Effects of Salinity and Nitrate on Coral Health Levels of Acropora sp

Changes of marine environmental conditions such as low salinity and nutrient enrichment in seawater can be mainly affected on coral health levels or can adversely cause mass coral bleaching. According to these unsuitable conditions, leading to the objective of this study is to study the effect of salinity and nitrate on coral health levels in branching coral (Acropora sp.) at the salinity vary in 15, 20, 25, and 30 psu, the concentration of nitrate vary in 20, 60, and 100 μg-N/l with triplicate experiments. The experimental results showed that 30 psu of salinity at 96 hours was unable to calculate LC50 (Lethal Concentration) because of insufficiently lower in declining coral health level or lower in motility percentage. However, the results showed that 15 psu of salinity at 96 hours was able to calculate LC50 using Probit analysis, LC50 15 psu of salinity at 96 hours was equally to 89.50 μg-N/l Moreover, high nitrate concentrations showed more paling color and stimulating to release mucus in Acropora sp.