Mesozooplankton biomass during Mikhail Lomonosov cruise ML27, Part III

Mesozooplankton was sampled by open-closing JUDAY net with a 36 cm ring diameter and mesh size of 125 µm. Additionally, the JUDAY oceanic model JOM with 300 µm mesh size and 80 cm ring diameter was used. The open-closing mechanism used was the Nansen mechanical lock system allowing nets to be vertically towed through standard depths (0-10, 10-25, 25-50, 50-100, 100-200, 200-300, 300-500 m) and closed at the upper depth level. Depth of tow was evaluated by wire paid out and the angle of wire inclination. The 10-20 ml samples were preserved in 3-4% buffered formaldehyde and processed on return to the laboratory. All of copepods were identified to genus level, other taxanomic groups - to type, class, order and family levels.

中型浮游动物（Mesozooplankton）采用环径36厘米、网目尺寸125微米的开闭式JUDAY网进行采样。此外，本次研究还使用了网目尺寸300微米、环径80厘米的JUDAY海洋模式JOM（JUDAY oceanic model JOM）。该采样网采用的开闭机构为南森机械锁定系统（Nansen mechanical lock system），可使网具沿垂直方向在标准预设水层（0~10米、10~25米、25~50米、50~100米、100~200米、200~300米、300~500米）间拖曳，并在该水层的上层边界处关闭。拖曳水深通过放出的缆绳长度及缆绳倾角进行测算。采集得到的10~20毫升样品经3%~4%缓冲甲醛溶液固定，于返回实验室后开展后续处理工作。所有桡足类（copepods）均被鉴定至属级阶元，其余分类类群则分别鉴定至型、纲、目及科级阶元。