氨对鲤鱼苗的急性毒性

An Acute Toxicity of Ammonia on Fry of Carp

对不同规格的鲤鱼苗进行了氨的急性毒性值测定。试验将全长0．94±0．07cm、2．21±0．11cm和3．58±0．25cm三种规格的鲤鱼苗分别同3组不同浓度梯度的氨溶液接触96，J’时，结果表明：①24小时的半致死浓度（LCs。）分别为0．361、0．966和1．361mgNH3－N／L，48小时的半致死浓度分别为0．300、0．865和1．324mgNH3－N／L，96小时的半致死浓度分别为0．282、0．778和1．262mgNH3－N／L。②试验持续48小时之后，氨的急性毒性明显减弱，其致死的浓度分别为0．285、0．794和1．265mgNH3－N／L。③氨对鲤鱼苗的安全浓度范围为0．028～0．126mgNH3－N／L，且0．94±0．07cm规格的鲤鱼苗对氨最为敏感。

A series of test of acute toxicity were taken for different sizes of fry of carp. Each 3 groups of fries with size of 0. 94±0. 07cm, 2. 21 ±0. 11cm and 3. 58± 0. 25cm respectively, were treated with 3 different concentrations of ammonia for96 hours. Results showed that NH324-hour LC50 was 0. 361, 0. 966 and 0. 36mgHN3-N/L respectivly. NH348-hourLC50 was 0. 300, 0. 865 and 0. 324mgNH3-N/L respectively. After contacting ammonia for 48 hours ammonia acute toxicityobviously weaken, and its lethal threshold concentration was 0. 285, 0. 794 and 1. 265mgNH3-N/L respectively. The resultshowed that the size of 0. 94±0. 07cm carp fries were most sensitive to ammonia.