Ryabov Alexey B, de Roos André M, Meyer Bettina, Kawaguchi So, Blasius Bernd
Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Oldenburg, Germany.
Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, The Netherlands.
Nat Ecol Evol. 2017 Jul;1(7):0177. doi: 10.1038/s41559-017-0177. Epub 2017 Jun 5.
Antarctic krill () - one of the most abundant animal species on Earth - exhibits a 5-6 year population cycle, with oscillations in biomass exceeding one order of magnitude. Previous studies have postulated that the krill cycle is induced by periodic climatological factors, but these postulated drivers neither show consistent agreement, nor are they supported by quantitative models. Here, using data analysis complemented with modeling of krill ontogeny and population dynamics, we identify intraspecific competition for food as the main driver of the krill cycle, while external climatological factors possibly modulate its phase and synchronization over large scales. Our model indicates that the cycle amplitude increases with reduction of krill loss rates. Thus, a decline of apex predators is likely to increase the oscillation amplitude, potentially destabilizing the marine food web with drastic consequences for the entire Antarctic ecosystem.
南极磷虾（）是地球上数量最为丰富的动物物种之一，呈现出5至6年的种群周期，生物量波动超过一个数量级。以往的研究推测，磷虾周期是由周期性气候因素引发的，但这些假定的驱动因素既未表现出一致的共识，也未得到定量模型的支持。在此，通过数据分析并辅以磷虾个体发育和种群动态建模，我们确定食物的种内竞争是磷虾周期的主要驱动因素，而外部气候因素可能在大尺度上调节其相位和同步性。我们的模型表明，周期振幅会随着磷虾损失率的降低而增加。因此，顶级捕食者数量的减少可能会增加振荡幅度，有可能破坏海洋食物网，给整个南极生态系统带来严重后果。
