四川裂腹鱼耳石碳、氧稳定同位素特征

为探讨耳石碳(δ¹³C)、氧(δ¹⁸O)稳定同位素在淡水鱼类群体识别中的作用,本研究以养殖条件下不同年龄组四川裂腹鱼为对象,采用稳定同位素质谱仪进行碳、氧同位素测定,揭示耳石中碳、氧稳定同位素特征,探讨其与环境间的关系. 结果表明:1⁺龄四川裂腹鱼δ¹³C和δ¹⁸O值均与耳石质量无显著相关关系,但在微耳石和星耳石之间存在显著差异;不同年龄四川裂腹鱼微耳石δ¹³C和δ¹⁸O平均值分别为(-9.58±0.06)‰、(-8.33±0.17)‰,其在雌雄个体之间均无显著性差异,但在不同年龄组间存在显著差异. 耳石δ¹⁸O和δ¹³C的关联分析能有效区分四川裂腹鱼不同养殖年龄群体,可作为一种识别淡水鱼类养殖群体的手段.

Otolith carbon and oxygen stable isotopes in laboratory-reared Schizothorax kozlovi

In order to investigate the role of otolith carbon (δ¹³C) and oxygen (δ¹⁸O) stable isotopes in identification of freshwater fish stocks, otolith δ¹³C and δ¹⁸O of cultured Schizothorax kozlovi at different ages were measured by stable isotope mass spectrometer. The relationships between otolith δ¹³C / δ¹⁸O and environment were discussed. The results showed that δ¹³C and δ¹⁸O values of S. kozlovi at age 1⁺ were not significantly correlated with otolith mass, but both were significantly different between lapillus and asteriscus. The average lapillus δ¹³C and δ¹⁸O values of S. kozlovi at different ages were (-9.58±0.06)‰ and (-8.33±0.17)‰, respectively. There was no significant difference of lapillus δ¹³C and δ¹⁸O between the sexes, but with significant difference among diffe-rent ages. The correlation of δ¹³C with δ¹⁸O was an effective method in identification of different culture stocks of S. kozlovi, which indicated the isotopic signatures of otolith could be used as a method to identify freshwater fish stocks.