【摘要】 基于2011年5月至2012年4月(12月和翌年1—2月冰期除外)在渤海莱州湾逐月网采的数据资料,进行了莱州湾浮游桡足类胸刺水蚤(Centropages)种类组成、生态分布和生产力估算的研究。结果显示:莱州湾最为常见的胸刺水蚤是腹胸刺水蚤(Centropages abdominalis)和背针胸刺水蚤(C.dorsispinatus)。腹胸刺水蚤主要出现在冬、春季,该种5月丰度最高,月均丰度为435ind./m~3;背针胸刺水蚤主要出现夏、秋季(7—11月),该种9月丰度最高,月均丰度(76ind./m~3)明显低于腹胸刺水蚤相应值。成体中,两种胸刺水蚤的雌/雄比介于1—2。水温较高时,两种胸刺水蚤的桡足幼体和成体的前体长较小。腹胸刺水蚤密集区(>100ind./m~3)主要分布于莱州湾湾口外东北侧,该水域水温多低于20°C;而背针胸刺水蚤密集区主要分布于水温介于21—25°C的湾内西侧近岸水域。粗略估算得到腹胸刺水蚤和背针胸刺水蚤桡足幼体和成体的月均生物量值分别为471μg C/m~3和50μg C/m~3,日生产力分别为89μg C/(m~3·d)和15μg C/(m~3·d)。两种胸刺水蚤具有明显季节更替和丰度空间分布互补性。背针胸刺水蚤已取代了2000年以前的优势种瘦尾胸刺水蚤(C.tenuiremis),成为莱州湾夏、秋季主要的胸刺水蚤。更多还原

【Abstract】 The copepod species of genus Centropages distribute widely in the shelf area of the world oceans, and they are very common in coastal marine ecosystem of Chinese marginal seas. To explore the species composition and seasonal abundance of Centropages in Laizhou Bay, Bohai Sea, nine monthly surveys were carried out from May 2011 to April 2012(excluding December 2011 and January and February 2012, because of the presence of sea ice). The copepodites of Centropages were sampled with plankton net of 160 μm mesh size. The results show Centropages abdominalis and C. dorsispinatus are the only two common species of genus Centropages in Laizhou Bay, showing seasonal succession and preference on geographical distributions. During all survey periods, C. abdominalis occurred mainly in winter and spring from November to June, with the highest abundance in May. By replacing C. tenuiremis in the last century, C. dorsispinatus had become the only dominant species of Centrapages in summer and autumn from June to November, and reached peak abundance in September. The monthly mean abundance of C. dorsispinatus(435ind/m~3) was much higher than that of C. abdominalis(76ind/m~3). In the adults of both Centropages species, the relative compositions of female and male varied irregularly with season, and the ratio of female to male ranged was 1—2. The prosome length of the two species changed seasonally, but was often shorter in warmer months. C. abdominalis was abundant offshore and became less abundant southwestward from the mouth to the bottom of the bay. Its density(>100ind/m~3) occurs near the mouth outside the bay with surface water temperature lower than 20°C. Contrarily, C. dorsispinatus concentrated mostly in the western part of the bay in water temperature 21—25°C. By calculation with empirical equations, the monthly mean values of copepods biomass and the daily production were estimated being, respectively, 471μg C/m~3 and 89μg C/(m~3·d) for C. abdominalis, and 50μg C/m~3 and 15μg C/(m~3·d) for C. dorsispinatus during the survey periods.更多还原