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In recent years, marine aquacultures have developed rapidly because of sharp drop in sea fishery resources and fast increase of need on sea food, especially shrimp aquaculture, as a major cultured model, has gotten a greater development, and has become a mainstay industry. But shrimp cultural system is a manual-controlling ecological system, in which the residual feed and faeces make the cultural environment worse. Therefore, it is very necessary to develop an integrated microbial remediation technology for intensive shrimp pond culture.Immobilization technology has been widely used in mariculture environment remediation, and the carrier is a very important factor affecting the purifying effect. In this study, two kinds of immobilized carriers, coral stone and bamboo, were chosen and their purifying ability were compared with ceramic which was widely used in China. The results showed that the purifying effect of coral stone and bamboo to the ammonia nitrogen, nitrite nitrogen and organic matters was better than ceramic, especially for COD removal efficiency.Seawater is a high-salinity, oligotrophic environment, and the added exogenous bacteria may be difficult to become dominant because of shortage of some nutrients or the unbalance of various nutrients, thus, purifying effect could not be ideal. To solve the above problem, a series of studies on the effect of adding nutrients to the purification effect of microorganism products were carried out, and the relationship between the ratio of carbon, nitrogen and phosphate and the removal rates of COD, NH4-N and NO2-N were calculated, and the mathematics models were set up. The results showed that the purification ability of microorganism products was significantly improved by adding suitable nutrients. The removal rates for COD, NH4-N and NO2-N got the highest,97.07%,96.88% and 93.41%, when the ratio of C:N:P was 62.5:4.85:1,37.5:4.51:1 and 25:2.97:1, respectively. The relationship between the glucose and phosphate concentrations and COD, NH4-N and NO2-N removal rates could be described by quadratic equations.After immobilized carriers were selected and the nutritional conditions required by exogenous bacteria were optmized, the impact factors, the substrate concentration and hydraulic loading. of two stage biologically aerated filter (BAF) operation were explored through the simulatiing experiments. The effect of hydraulic loading on purification effect of the bio-filter under different substrate concentration was carried out, and a correlation model was established. The optimal substrate concentrations for COD, NH4-N and NO2-N removing were 20mg/L,0.5mg/L and 1mg/L, respectively; and the best hydraulic loading was 50m3/(m3·d). Under different substrate concentrations, the relationship between the hydraulic loading and the removal rates of these three kinds of pollutants was in line with quadratic relations, that is V=aH2 +bH+c.In situ shrimp culture system was also performed, a connected two-stage bio-filter was set up, composed of an upward flow aerated bio-filter filled with three-layer carriers and a horizontal flow bio-filter. The purifying effect was monitored for two consecutive months. Results indicated that the water from the bio-filter could meet the state standards for aquaculture.In addition, at the end of shrimp culture, the shrimp pond sludge at the bottom was collected, and composting treatment was introduced into sediment treatment firstly. The affect factors, the moisture content and conditioning agent (sand), were studied. And the mathematic model was established. It provided a sound theoretical basis for future pond sediments treatment.In this study, immobilized carriers screening, nutrients ratio that the exogenous bacteria required, biological filter of indoor simulation and in situ application and compost processing of pond sediment were studied. A set of integrated microbial remediation technologies suitable for intensive shrimp culture were established, these techniques were combined with large algae, shellfish aquaculture and jet foam separator to build a set of integrated environmental remediation technology and cultural mode for intensive shrimp pond-culture, which supplied theoretical and practical basis for the realization of self-remediation function of the green and efficient shrimp pond-culture
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