Mesozooplankton average mass during Mikhail Lomonosov cruise ML25, Part III

Mesozooplankton was sampled by open-closing JUDAY net with a 36 cm ring diameter and mesh size of 125 µm. 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 cm、网目尺寸125 µm的开闭式JUDAY网（open-closing JUDAY net）进行采样。该网具采用南森机械锁定系统（Nansen mechanical lock system）作为开闭机制，可将网具垂直拖曳通过预设标准水层（0-10 m、10-25 m、25-50 m、50-100 m、100-200 m、200-300 m、300-500 m），并在上层水层处完成封网。拖曳水深通过放出的钢缆长度以及钢缆倾斜角进行测算。采集得到的10~20 mL样品使用3%~4%的缓冲甲醛（buffered formaldehyde）进行固定，并在返回实验室后开展后续处理。所有桡足类（copepods）均被鉴定至属级分类阶元，其余分类学类群则分别鉴定至型、纲、目及科级分类阶元。