秋季黄海中华哲水蚤(Calanus sinicus)脂肪酸组成及其指示作用

采用气相色谱法对秋季黄海颗粒悬浮物和中华哲水蚤的脂肪酸组成及其指示作用进行了研究。结果表明,黄海表层海水中硅藻所占比例要大于甲藻。硅藻在黄海南部浮游植物中所占比重高于黄海北部,甲藻在黄海南北部的差别不大。从脂肪酸组成来看,中华哲水蚤雌体、雄体和桡足幼体都摄食硅藻和甲藻,雌体和雄体摄食的硅藻远多于甲藻,而桡足幼体摄食的甲藻则比雌体和雄体多。雄体和桡足幼体植食性的程度高于雌体,而雌体则可能由于繁殖活动的需要,还摄食了原生动物等其它一些营养丰富的食物。对冷水团内外中华哲水蚤脂肪酸组成研究发现,桡足幼体比雌体积累了更多的脂肪酸以满足度夏过程中的能量需求和后期繁殖的需要。

FATTY ACID COMPOSITION OF CALANUS SINICUSIN AUTUMN IN YELLOW SEA AND ITS IMPLICATIONS

The fatty acid composition in seston and Calanus sinicus were studied in autumn in Yellow Sea. The results showed that diatoms occupied a larger part in phytoplankton in the surface layer in Yellow Sea. Compared to the northern part, diatoms were more concentrated in the southern Yellow Sea. Diatom accounted for a major part in the diet of C. sinicus according to the fatty acid compositions. Copepodite showed a preferential feeding on dinoflagellates compared to female and male. With 20:1 + 22:1 as a herbivorous marker, female seemed to be less herbivorous than male and cope-podite. We inferred that female may have a wider range of food particles including some animal baits such as protozoan and other organic detritus which is more nutritious. The fatty acid compositions of C. sinicus in and out of Yellow Sea Cold Bottom Water (YSCBW) were analyzed. The content of fatty acid in copepodite was significantly higher than in female. The large bodies of fatty acid might be the most important energy source for copepodite in oversummering and may also benefit the development from copepodite to adult along with the recession of YSCBW.