, MgO2, MgO, and Mg(OH)2, which are supposed to supply oxygen continuously, were applied onto contaminated bay sediment and its ecology in order to activate the local microbial flora. Those compounds were found to reduce chemical oxygen demand (COD), total nitrogen (T-N), and total phosphorus (T-P). Magnesium oxide, in particular, reduced COD by 30% and T-N and T-P considerably. All compounds also suppressed the release of pollutants in the order MgO2, MgO, and Mg(OH)2. Analysis of microbial flora showed that the microbial group treated by MgO2 and Mg(OH)2 was predictably stable; meanwhile, that treated by MgO increased the number of species, but decreased the total number of microorganisms. ? 2014 Korean Society of Environmental Engineers.