论文部分内容阅读
为了解中西太平洋人工集鱼装置下鲣鱼的稳定同位素特征,根据2013年2月至3月金枪鱼围网采集的鲣鱼样本,对其碳、氮稳定同位素组成(δ13C和δ15N)及碳氮比(C∶N)随叉长的分布进行了初步研究。结果显示,鲣鱼叉长范围为31.0~65.0 cm,平均值为(44.30±7.85)cm,优势叉长组为40.1~50.0 cm,占总体样本的45.12%。δ13C的平均值为(-15.94±0.59)‰,叉长对δ13C有显著性影响(F=10.92,P<0.05),各叉长组的δ13C均值相差较小,说明所有样本的初始饵料来源相似。δ15N的平均值为(17.50±1.81)‰,叉长对δ15N有显著性影响(F=16.72,P<0.05),且小型鲣鱼的δ15N明显大于大型同类,说明小型鲣鱼的营养位比大型同类高。C∶N的平均值为(3.06±0.05)‰,叉长对C∶N值均有显著性影响(F=4.21,P<0.05),各叉长组C∶N均值随叉长的增加而减小,说明鲣鱼的营养状况随叉长的增加而降低。
In order to understand the stable isotopic characteristics of anchovy in the artificial fish-collecting device of the Western and Central Pacific Ocean, the carbon and nitrogen stable isotope compositions (δ13C and δ15N) and the ratio of carbon to nitrogen were calculated based on the samples collected from tuna seine in February-March 2013, (C: N) with the distribution of the length of a preliminary study. The results showed that the length of the harpoon ranged from 31.0 to 65.0 cm with an average of (44.30 ± 7.85) cm, and the advantage of the long fork ranged from 40.1 to 50.0 cm, accounting for 45.12% of the overall sample. The mean value of δ13C was -15.94 ± 0.59 ‰, while the length of fork had a significant effect on δ13C (F = 10.92, P <0.05), and the difference of δ13C between each fork length group was small, indicating that all samples had similar sources of initial feed . The average value of δ15N was (17.50 ± 1.81) ‰, while the length of fork had a significant effect on δ15N (F = 16.72, P <0.05), and the δ15N of small-sized mackerel was significantly larger than that of large- Similar high. The average value of C: N was (3.06 ± 0.05) ‰, and the fork length had a significant effect on the C: N value (F = 4.21, P <0.05) Decrease, indicating that the nutritional status of anchovy decreased with the increase of fork length.