铁元素调控的鱼菜共生系统氮和总磷的变化规律

Changing of Nitrogen and Total Phosphorus Regulated by Iron Content in Aquaponics System

本文研究了在鱼菜共生系统中投喂含不同浓度铁元素的饲料对水体氮、总磷的控制作用。实验共设置5个处理组和1个对照组,铁浓度分别为0mg/kg,10mg/kg,20mg/kg,40mg/kg和80mg/kg,对照组使用饲料与0mg/kg组一致,不种植蔬菜。实验证明该系统对水体产生明显的净化作用;在脱氮除磷方面也效果显著:鱼菜共生系统能够增加水体的溶氧,使水体pH值保持在正常范围,同时显著降低氨氮浓度,提高了硝态氮浓度,并使亚硝态氮浓度最终维持在较低水平;在总磷方面,总磷在水体中的分布浓度同鱼体生长情况相关性显著,同对照组相比,该系统可以将总磷降低20%左右。鱼菜共生系统为池塘养殖提供了处理水产养殖废水的新途径,是未来生态农业的新方向。

This paper analyzed the controlling effect on nitrogen, total phosphorus by stocking different feeds which had iron standard with different concentration gradient in aquaponics system. Five treatment groups and one control group were set up. Iron concentration were 0 mg/kg, 10 mg/kg, 20 mg/kg, 40 mg/kg and 80 mg/kg respectively. The control group used the same feed with 0 mg/kg group, and no vegetables were planted. The results proved that the system had obvious effect not only on purifying culturing water, but also on reducing nitrogen and phosphorus. Aquaponics system can increase the dissolved oxygen of the water, and keep pH value in the normal range. At the same time, it reduced the ammonia nitrogen concentration significantly, improved the nitrate concentration, and finally maintained the nitrate nitrogen concentration in lower level. In terms of total phosphorus, a significant correlation was found between the growth of fish and total phosphorus concentration of the water. Total phosphorus can be reduced by about 20% in this system which compared with control group. Aquaponics system provided a new way to deal with wastewater in pond aquaculture, and was also a new direction of ecological agriculture in the future.