Lyngbya majuscula blooms in an enclosed marine environment

Abstract

Cyanobacterial blooms are a cause of concern because of their potential impacts on the marine environment. In Sentosa Cove, Singapore, Lyngbya majuscula blooms appeared regularly in the highly enclosed boat canals traversing the seafront residential development. This study investigated whether sediments resuspended by physical disturbance liberated nutrients that contribute to the blooms. Sediment resuspension events were mimicked in containers of sediment collected from the canals. Lyngbya majuscula that were incubated in containers with resuspended sediment attained greater biomass than those in filtered seawater only. Levels of iron, phosphates and nitrites in seawater with resuspended sediments were significantly higher than in those without. The results indicate that recurrent L. majuscula blooms in Sentosa Cove could be attributed to nutrient loading from sediment resuspension.