In order to improve the aquaculture environment and reduce the sewage, six kinds of aquaculture patterns were carried out in present study. And the water physical and chemical quality, the sediment nutrients, pollutant discharge of aquaculture effluent, the environmental load, nitrogen and phosphorus utilization rate and the net fish yield were respec-tively investigated during this experiment. The results suggested that contents of total nitrogen(TN), ammonium nitrogen (NH+4), nitrate nitrogen(NO-3), nitrite nitrogen(NO-2), total phosphorus(TP), (CODMn) and suspended solid(SS) in the monoculture ponds of barracuda (T3) were significantly higher than those in the all polyculture ponds. The nitrogen and phosphorus utilization efficiency of feed in monoculture pattern was significantly lower than that in polyculture pattern, but the environmental load of nitrogen and phosphorus was significantly higher than that in polyculture pattern. The polyculture mode of allogynogenetic crucian carp (60%), barracuda (30%), silver carp and bighead carp (10%) (T5) was optimum, because their contents of organic mat-ter, TN and TP in the sediment and the amounts of TN, TP and CODMnin the discharged waste water were lowest. The nitrogen and phosphorus environment loads under the treatment of T5 were lowest, which were 51.81 kg/t and 12.84 kg/t, respectively. In addition, the nitrogen and phosphorus utilization rate of feed was highest, which was 30. 09% and 19. 15%, respectively. The feed coefficient was the smallest, and the net fish yield was the largest in the treatment of T5. So, T5 was the optimal aquaculture pattern.%为了改善养殖环境,减少排污,研究和分析了6种池塘养殖模式下水体理化指标、底质养分状况、尾水排污量、环境负荷量、氮磷利用率和鱼获物净增产量的变化,明确不同养殖模式对养殖环境负荷的影响.结果表明:单养梭鱼(T3)水体总氮、铵态氮、硝态氮、亚硝态氮、总磷、化学需氧量(CODMn)及悬浮物含量都最大,且极显著大于混养模式.单养模式氮磷利用率显著低于混养模式,但环境负荷量显著大于混养模式. 60%异育银鲫+30%梭鱼+10%鲢、鳙(T5)是最优养殖模式,其底泥中有机质、总氮、总磷含量最低,其尾水排放氮、磷、CODMn量最小.T5的氮、磷环境负荷量最小,分别为51. 81 kg/t、12. 84 kg/t,饲料的氮、磷利用率最高,分别为30. 09%、19. 15%,饵料系数最小,净增产量最大,是环境、经济较优的养殖模式.
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