东海渔山列岛浅海岩礁区大型消费者食源及营养级分析

FOOD SOURCE AND TROPHIC LEVEL OF LARGE CONSUMERS IN ROCKY COASTAL WATERS OFF YUSHAN ISLANDS IN THE EAST CHINA SEA

采用碳氮稳定性同位素技术分析了东海渔山列岛浅海岩礁区生物的碳氮稳定性同位素比值,研究了浅海岩礁区14种初级生产者、61种消费者的营养级。结果表明,东海渔山列岛浅海岩礁区消费者的营养级(TL)变化范围为2.000—4.760,推断东海渔山列岛浅海岩礁区生物有4个营养级;初级生产者δ^(15)N值变化范围为2.75‰—6.85‰,消费者δ^(15)N值变化范围为4.57‰—13.39‰;通过对不同生物δ^(15)N值的比较发现,各类别生物间的δ^(15)N值差异高度显著(P<0.01),短滨螺(Littorina brevicula)的δ^(15)N值最低(4.57‰),中国花鲈(Lateolabrax maculatum)和黑鲷(Acanthopagrus schlegelii)的δ^(15)N值最大,分别为11.87‰和13.39‰;单因素方差分析(One-Way ANOVA)表明4类食源间δ^(15)N和δ^(13)C值差异高度显著(P<0.01);食源分析表明,鱼类的贡献范围(0.00%—7.09%)最小,初级生产者的贡献范围(27.05%—57.99%)最大;比较发现不同海域同一种生物体内富集的15N量也存在差异,这也从一个侧面反映出不同海域间生物的群落结构和稳定性存在差异。

To understand the food source and trophic level of large consumers in rocky coastal waters off Yushan Islands, the East China Sea, Zhejiang, we analyzed the stable carbon and nitrogen isotope ratio in local rocky organisms using stable isotope technique. Fourteen primary producers and 61 consumers were selected. The results showed that the trophic level ranged 2.000—4.760, of which four trophic levels could be recognized. The variation range of δ^（15）N value for primary producers was 2.75‰—6.85‰, and consumers 4.57‰—13.39‰. The δ^（15）N values of different organisms varied significantly（P0.01）, from 4.57‰ in Littorina brevicula to 11.87‰ in Lateolabrax maculatum and 13.39‰ in black porgy Acanthopagrus schlegelii. The food sources in the region could be divided into four groups. The range of fish contribution was the smallest（0.00%—7.09%）, and that of primary producers was the largest（27.05%—57.99%）. In addition, ^（15）N enrichment in the same species in different sea areas varied, reflecting differences in structure and stability of local communities among the parts of the study area.