大薸及其附着物对网箱养殖水域氮磷去除效果的初步研究

A preliminary study on Pistia stratiotes and their attachments' removal efficiency of nitrogen and phosphorus in the cage culture waters

为了减少网箱养殖对水体的污染,在网箱内种植漂浮性水生植物大薸(Pistia stratiotes),并设置试验网箱和对照网箱进行对比分析。结果显示:试验网箱内的大薸及其附着物对养殖水体中氮、磷去除效果显著。养殖30 d内,大薸共去除氮201.26 g,去除磷71.53 g,附着物共去除氮5.91 g,去除磷3.01 g,附着物氮、磷去除分别占大薸氮、磷去除的2.94%和4.21%。试验网箱和传统网箱,氮的回收率分别为(41.27±1.28)%和(37.15±1.26)%,两组网箱间差异显著(P<0.05);磷的回收率分别为(31.26±1.27)%和(27.87±1.13)%,差异显著(P<0.05);氮的利用率分别为(26.32±2.32)%和(23.15±1.75)%,两组网箱间差异显著(P<0.05);磷的利用率分别为(17.21±0.51)%和(14.63±0.43)%,差异显著(P<0.05)。研究表明,大薸及其附着物通过吸收水体中的氮、磷等营养物质,可以降低网箱养殖对水体的污染。

In order to reduce the pollution of cage culture to waters,Pistia stratiotes were respectively planted inan experimental cage,comparison and analysis were conducted between the experimental cage and the control cage. The results showed that Pistia stratiotes and their attachments in the experimental cage had significant removal efficiency of nitrogen and phosphorus in the waters. 201. 26 g nitrogen and 71. 53 g phosphorus were removed by Pistia stratiotes; and 5. 91 g nitrogen and 3. 01 g phosphorus were removed by Pistia stratiotes’ attachments in the 30 day experiment. The amount of nitrogen and phosphorus removed by Pistia stratiotes’ attachments were 2. 94% and 4. 21% of those removed by Pistia stratiotes. The recovery rates of nitrogen were significantly different（P〈0. 05） in the experimental cage and the control cage,which were （41. 27±1. 28）% and （37. 15±1. 26）% respectively; and the recovery rates of phosphorus were significantly different（P〈0.05） in the experimental cage and the control cage,which were （ 31. 26 ± 1. 27）% and （ 27. 87 ± 1. 13）% respectively. The utilization rates of nitrogen were significantly different（P〈0. 05） in the experimental cage and the control cage,which were （26. 32±2. 32）% and （23. 15±1. 75）%,respectively; and the utilization rates of phosphorus were significantly different（P〈0. 05） in the experimental cage and the control cage,which were （17. 21±0. 51）% and （14. 63±0. 43）%,respectively. The result showed that Pistia stratiotes and their attachments can reduce the pollution of cage culture to waters through absorbing the nitrogen and phosphorus in the waters.