工厂化养鳖——蔬菜水培系统中氮素的转化利用

Transformation and utilization of nitrogen in industrialized turtle nursery vegetable hydroponic cultivation system.

工厂化养鳖废水加适量硝酸调节后 ,用于生菜水培系统可以取得良好的净化与利用效果。系统在 2 5℃经 2周运行 ,循环液中的总有机氮有 85 %左右转化为硝态氮 ,有 9%左右被生菜吸收 ,CODcr与NH4+—N含量分别降至 10 0 mg/ L与 2 0～ 30 mg/ L以下 ,基本上达到排放标准。运行期间 ,生菜生长良好 ,重量增长率可达 2 0 %～ 2 5 %。

Addition of nitric acid in proper amount led to more effective purification of wastewater from industrialized turtle breeding ponds so that it could be successfully reutilized in hydroponic system for lettuce culture. After two week's running at 25 ℃, about 85% of total organic nitrogen in the wastewater was converted into nitrate form and about 9% was absorbed by lettuce, respectively. The quality of wastewater had then, essentially, come up to the stipulated standard for discharge. During that period lettuce plants grew satisfactorily with their weights increased by 20% 25%.