摘要
Winter ice cover of the Arctic Ocean makes year-round zooplankton sampling by plankton net a difficult task. Therefore, the collection of copepods with a sediment trap can be a powerful tool. In the present study, we analysed the seasonal changes in the population structures of five dominant planktonic copepods (Oncaea parila, Calanus hyperboreus, Metridia longa, Paraeuchaeta glacialis and Heterorhabdus norvegicus), which were collected using a sediment trap rotated at 10–15 day intervals moored at 184–260 m in the Northwind Abyssal Plain (75°00′N, 162°00′W) of the western Arctic Ocean from October 2010 to September 2012. Oncaea parila C6F with egg sacs occurred throughout the year, and the total abundance and composition of early copepodid stages (C1−C3) had two peaks each year. Calanus hyperboreus was dominated by C6F throughout the year, and their maturation was observed during February to May. Metridia longa C6F had a clear seasonality in lipid accumulation and gonad maturation: high lipid accumulation was observed from October to February, whereas gonad maturation occurred from March to September. Paraeuchaeta glacialis C6F also showed seasonality in lipid accumulation and gonad maturation, although their seasonal patterns varied from those of M. longa: high lipid individuals were abundant from February to April and mature individuals dominated from October to November. Heterorhabdus norvegicus showed seasonal changes in population structure as well: C1, C5, and C6M dominated from April to May, November to February and August to October, respectively. The life cycle patterns of these species are compared with those reported from other areas. While the results obtained by a sediment trap are inevitably subject to collection bias (i.e. passive collection at a fixed depth), a sediment trap should be considered as a powerful tool for the evaluation of the life cycle of planktonic copepods, especially in ice-covered oceans.
摘要译文
北冰洋的冬季冰雪覆盖，使全年的浮游动物采样由浮游生物网一项艰巨的任务。因此，桡足类有沉淀物捕集器的收藏可以是一个强大的工具。在本研究中，我们分析了季节变化的五个主要的浮游桡足类（Oncaea parila，中华哲hyperboreus，Metridia姜黄，Paraeuchaeta冰川和Heterorhabdus家鼠），这是用沉淀物收集器收集的人口结构，转速为10〜15天的间隔在Northwind深海平原停泊在184-260米（75°00N，162°00）北冰洋西部，从2010年10月2012年9月Oncaea parila C6F与卵囊发生一年四季，总每年丰度和早期copepodid阶段（C1-C3）的组合物有两个峰。中华哲hyperboreus主要是由C6F全年和2月期间，观察到五月的成熟。Metridia姜黄C6F有脂质的积累和性腺成熟一个明确的季节性：高脂质蓄积于10月观察到二月，而性腺成熟三月发生至九月。Paraeuchaeta冰川C6F也表现出季节性的脂质积累和性腺的成熟，虽然它们的季节性模式不同于M.龙格的变化：高血脂的个体较丰富，从二月到四月和十月支配至十一月成熟个体。Heterorhabdus家鼠呈季节性变化的人口结构，以及：C1，C5和C6M四月支配至五月，十一月到二月和八月到十月，分别。在这些物种的生命周期模式与来自其他区域报告相比较。虽然是由沉淀物捕集器中获得的结果不可避免地要受到收集偏压（即被动收集在一个固定的深度），沉淀物捕集器应被认为是一个强有力的工具浮游桡足类的生命周期的评价，特别是在冰覆盖海洋。
Kohei Matsuno[a][*]; Atsushi Yamaguchi[b]; Amane Fujiwara[a]; Jonaotaro Onodera[c]; Eiji Watanabe[c]; Naomi Harada[c] ; Takashi Kikuchi[c]. Seasonal changes in the population structure of dominant planktonic copepods collected using a sediment trap moored in the western Arctic Ocean[J]. Journal of Natural History, 2015,49(45-48): 2711-2726