Abstract:An optimal culture structure of shellfishfishalgae and its ecological environment bioremediation system were established and studied in the paper.The experimental study was carried out in a semienclosed sea area of 33.3 hm2 by net fence.The system includes three different functions culture areas:the shellfish and pearl culture area,the fish net cage culture area and the macroalgae culture area.The interculture of fish,shellfish and macro algae and pearl rearing were implemented in the demonstrative sea area.After 10 months of optimal structure culture and ecological environment bioremediation control,the water quality and biological environment of the demonstrative sea area were obviously improved.The transparency of the demonstrative sea area was significantly higher than its adjacent sea area(P<0.05),while the suspended substance content was significantly lower than its adjacent sea area(P<0.05);The concentration of total nitrogen and total phosphorus in the demonstrative sea area was increased with the cultural period of time,the high peak was in September,then it was decreased with the further cultural period of time; The biomass of plankton in the demonstrative sea area was increased with the cultural period of time,and significantly higher than its adjacent sea area(P<0.05).The marine aquaculture organisms in the demonstrative sea area grew well,the output of fishes,macroalgae and pearls respectively reached 21 365 kg,3 091.3 kg and 33.5 kg.The survival rate of pearl oyster(Pinctada martensii) reached 73.9%,the remained nucleus ratio of pearl oyster reached 49.9%,the percentage of high grade pearl was 13.7%,and the pearl layer thickness was 472 μm on average.It can be concluded that the quality of pearl was significantly improved.The photosynthetic energy efficiency reached 0.20% in the demonstrative sea area,the total energy conversion efficiency was 34.58%,the total energy consumption per unit of net yield was 2.891 9 MJ/kg.