Culture of Marine Microalgae in Shrimp Farm Discharge Water: A Sustainable Approach to Reduce the Cost Production and Recovery of Nutrients

摘要

Marine microalgal species such as Skeletonima costatum and Chaetoceros coarctatus were cultured in Discharge Water (DW) from shrimp culture pond to recover the organic and inorganic nutrients released as waste. Total nitrogen (N), nitrate-N and total phosphorus in the DW were observed significantly higher and their mean values were 95.261, 32.6 and 11.312 mg L-1, respectively. Algal species were cultured in processed DW under 12 h light/12 h dark condition with light intensity of 6000-7000 Lux and compared with cultures made in standard Conway medium which served as a control. Cell density was obtained higher over the control by 30.1 and 20.0% in S. costatum and C. coarctatus respectively in DW. While the rate of nitrogen removal was between 42.3 and 47.2%, the phosphorus removal efficiency was 20.8 and 17.7% in S. costatum and C. coarctatus respectively. The present study inferred that, as it is a low cost technology for microalgal production as well as a mean for waste water treatment, marine microalgal culture in DW from shrimp farm will be a two in one approach towards sustainable utilization of aquatic resource.