海水稻田湿地对半咸水对虾养殖池塘水环境的净化作用研究

Purification effect of searice paddy field on brackish water environment of shrimp culture

为探索海水稻-对虾塘田生态联作模式中稻田湿地的水环境净化作用,分别开展了稻田净化单元在夏、冬季对虾养殖周期的尾水处理效果研究。夏季试验中,对虾养殖尾水经不同种植密度的海水稻和常规水稻稻田净化处理,6周后各处理尾水中氨氮(NH_(4)^(+)-N)、硝酸盐氮(NO_(3)^(-)-N)、亚硝酸盐氮(NO_(2)-N)、总磷(TP)和化学需氧量(COD浓度)均大幅下降,单倍密度海水稻稻田净化效果最好,对应去除率分别为81.6%、68.2%、63.7%、91.0%和29.7%,均显著高于无水稻对照处理(P<0.05),其中-N及可溶性无机氮去除率显著高于常规水稻处理(P<0.05);冬季试验中,塘田联作塘海水稻收割,池塘进入冬棚养殖,水体中NH_(4)^(+)-N、NO_(3)^(-)-N、可溶性无机氮和总悬浮颗粒物(TPM)的平均质量浓度分别较单养对照池塘降低了51.5%、40%、36.7%和11.2%(P<0.05);NO_(3)^(-)-N、TP、COD、颗粒有机物(POM)、颗粒无机物(PIM)的平均质量浓度与对照池塘无显著性差异(P>0.05)。研究结果表明,海水稻稻田在水稻生长季与非生长季具有相似作用,均具备一定的水质净化能力,有利于维持对虾生长所需的良好水质环境。

In order to explore the water purification effect of paddy field in the combined pond-paddy field farming system,we analyzed the biofiltration ability of sea rice paddy field in two shrimp culture seasonS(Summer and winter).In the summer trial,the tail water of shrimp culture waSpurified by sea rice and common rice paddy fieldSwith different planting densities,and the purification efficiency of sea rice paddy fieldSwith standard planting density waSthe highest.After six weeks,the removal rateSof ammonia nitrogen,nitrate nitrogen,nitrite nitrogen,total phosphoruSand chemical oxygen demand in standard sea rice treatment were 81.6%,68.2%,63.7%,91.0%and 29.7%,respectively,which were significantly higher than those in the control treatment(P<0.05),and the removal rateSof ammonia nitrogen and total inorganic nitrogen were significantly higher than those in the common rice treatment(P<0.05).In the winter trial,sea rice waSharvested in the shrimp-rice pond,the average concentrationSof ammonia nitrogen,nitrite nitrogen,total inorganic nitrogen and total particulate matter in the shrimp-rice pondSdecreased by 51.5%,40%,36.7%and 11.2%,respectively,compared with the shrimp monoculture pondS(P<0.05).The average concentrationSof nitrate nitrogen,total phosphoruSand chemical oxygen demand,particulate organic matter and particulate inorganic matter were not significantly different from those in monoculture pondS(P>0.05).The resultSshow that the sea rice paddy field haScertain purification ability in both rice growing season and non-growing season,which helpSto maintain a good water environment for shrimp growth.