罗氏沼虾育苗水体氨氮、亚硝酸盐氮的变化规律及对幼体的影响

Changing Pattern of Nitrite-Nitrogen and Ammonia-Nitrogen in Nursery Tank Water of the Freshwater Prawn (Macrobrachium rosenbergii) and Effect on the Larvae

摘要: 用柰氏试剂法和重氮－偶氮比色法分别在罗氏沼虾工厂化育苗期间对幼体较为敏感的水中氨氮（NH3－N1）、非离子氨氮（NH3－Nm)、亚硝酸盐氮（NO2^--N)进行监测，以期找出它们的变化规律及对幼体成活率的影响。结果表明：水中NH3－Nt、NH3－Nm与NO2^--N无明显的日变化规律，但在整个育苗期间NH3－N1、NH3-Nm与NO2^--N含量的变化呈逐渐上升的趋势，其变化与管理方式有关。在幼体发育期间，水中NH3－Nm的含量超过0.11mg/L，6d时，幼体变态时间延长、存活率低。建议罗氏沼虾育苗水中的NH3－Nm含量控制在0.11mg/L以下，并通过适当调整水的pH值减少NH3－Nm的含量。

Abstract: The paper deals with the effect of ammonia-nitrogen (NH 3-N t) and nitrite-nitrogen (NO - 2-N) in the nursery water on the larvae of Macrobrachium rosenbergii , in which the concentrations of NH 3-N t and NO - 2-N were tested. The result showed: when the concentration of ionized ammonia(NH 3-N m) exceeded to 0 11 mg/L over 6 days, larval metamorphosis would be delayed causing heavy larval mortality. Daily change in the concentration of NH 3-N t and NO - 2-N was irregular, but the concentration of NH 3-N t and NO - 2-N tended to increase gradually during nursery period.