Vertical variations in physical and chemical conditions drive changes in marine zooplankton community composition. In turn, zooplankton communities play a critical role in regulating the transfer of organic matter produced in the surface ocean to deeper layers. Yet, the links between zooplankton community composition and the strength of vertical fluxes of particles remain elusive, especially on a global scale. Here, we provide a comprehensive analysis of variations in zooplankton community composition and vertical particle flux in the upper kilometer of the global ocean. Zooplankton samples were collected across five depth layers and vertical particle fluxes were assessed using continuous profiles of the Underwater Vision Profiler (UVP5) at 57 stations covering seven ocean basins. Zooplankton samples were analysed using a Zooscan and individual organisms were classified into 19 groups for the quantitative analyses. Zooplankton abundance, biomass and vertical particle flux decreased from the surface to 1000 m depth at all latitudes. The zooplankton abundance decrease rate was stronger at sites characterised by oxygen minima (<5µmol O₂.kg⁻¹) where most zooplankton groups showed a marked decline in abundance, except the jellyfishes, molluscs, annelids, large protists and a few copepod families. The attenuation rate of vertical particle fluxes was weaker at such oxygen-depleted sites. Canonical redundancy analyses showed that the epipelagic zooplankton community composition depended on the temperature, on the phytoplankton size distribution and the surface large particulate organic matter while oxygen was an additional important factor for structuring zooplankton in the mesopelagic. Our results further suggest that future changes in surface phytoplankton size and taxa composition and mesopelagic oxygen loss might lead to profound shift in zooplankton abundance and community structure in both the euphotic and mesopelagic ocean. These changes may affect the vertical export and hereby the strength of the biological carbon pump.

物理和化学条件的垂直变化驱动海洋浮游动物群落组成的变化。反过来，浮游动物群落在调节表层海洋产生的有机物质向更深层的转移方面发挥着关键作用。然而，浮游动物群落组成与粒子垂直通量强度之间的联系仍然难以捉摸，尤其是在全球范围内。在这里，我们提供了对全球海洋上部千米浮游动物群落组成和垂直粒子通量变化的综合分析。在五个深度层收集浮游动物样本，并在覆盖七个海洋盆地的 57 个站点使用水下视觉剖面仪 (UVP5) 的连续剖面评估垂直粒子通量。使用 Zooscan 分析浮游动物样本，并将个体生物分为 19 组进行定量分析。浮游动物丰度、生物量和垂直粒子通量在所有纬度从地表到 1000 m 深度都下降。浮游动物丰度下降率在氧极小（<5μmol O₂ .kg ^-1)，除了水母、软体动物、环节动物、大型原生生物和少数桡足类家族外，大多数浮游动物群的丰度都显着下降。在这种缺氧地点，垂直粒子通量的衰减率较弱。典型冗余分析表明，上层浮游动物群落组成取决于温度、浮游植物大小分布和表面大颗粒有机物，而氧气是中层浮游动物结构的另一个重要因素。我们的研究结果进一步表明，未来表面浮游植物大小和分类群组成以及中层氧损失的变化可能会导致富光和中层海洋中浮游动物丰度和群落结构的深刻变化。