A STUDY ON JAPANESE EEL ANGUILLA JAPONICA LOW-CARBON AQUACULTURE TECHNIQUE OF BIOFILM IN-SITU BIOREMEDIATION IN EARTHERN POND
日本鳗鲡(Anguilla japonica)土池生物膜原位修复低碳养殖技术的研究

To study the effect of saving water and reducing pollution, culture benefit and mechanism of the technique of biofilm in-situ bioremediation of earthern pond ecosystem for eel intensive culture, the trial was implemented, which included the treatment with biofilm purifying water bar, set in earthern ponds for biofilm developed, and the control without the bar, and used 12 freshwater earthern ponds with Japanese eel (Anguilla japonica) intensively cultivating. The results showed, during the 172 days eel cultivation trial, the treatment saved 78% water exchanged than the control significantly (P<0.01); the concentrations of TAN, NO2-N, CODMn, soluble reactive phosphate and turbidity in the treatment were significantly decreased at 31.7%, 49.7%, 29.6%, 24.2% and 26.2% than the control respectively (P<0.01); the variety range of algae density and blue algae relative density in the treatment were significantly decreased at 58.8% and 52.6% than the control respectively (P<0.01); the treatment increased net yield, eel harvest size and growth rate at 38%, 22.7% and 27.1% respectively (P<0.01), and decreased feed conversion rate at 14.2% (P<0.01) than the control; the treatment increased profit about 772.5 thousand yuan per hectare than the control. In conclusion, pond low-carbon aquaculture technique of biofilm in-situ bioremediation had advantages, such as low cost, saving water and reducing pollution, increasing yield and profit, convenient operation and easy for extension. Therefore, the technique would have a great extension prospect.