| 摘要: |
| 碳、氮稳定同位素为分析淡水和海洋生态系统的生物营养关系提供了有力手段, 但在大洋鱼类中的应用还很少。本研究以热带东太平洋大青鲨(Prionace glauca)整节脊椎骨作为样品(叉长范围153-242cm), 运用稳定同位素技术, 分析大青鲨的δ13C值和δ15N值及其变化, 比较不同基线生物的选择对营养级计算的影响。结果表明, 大青鲨δ13C范围为-15.76‰- -13.41‰, 最大差值2.35‰; δ15N范围为10.62‰-17.72‰, 最大差值7.1‰; δ13C值和δ15N值随个体长度的变化不明显(可能原因是样品鱼均为较大个体), 性别间的差异不显著, 但不同基线生物的选择对营养级计算值的影响较大。本文研究表明, 通过整节脊椎骨的稳定同位素测定来获得大青鲨的摄食特征信息是可行的。由于基线生物对营养级计算的影响问题难以在短期内解决, 今后可将相对营养级或营养级的变化作为重点, 研究人类活动(如捕捞)对大洋鱼类摄食和营养级的影响。 |
| 关键词: 稳定同位素 营养级 大青鲨 东太平洋 |
| DOI：10.11693/hyhz20150900234 |
| 分类号: |
| 基金项目:国家自然科学基金项目, 41106118号。 |
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| TROPHIC POSITION FOR PRIONACE GLAUCA IN THE EASTERN PACIFIC OCEAN BASED ON STABLE ISOTOPE |
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WANG Jie1, ZHU Jiang-Feng1,2, DAI Xiao-Jie1,2, XIAO Yue-Yue1
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1.College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China;2.Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources, Ministry of Education, Shanghai Ocean University, Shanghai 201306, China
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| Abstract: |
| Stable isotope techniques provide a powerful tool for the analysis of trophic relations in freshwater and marine ecosystems. However, relatively fewer studies have been focused on oceanic fishes. In this study, using whole section of vertebrae of blue shark (Prionace glauca) from the eastern Pacific Ocean (153-242cm fork length), stable isotope ratios of carbon and nitrogen (δ13C and δ15N), and trophic position (TP) of blue shark were analyzed. The results show that the ranges of δ13C and δ15N were -15.76‰- -13.41‰ and 10.62‰-17.72‰, respectively. There was no obvious trend in the relationship between δ13C or δ15N and blue shark size; and no significant difference in δ13C or δ15N between sexes. However, the choice of different baseline species affected obviously the values of TP. Therefore, it is feasible to investigate blue shark feeding ecology based on stable isotope analysis with the whole section of vertebrae. We suggest that future studies shall focus on the relative changes of TP, to reduce the impact from the selection of baseline species. |
| Key words: stable isotope trophic position Prionace glauca eastern Pacific Ocean |
