Berge Jørgen, Cottier Finlo, Last Kim S, Varpe Øystein, Leu Eva, Søreide Janne, Eiane Ketil, Falk-Petersen Stig, Willis Kate, Nygård Henrik, Vogedes Daniel, Griffiths Colin, Johnsen Geir, Lorentzen Dag, Brierley Andrew S
University Centre in Svalbard, Pb 156, 9171 Longyearbyen, Norway.
Biol Lett. 2009 Feb 23;5(1):69-72. doi: 10.1098/rsbl.2008.0484.
High-latitude environments show extreme seasonal variation in physical and biological variables. The classic paradigm of Arctic marine ecosystems holds that most biological processes slow down or cease during the polar night. One key process that is generally assumed to cease during winter is diel vertical migration (DVM) of zooplankton. DVM constitutes the largest synchronized movement of biomass on the planet, and is of paramount importance for marine ecosystem function and carbon cycling. Here we present acoustic data that demonstrate a synchronized DVM behaviour of zooplankton that continues throughout the Arctic winter, in both open and ice-covered waters. We argue that even during the polar night, DVM is regulated by diel variations in solar and lunar illumination, which are at intensities far below the threshold of human perception. We also demonstrate that winter DVM is stronger in open waters compared with ice-covered waters. This suggests that the biologically mediated vertical flux of carbon will increase if there is a continued retreat of the Arctic winter sea ice cover.
高纬度环境在物理和生物变量方面呈现出极端的季节性变化。北极海洋生态系统的经典范式认为，在极夜期间，大多数生物过程会减缓或停止。一般认为在冬季停止的一个关键过程是浮游动物的昼夜垂直迁移（DVM）。DVM是地球上最大规模的生物量同步移动，对海洋生态系统功能和碳循环至关重要。在此，我们展示了声学数据，这些数据表明浮游动物的同步DVM行为在整个北极冬季的开阔水域和冰封水域中都持续存在。我们认为，即使在极夜期间，DVM也受太阳和月球光照的昼夜变化调节，而这些光照强度远低于人类感知阈值。我们还证明，与冰封水域相比，开阔水域的冬季DVM更强。这表明，如果北极冬季海冰覆盖持续退缩，由生物介导的碳垂直通量将会增加。
