Saline-alkaline water resources are plentiful in China, but fisheries production in these waters is relatively low due to the lack of suitable culture species adapted to different saline-alkaline water characteristics.Triplophysa dalaica(Order Cypriniformes and Family Cobitidae) lives in Dali Lake where salinity reaches 6% and alkalinity is as high as 53.57 mmol/L. This species has a high tolerance to high salinity and alkalinity and could be a good aquaculture species for high salinity-alkalinity water. However, little is known about the tolerance limits of cobitid fish compared with those of other freshwater fish species. Thus, the tolerance of three cobitid fish species, such as Misgurnus mohoity Dybowsky,Paramisgurnus dabryanus Sauvage, and T. dalaica, to salinity and alkalinity were investigated by 96 h one-way acute toxicity tests and a uniform orthogonal test in this study. The results showed that the 24 h- and 96 h-LC50 values for salinity in M. mohoity,P. dabryanus, and T. dalaicawere 15.64 g/L, 13.58 g/L, and 15.43 g/L and 14.18 g/L, 14.00 g/L, and 11.57 g/L, respectively, with safe concentrations of 4.12 g/L, 4.03 g/L, and 3.74 g/L respectively. The degree of salinity tolerance was M. mohoity>P. dabryanus>T. dalaica.The 24 h- and 96 h-LC50 values for carbonate-alkalinity in M. mohoity,P. dabryanus, and T. dalaicawere 117.1 mmol/L, 72.62 mmol/L, and 128.4 mmol/L and 88.83 mmol/L, 155.2 mmol/L, and 120.0 mmol/L, respectively, with safe concentrations of 18.77 mmol/L, 23.66 mmol/L, and 36.30 mmol/L respectively. The degree of carbonate-alkalinity tolerance was T. dalaica>P. dabryanus>M. mohoity. The joint effect of salinity and alkalinity was coordinated in M. mohoity and P. dabryanus, and the coordination coeffi-cients increased first and then decreased, but reached the maximum at 48 h. However, the combined effect was coordi-nated within 0-48 h in T. dalaica,whereas it was antagonized during 48–96 h, and the coefficient of antagonism in-creased gradually with exposure time. These results provide a theoretical basis for promoting breeding and culture of cobitid fish in high salinity-alkalinity water in the future.%以鳅科的黑龙江泥鳅(Misgurnus mohoity Dybowsky)、大鳞副泥鳅(Paramisgurnus dabryanus Sauvage)、达里湖高原鳅(Triplophysa dalaica)为实验材料,采用单因子静态急性毒性实验法和均匀正交设计法对其盐碱耐受能力进行研究.实验结果表明,黑龙江泥鳅、大鳞副泥鳅、达里湖高原鳅的24 h和96 h的氯化钠(NaCl)盐度半致死浓度(LC50)分别为15.64 g/L和13.58 g/L、15.43 g/L和14.18 g/L、14.00 g/L和11.57 g/L,安全浓度(SC)分别为4.12 g/L、4.03 g/L、3.74 g/L,盐度耐受能力顺序为:黑龙江泥鳅>大鳞副泥鳅>达里湖高原鳅.黑龙江泥鳅、大鳞副泥鳅、达里湖高原鳅的24 h和96 h碳酸氢钠(NaHCO3)碱度半致死浓度(LC50)分别为117.1 mmol/L和72.62 mmol/L、128.4 mmol/L和88.83 mmol/L、155.2 mmol/L和120.0 mmol/L,安全浓度分别为18.77 mmol/L、23.66 mmol/L、36.30 mmol/L,碱度耐受能力顺序为:达里湖高原鳅>大鳞副泥鳅>黑龙江泥鳅.盐碱交互作用对黑龙江泥鳅、大鳞副泥鳅均表现为协同作用,协同系数0~48 h依次增高,以后逐渐减小;而对达里湖高原鳅在0~48 h内表现为协同作用,在48~96 h时表现为拮抗作用,拮抗系数随着暴露时间的延长而增大.对比分析可知,3种鳅科鱼的盐碱耐受能力比大多数淡水鱼高,可作为盐碱水域的增养殖鱼类;而达里湖高原鳅在耐碱方面表现更突出,可以作为高碳酸盐型盐碱水的增养殖鱼类.
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