Assessment on the efficiency of Micropterus salmoides eco-cage culture pattern in Poyang Lake District

This study introduced and analyzed Micropterus salmoides eco-cage culture pattern in Poyang Lake District for the period from 2008 to 2011. The culturing efficiency and eco-economic benefits of the pattern were assessed using an integrated approach, including on-site investigation, eco-monitoring and data analysis. The results showed that the climate, ecosystem and resources of Poyang Lake were suitable for M. salmoides culturing. The annual growth period of M. salmoides reached 8 months and more. The yearly food conversion ratios during 2008-2011 in the trial period were 8.04, 7.14, 6.11 and 5.25, respectively. While the input-output ratios were respectively 1︰1.53, 1︰1.59, 1︰1.77 and 1︰1.84, the economic benefits increased year by year for 2008-2011. The yearly energy conversion efficiencies for the period of study were respectively 0.18, 0.20, 0.24 and 0.29, and with increasing year-on-year eco-efficiency. The overall efficiency of eco-economy were 0.36, 0.42, 0.58 and 0.70, respectively, which increased by nearly one fold over the study period. It showed that a positive correlation existed between economic efficiency and eco-efficiency, with obvious eco-economic benefits. In addition, a preliminary assessment of carbon sink value and potential nitrogen and phosphorus pollution abatements showed that fixated C, N and P respectively reached 7.08 t, 1.18 t and 0.57 t under M. salmoides eco-cage culture in 2011. The cash value of carbon sink was estimated at 4 250 Yuan, which was 3.35% of the gross profit from farming. M. salmoides eco-cage culture was worth popularizing as an eco-economic strategy in place of breaking dikes or opening sluices for water storage in Poyang Lake District. It was possible to determine an appropriate aquiculture scale via scientific assessment of small wild fish resources in culture zones.