人工鱼礁区三种习见肉食性软体动物营养生态位研究

以小黑山岛人工鱼礁区为研究区，利用稳定同位素技术分析该海域三种习见肉食性软体动物长蛸（Octopus minor）、短蛸（Octopus fangsiao）和脉红螺（Papana venosa）的营养生态位，进而判断物种种间关系。分析结果显示：食物来源范围由大到小依次为长蛸、脉红螺、短蛸，其中长蛸食物来源包含短蛸食物来源范围，但脉红螺与两种蛸类食物来源无交叉；营养级由高到低依次为长蛸、短蛸、脉红螺。长蛸与短蛸营养生态位重叠比例较高，存在明显的竞争关系，与短蛸相比，长蛸营养级更高，食物来源范围更广，在竞争中处于优势地位；脉红螺的营养生态位与两种蛸类无重叠，其营养级比两种蛸类更低且无捕食或竞争关系。

Trophic niche of three common carnivorous mollusca in artificial reef area

The trophic ecological niches of Octopus minor, Octopus fangsiao and Papana venosa, which are common carnivorous molluscs in the artificial reefs area of Xiaoheishan Island, Bohai Bay, China, were analyzed by stable isotope, and the trophic relationships between these species were discussed as well. The food diversities range from high to low, by O. minor, P. venosa and O. fangsiao. The food sources of O. minor include O. fangsiao, but there was no overlap of food sources between P. venosa and the two species of Octopus. O. minor showed the highest trophic level, followed by O. fangsiao and P. venosa from high to low. O. minor and O. fangsiao had high trophic niche overlap and showed significant trophic competitive relationship. Compared with O. fangsiao, O. minor presented higher trophic level and a wider range of food sources, and showed a dominant position in the trophic competition. The trophic niche of P. venosa did not overlap with the two species of Octopus, and its trophic level was lower than the two species of Octopus. There was no predation or trophic competition relationship between both Octopus and P. venosa.