大黄鱼苗种对养殖水质主要污染物的急性毒性反应

Acute Toxic Effects upon the Main Pollutants of Aquaculture Water Quality on Juvenile Larimichthys crocea

摘要: 氨氮(NH₃-N)和亚硝酸盐(NO₂-N)是养殖水质的主要污染物，对养殖水产动物具有一定的毒性效应。本研究在水温(25 ± 0.5)℃，盐度23，pH 值为8.0 ± 0.1，溶解氧(DO) 大于 5.0 mg∙L^-1的条件下，研究全长90~120 mm大黄鱼(Larimichthys crocea)幼鱼对NH₃-N和NO₂-N的急性毒性反应。NH₃-N浓度梯度设置为3.00 mg∙L^-1、4.75 mg∙L^-1、7.54 mg∙L^-1、11.94 mg∙L^-1、18.93 mg∙L^-1和30.00 mg∙L^-1，NO₂-N浓度梯度设置为20.00 mg∙L^-1、34.37 mg∙L^-1、59.07 mg∙L^-1、101.55 mg∙L^-1、174.50 mg∙L^-1和299.99 mg∙L^-1。结果表明，总氨氮(NH₃-Nt)的96 h半致死浓度(96 h-LC50)为6.35 mg∙L^-1，安全浓度(CS)为0.64 mg∙L^-1；非离子氨(NH₃-Nm)的96 h-LC₅₀为0.11 mg∙L^-1，CS为0.011 mg∙L^-1；亚硝态氮(NO₂-N)的96 h-LC₅₀为45.73 mg∙L^-1，CS为4.57 mg∙L^-1。

Abstract: The ammonia nitrogen (NH₃-N) and nitrite nitrogen (NO₂-N) are the main pollutants of aquaculture water quality, which have some toxie effects on the aquatic animals. This paper studies acute toxic effects of ammonia nitrogen and nitrite nitrogen upon juvenile Larimichthys crocea with total length (90~120 mm) in (25 ± 0.5)˚C of water temperature, with a salinity of 23, pH = 8.0 ± 0.1, and dissolved oxygen (DO) more than 5.0 mg∙L^-1. The NH₃-N concentration gradient is 3.00 mg∙L^-1, 4.75 mg∙L^-1, 7.54 mg∙L^-1, 11.94 mg∙L^-1, 18.93 mg∙L^-1 and 30.00 mg∙L^-1; the NO₂-N concentration gradient is 20.00 mg∙L^-1, 34.37 mg∙L^-1, 59.07 mg∙L^-1, 101.55 mg∙L^-1, 174.50 mg∙L^-1, and 299.99 mg∙L^-1. Results show that the half lethal concentration at 96 h (96 h-LC₅₀) of total ammonia nitrogen (NH₃-Nt) is 6.35 mg/L with the safe concentration (CS) of 0.64 mg∙L^-1; 96 h-LC₅₀ of molecular ammonia (NH₃-Nm) is 0.11 mg∙L^-1 with the safe concentration (CS) of 0.011 mg∙L−1; and 96 h-LC₅₀ of nitrite nitrogen (NO₂-N) is 45.73 mg∙L^-1 with the CS of 4.57 mg∙L^-1.